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Objective HLA-DRB1 alleles, particularly the shared epitope (SE) alleles, are strongly associated with RA. Different genetic structures underlie the production of the various autoantibodies in RA. While extensive genetic analyses have been conducted to generate a detailed profile of ACPA, a representative autoantibody in RA, the genetic architecture underlying subfractions of RF other than IgM-RF , namely IgG-RF , known to be associated with rheumatoid vasculitis, is not well understood. Methods We enrolled a total of 743 RA subjects whose detailed autoantibody (IgG-RF, IgM-RF, and ACPA) data were available. We evaluated co-presence and correlations of the levels of these autoantibodies. We analysed associations between the presence or levels of the autoantibodies and HLA-DRB1 alleles for the 743 RA patients and 2008 healthy controls. Results We found both IgG-RF(+) and IgG-RF(–) RA subjects showed comparable associations with SE alleles, which was not observed for the other autoantibodies. Furthermore, there was a clear difference in SE allele associations between IgG-RF(+) and (–) subsets: the association with the IgG-RF(+) subsets was solely driven by HLA-DRB1*04:05 , the most frequent SE allele in the Japanese population, while not only HLA-DRB1*04:05 but also HLA-DRB1*04:01 , less frequent in the Japanese population but the most frequent SE allele in Europeans, were main drivers of the association in the IgG-RF(–) subset. We confirmed that these associations were irrespective of ACPA presence. Conclusion We found a unique genetic architecture for IgG-RF(–) RA, which showed a strong association with a SE allele not frequent in the Japanese population but the most frequent SE allele in Europeans. The findings could shed light on uncovered RA pathology. [ABSTRACT FROM AUTHOR]

Objective To evaluate the effect of sodium dodecyl sulfate (SDS) and 2-mercaptoethanol (2-ME) on antigen-antibody binding when incubated at 100°C, which is the pretreatment temperature required for western blots. Methods Serum that tested positive for hepatitis B surface antigen (HBsAg) plus loading buffer were mixed at a ratio of 4:1 and incubated in a water bath. We then detected HBsAg using double immunodiffusion and ELISA. Results The HBsAg titer was 1:512 in the control group when incubated at 37°C. Incubation with SDS at 100°C reduced the antigen titer to 1:32. The inhibitory effect on HBsAg titer reached 96.9% after incubation at 100°C with SDS and 2-ME. Conclusion We detected strong inhibition of antigens in western blots via SDS and 2-ME. It is likely that false-negative results will be obtained from western blots of antigens with weak resistance to these reagents. [ABSTRACT FROM AUTHOR]

Objective To find suitable biomarkers for diagnosis of Breast cancer in serum and saliva; also, to examine the correlation between salivary and serum concentrations of suitable biomarkers. Methods This case-control study included 30 women with breast cancer as a case group and 30 healthy women as a matched control group. Blood and saliva specimens were collected from all participants. We evaluated serum and salivary cancer antigen 15-3 (CA15-3), carcinoembryonic antigen (CEA), estradiol, vaspin, and obestatin concentrations. Mann-Whitney U testing and Spearman correlation coefficients were used for statistical analysis. Results Serum and salivary concentrations of estradiol were significantly higher in patients with breast cancer (BC) than in healthy women (P <.05). Also, serum CEA and salivary obestatin concentrations were significantly higher in BC patients than in the control group (P <.05). However, there was no significant difference between other parameters in patients with BC and controls. We observed a positive correlation between serum and salivary concentrations of CA15-3, as well as a negative correlation between serum and salivary concentrations of vaspin and obestatin. Conclusion The results of this study demonstrated that concentrations of CEA and estradiol in serum, obestatin in serum and saliva, and estradiol in saliva were significantly different between the 2 groups. [ABSTRACT FROM AUTHOR]

Study question: Are the immune cell profiles and the cytokine concentrations in follicular fluid (FF) and serum at the preovulatory stage different in conventional exogenous gonadotrophin stimulated IVF (c-IVF) compared with natural cycle IVF (NC-IVF)?Summary answer: The cell counts of CD45+ leucocytes and T cell subpopulations and the cytokine concentrations in FF and serum are different in c-IVF compared to NC-IVF.What is known already: FF-derived cells are heterogeneous. Immune cells are involved in intra-ovarian processes and cytokines are required for normal follicular development. Gonadotrophins stimulate the regulatory intrafollicular system and influence the local distribution of immune cells and the intrafollicular release of cytokines. Administration of exogenous gonadotrophins may have a significant effect on this local regulatory system, which then in turn could influence oocyte quality.Study design, size, duration: The study included 105 patients, 69 undergoing c-IVF and 36 undergoing NC-IVF. c-IVF was performed by exogenous ovarian stimulation with hMG and GnRH antagonists.Participants/materials, setting, methods: FF samples were collected from the first dominant follicle in c-IVF without pooling and from single leading preovulatory follicles in NC-IVF. Three different approaches were used to analyze FF samples: (i) microscopic investigation of CD45+ leucocytes, (ii) fluorescence-activated cell sorting to determine CD19+ B cells and CD3+ T cells including T cell subpopulations (CD4+, CD8+), and (iii) evaluation of tumour necrosis factor-alpha (TNF-α), interferon-gamma (INF-γ), interleukins (IL)-2, -6, -8, -10 and vascular endothelial growth factor (VEGF) levels in matched FF and serum samples using the Bio-Plex® platform.Main results and the role of chance: FF obtained from c-IVF contained proportionally more CD45+ leucocytes (P = 0.0384), but fewer CD8+ cytotoxic T cells than FF from NC-IVF. CD3+ T lymphocytes were the most common type of lymphocytes, and the number thereof was comparable in the two study groups. In c-IVF, serum VEGF levels were higher (P = 0.007) than in NC-IVF while FF contained marginally decreased concentrations of IL-8 in c-IVF in comparison to NC-IVF. The cytokine concentration gradient between FF and serum in c-IVF was 10-fold for IL-8 and 8-fold for VEGF and thereby markedly lower than in NC-IVF, where the differences were 32-fold and 30-fold, respectively. Strong positive correlations were determined between FF- IL-10 and FF- VEGF in c-IVF (r = 0.85, P < 0.0001) and in NC-IVF (r = 0.81, P < 0.0001).Large scale data: N/A.Limitations, reasons for caution: The ovulation of NC-IVF follicles was induced by the exogenous administration of hCG, which means that the environment did not fully correspond to the physiological situation.Wider implications of the findings: The differences in the immune profile and the cytokine concentrations in c-IVF and NC-IVF follicles support the hypothesis that conventional ovarian stimulation affects indirectly and heterogeneously the intrafollicular milieu, and thereby possibly affects the oocyte quality and the IVF outcome. However, further studies are needed to confirm our findings and to refine stimulation protocols in the context of optimizing the intrafollicular environment during oocyte maturation.Study funding/competing interest(s): The study was supported by a research grant from IBSA Institut Biochimique SA and MSD Merck Sharp & Dohme GmbH. The authors are clinically involved in low dose mono-follicular stimulation and IVF-therapies, using gonadotrophins from all gonadotrophins distributors on the Swiss market, including Institut Biochimique SA and MSD Merck Sharp & Dohme GmbH. [ABSTRACT FROM AUTHOR]

Study question: Do cell adhesion molecules play a role in endometriosis, and can they be used as a biomarker for diagnosing endometriosis?Summary answer: Altered expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) in the endometrium and peritoneum may play a key role in endometriosis and the soluble VCAM-1/soluble ICAM-1 ratio is a promising biomarker.What is known already: Cell adhesion molecules are cell surface proteins that mediate cellular adherence, inflammatory and immune responses, and cancer-related biological processes. Altered expression of VCAM-1 and ICAM-1 in women with endometriosis has been investigated previously; however, gene expression levels in tissues and protein levels in the serum have not been investigated in the same patients.Study design size, duration: We performed a prospective, longitudinal study (the Endometriosis Marker Austria) in patients who underwent a laparoscopy for benign gynecological pathology in a university-based tertiary referral center for endometriosis. From a total of 138 women who were included in the study from July 2013 through September 2014, 97 had not received hormonal treatment for at least 3 months prior to recruitment and were included in the analysis; 49 (50.5%) of these women had endometriosis, and the 48 (49.5%) who did not have endometriosis served as a control group.Participants/materials setting methods: During laparoscopy, tissue samples were obtained from ectopic and eutopic endometrium, and from normal pelvic peritoneum. In addition, serum samples were collected immediately before and 6-10 weeks after surgery. The mRNA levels of VCAM-1, ICAM-1 and epithelial cell adhesion molecule (EpCAM) were measured using quantitative real-time PCR, and serum protein levels of soluble VCAM-1 (sVCAM-1), ICAM-1 (sICAM-1) and EpCAM (sEpCAM) were measured using ELISA and correlated with endometriosis status.Main results and the role of chance: The mRNA levels of both VCAM-1 and ICAM-1 were higher in ectopic endometriotic lesions than in eutopic endometrium (P < 0.001). Moreover, the mRNA levels of both VCAM-1 and ICAM-1 were higher in normal peritoneum samples obtained from women with endometriosis compared to those from controls (P = 0.038 and P = 0.009). The mRNA levels of VCAM-1 were also higher in the eutopic endometrium samples obtained from women with endometriosis compared to controls (P = 0.018). With respect to serum protein levels, compared to controls, the women with endometriosis had lower serum levels of sICAM-1 (P = 0.042) and higher levels of sVCAM-1 (P < 0.001). Our analysis revealed that the serum levels of sVCAM-1 were not affected by lesion entity, menstrual cycle phase or disease severity. An receiver operating characteristics curve, calculated to determine whether preoperative serum sVCAM-1 concentration can be used to predict endometriosis, found an AUC of 0.868 with 80% specificity and 84% sensitivity at a cutoff value of 370 pg/ml. This predictive performance can be further improved by calculation of the sVCAM-1/sICAM-1 ratio, leading to an AUC of 0.929 with 86.7% specificity and 90.3% sensitivity at a cutoff ratio value of 1.55.Large scale data: Not applicable.Limitations reasons for caution: The relatively small sample size in the expression analyses is a possible limitation of this study.Wider implications of the findings: Our findings could contribute to an improved understanding of the pathogenesis of endometriosis and the role of cell adhesion molecules. In addition, the results may lead to the development of new, non-invasive tools for diagnosing endometriosis. The ability to diagnose patients by measuring serum sVCAM-1 levels or the sVCAM-1/sICAM-1 ratio would have considerable clinical value.Study funding/competing interest(s): The Ingrid Flick Foundation (Grant no. FA751C0801), which played no role in the study design, data collection and analysis, decision to publish or preparation of the manuscript. The authors declare no competing interests. [ABSTRACT FROM AUTHOR]

O-glycans are suitable targets as novel and useful tumor markers. The structures of O-glycans in human sera from four healthy controls were precisely analyzed to obtain the reference O-glycan database. O-glycans were prepared from sera by hydrazine treatment followed by fluorescent labeling with aminopyridine and identified using two-dimensional mapping, enzymatic digestion and mass spectrometry (MS) together with methanolysis and the use of newly synthesized sulfated oligosaccharides as standards. O-glycans, present at more than 0.01% of the total O-glycans, were analyzed, and 18 kinds of acidic and 2 kinds of neutral glycans were identified. NeuAcα2-3Galβ1-3N-acetylgalactosamine (GalNAc) (61–64%), NeuAcα2-3Galβ1-3(NeuAcα2-6)GalNAc (15–26%) and Galβ1-3GalNAc (6–14%) were major components while other sialylated glycans, Galβ1-3(NeuAcα2-6)GalNAc, Galβ1-4GlcNAcβ1-6(NeuAcα2-3Galβ1-3)GalNAc and NeuAcα2-3Galβ1-4GlcNAcβ1-6(NeuAcα2-3Galβ1-3)GalNAc were relatively minor components, accounting for ∼1–2%. Very minor glycans accounting for ∼0.01–0.1% of the total include (i) the neutral glycan, Galβ1-4GlcNAcβ1-6(Galβ1-3)GalNAc, (ii) sialylated glycans, having sialyl Tn antigen, agalacto and trisialylated structures, (iii) fucosylated glycans forming blood type H antigen, blood type A antigen, blood type B antigen, Lewis X antigen and sialyl Lewis X antigen and (iv) sulfated glycans, having 6-sulfo and 3′-sulfo structures. Two kinds of clinically applied tumor markers namely sialyl Tn antigen and sialyl Lewis X antigen in healthy controls sera were revealed to be present at ∼0.1–0.2% of the total. However, other markers such as CA19-9 and DU-PAN-2 were not found, suggesting the relative amounts of these glycans to be <0.01%. These detailed O-glycan profiles will help to find novel carbohydrate tumor markers. [ABSTRACT FROM AUTHOR]

There is increasing interest in biologics, i.e. human-originated biological pharmaceutics. Most of the protein drugs developed so far, such as immunoglobulins and erythropoietin, are secreted glycoproteins; as a result, any non-human-type glycans, such as αGal and NeuGc, derived from animal cells and sera must be removed to circumvent undesirable immunogenic reactions. In this study, we made an extensive search for potential xenoantigenic glycans among a panel of mammalian sera. As a result, sera belonging to the order Artiodactyla, i.e. bovine, lamb and goat sera, were found to contain substantial amounts of hypersialylated biantennary glycans closely associated with a type-I lactosamine structure containing a unique tetrasaccharide, Siaα2-3Galβ1-3(Siaα2-6)GlcNAc. In all three Artiodactyla sera, the most abundant structure was Siaα2-3Galβ1-3(Siaα2-6)GlcNAcβ1-2Manα1-3[Siaα2-6Galβ1-4GlcNAcβ1-2Manα1-6]Manβ1-4GlcNAcβ1-4GlcNAc. A dually hypersialylated biantennary structure, Siaα2-3Galβ1-3(Siaα2-6)GlcNAcβ1-2Manα1-3[Siaα2-3Galβ1-3(Siaα2-6)GlcNAcβ1-2Manα1-6]Manβ1-4GlcNAcβ1-4GlcNAc, was also abundant (10%) in bovine serum. The amount of hypersialylated glycans among total sialylated glycans was 46, 26 and 23% in bovine, lamb and goat sera, respectively. On the other hand, such structures could not be detected in the sera of other animals including human. The biological functions and the immunogenicity of the hypersialylated glycans in these animals remain to be elucidated; however, it is worth noting that glycoproteins biosynthesized from Artiodactyla cells and those contaminated with bovine serum might enhance undesirable antigenicity in human patients. [ABSTRACT FROM AUTHOR]

Background. Many deaths from cryptococcal meningitis (CM) may be preventable through early diagnosis and treatment. An inexpensive point-of-care (POC) assay for use with urine or a drop of blood would facilitate early diagnosis of cryptococcal infection in resource-limited settings. We compared cryptococcal antigen (CRAG) concentrations in plasma, serum, and urine from patients with CM, using an antigen-capture assay for glucuronoxylomannan (GXM) and a novel POC dipstick test. Methods. GXM concentrations were determined in paired serum, plasma, and urine from 62 patients with active or recent CM, using a quantitative sandwich enzyme-linked immunosorbent assay (ELISA). A dipstick lateralflow assay developed using the same monoclonal antibodies for the sandwich ELISA was tested in parallel. Correlation coefficients were calculated using Spearman rank test. Results. All patients had detectable GXM in serum, plasma, and urine using the quantitative ELISA. Comparison of paired serum and plasma showed identical results. There were strong correlations between GXM levels in serum/urine (rs = 0.86; P < .001) and plasma/urine (rs = 0.85; P < .001). Levels of GXM were 22-fold lower in urine than in serum/plasma. The dipstick test was positive in serum, plasma, and urine in 61 of 62 patients. Dipstick titers correlated strongly with ELISA. Correlations between the methods were 0.93 (P < .001) for serum, 0.94 (P < .001) for plasma, and 0.94 (P < .001) for urine. Conclusions. This novel dipstick test has the potential to markedly improve early diagnosis of CM in many settings, enabling testing of urine in patients presenting to health care facilities in which lumbar puncture, or even blood sampling, is not feasible. [ABSTRACT FROM AUTHOR]

Cutaneous anthrax outbreaks occurred in Bangladesh from August to October 2009. As part of the epidemiological response and to confirm anthrax diagnoses, serum samples were collected from suspected case patients with observed cutaneous lesions. Anthrax lethal factor (LF), anti-protective antigen (anti-PA) immunoglobulin G (IgG), and anthrax lethal toxin neutralization activity (TNA) levels were determined in acute and convalescent serum of 26 case patients with suspected cutaneous anthrax from the first and largest of these outbreaks. LF (0.005-1.264 ng/mL) was detected in acute serum from 18 of 26 individuals. Anti-PA IgG and TNA were detected in sera from the same 18 individuals and ranged from 10.0 to 679.5 μg/mL and 27 to 593 units, respectively. Seroconversion to serum anti-PA and TNA was found only in case patients with measurable toxemia. This is the first report of quantitative analysis of serum LF in cutaneous anthrax and the first to associate acute stage toxemia with subsequent antitoxin antibody responses. [ABSTRACT FROM AUTHOR]

BACKGROUND We explored the relevance of blood type to ovarian reserve, as reflected by early follicular phase FSH levels. METHODS For this cross-sectional observational study, early follicular phase serum levels of FSH (mIU/ml) and estradiol (E2, pg/ml), and information on blood type (A, B, AB and O) and patient age were procured for female patients, ≤45 years age (n= 544), who were undergoing fertility evaluation at one of two tertiary care facilities. Serum FSH > 10 mIU/ml was taken to reflect diminished ovarian reserve (DOR). Data distribution for FSH and age was analyzed and non-parametric tests used for comparisons across blood groups. Multivariable logistic regression analyses determined the relationship between elevated FSH and respective blood types after adjusting for age and study site. RESULTS Prevalence of blood types according to order of frequency was: O (45%), A (35%), B (16%) and AB (5%). After adjusting for age and study site, patients with blood type O were twice as likely to exhibit FSH > 10 mIU/ml compared with those with A or AB blood types [odds ratio (OR) 2.36; 95% confidence interval (CI) 1.27–4.41; P= 0.007], and three times as likely to manifest FSH > 12m IU/ml (OR 3.48, 95% CI 1.46–7.32, P= 0.004). The B blood group antigen failed to exhibit any relationship with ovarian reserve as reflected by baseline FSH (P> 0.05). CONCLUSIONS The A blood group antigen appears to be protective for ovarian reserve, whereas blood type O appears to be associated with DOR, in a relationship that is independent of advancing age. Further studies are needed to establish causality and identify the underlying mechanisms for the association. [ABSTRACT FROM AUTHOR]

Most adenocarcinomas express altered MUC1 as a tumour-associated antigen. Due to suboptimal glycosylation in tumour-associated MUC1, the apomucin core is exposed, revealing new epitopes for antibody-directed immunotherapy. The human PH1 Fab binds specifically to this MUC1 apomucin. We describe the engineering and functional characterization of bi- and trivalent recombinant antibody derivatives from the PH1 Fab. Biand tribodies were made using the disulfide-stabilized Fab fragment as a heterodimerization scaffold with PH1 single-chain variable fragments fused to either one or both Fab-chain C-termini. Immunoassays revealed 27-and 165-fold improved dissociation constants (KD = 30 and 5 nM) of the PH1 bi- and tribodies compared with the parental Fab (KD = 820 nM). Unexpectedly, major differences were seen in the ability of the antibody constructs to bind shed and tumour cell-tethered MUC1. While the tribody did not discriminate between both MUC1 forms, the bibody demonstrated preferential interaction with membrane-bound MUC1 compared with shed MUC1. This preferential recognition of membrane-bound MUC1, along with the high serum stability of the bibody, its intermediate size and efficient internalization by MUC1+ cells, makes the human PH1-derived bibody a valuable candidate as a cancer-targeting therapeutic. [ABSTRACT FROM AUTHOR]

Background. Cryptococcal meningitis (CM) remains a common AIDS-defining illness in Africa and Asia. Subclinical cryptococcal antigenemia is frequently unmasked with antiretroviral therapy (ART).We sought to define the cost-effectiveness of serum cryptococcal antigen (CRAG) screening to identify persons with subclinical cryptococcosis and the efficacy of preemptive fluconazole therapy. Methods. There were 609 ART-naive adults with AIDS who started ART in Kampala, Uganda, and who had a serum CRAG prospectively measured during 2004-2006. The number needed to test and treat with a positive CRAG was assessed for ⩾30-month outcomes. Results. In the overall cohort, 50 persons (8.2%) were serum CRAG positive when starting ART. Of 295 people with a CD4+ cell count ⩽100 cells/μL and without prior CM, 26 (8.8%; 95% confidence interval [CI], 5.8%- 12.6%) were CRAG positive, of whom 21 were promptly treated with fluconazole (200-400 mg) for 2-4 weeks. Clinical CM developed in 3 fluconazole-treated persons, and 30-month survival was 71% (95% CI, 48%-89%). In the 5 CRAG-positive persons with a CD4+ cell count ⩽100 cells/μL treated with ART but not fluconazole, all died within 2 months of ART initiation. The number needed to test and treat with CRAG screening and fluconazole to prevent 1 CM case is 11.3 (95% CI, 7.9-17.1) at costs of $190 (95% CI, $132-$287). The number needed to test and treat to save 1 life is 15.9 (95% CI, 11.1-24.0) at costs of $266 (95% CI, $185-$402). The cost per disability-adjusted life year saved is $21 (95% CI, $15-$32). Conclusions. Integrating CRAG screening into HIV care, specifically targeting people with severe immunosuppression (CD4+ cell count ⩽100 cells/μL) should be implemented in treatment programs in resource-limited settings. ART alone is insufficient treatment for CRAG-positive persons. [ABSTRACT FROM AUTHOR]

Background. The Th17 subset has been implicated in the pathogenesis of a number of autoimmune diseases. However, little is known about its role in anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitis (AAV). We measured serum levels of IL-17A and associated upstream cytokines and the frequency of IL-17-producing autoantigen-specific T cells in patients with AAV. [ABSTRACT FROM PUBLISHER]

Immunotherapy can be used to induce immunological tolerance by a number of different protocols. During the last decade the ability to use tolerogenic dendritic cells (DCs) to prevent autoimmunity has received much attention. Many studies have attempted to use immature or semi-mature DCs to induce tolerance in the non-obese diabetic (NOD) mouse model of human type 1 diabetes. However, most studies to date have used protocols in which generation of DCs involved a culture step in fetal bovine serum (FBS)-supplemented medium which may affect tolerance induction in a non-specific fashion. Indeed, several studies have shown that DCs cultured in the presence of FBS will induce a powerful T helper type 2 (Th2) immune response towards FBS-related antigens which can suppress an ongoing immune response. Hence, this may interfere with diabetes development in the NOD mouse by induction of immune deviation rather than by antigen-specific tolerance. In order to test whether antigen-specific tolerance induction by DC therapy is feasible in the NOD mouse, we therefore generated immature DCs using autologous serum [normal mouse serum (NMS)-supplemented cultures] instead of FBS, and we show that these DCs can protect NOD mice from diabetes, if pulsed with insulin-peptide antigens before adoptive transfer. Our data therefore support that DC therapy is able to prevent diabetes in the NOD mouse in an antigen-specific manner. [ABSTRACT FROM AUTHOR]

Objective. To investigate the role of HLA-G in AS. [ABSTRACT FROM PUBLISHER]

Background. Maternal antibodies contribute to the protection of neonates from infectious diseases during the first months of life. The seroprevalence of antibodies specific for polysaccharide or protein antigens from vaccinepreventable pathogens was determined in paired maternal delivery and cord blood serum samples. Methods. Antibody concentrations specific for Neisseria meningitidis serogroup C polysaccharide, Haemophilus influenzae type B polysaccharide, diphtheria toxin, tetanus toxin, and pertussis toxin, filamentous hemagglutinin, and pertactin from Bordetella pertussis were determined by enzyme-linked inmmunosorbent assay (ELISA), fluorescent multiplex immunoassay, or serum bactericidal assay. Results. We investigated 197 paired maternal delivery and cord blood samples. The mean maternal age was 30.8 years, and the mean gestational age was 39.3 weeks. Cord geometric mean concentrations (GMCs) were 0.23 mg/mL for N. meningitidis serogroup C and 0.53 mg/mL for H. influenzae type B. Cord GMCs to diphtheria and tetanus were 0.16 and 1.06 IU/mL, respectively, and cord GMCs to pertussis toxin, filamentous hemagglutinin, and pertactin were 16.2, 34.8, and 17.7 ELISA U/mL (by ELISA), respectively. Cord GMCs to polysaccharide were, in general, 107% identical to maternal GMCs, whereas cord GMCs to proteins were a mean of 157% of maternal concentrations. In addition, the levels of anti-N. meningitidis serogroup C immunoglobulin G1 and G2 in cord blood were 145% and 109% of maternal concentrations, respectively. Conclusions. Antibody concentrations directed toward polysaccharide were equal in maternal and cord blood, whereas antibody concentrations to proteins were 1.6 times higher in cord blood than in maternal blood. This is probably attributable to the less-active transportation of immunoglobulin G2 antibodies elicited by polysaccharide. Despite proper placental transfer, cord antibody concentrations are low, possibly placing neonates at risk before they receive their primary vaccinations. [ABSTRACT FROM AUTHOR]

Background. The frequency of protective antiviral memory B cells after hepatitis B virus (HBV) vaccination is unknown. Methods. A novel 2-step immunomagnetic protocol to assess the ex vivo frequency of protective HBV surface antigen (HBsAg)-specific memory B cells was used. Results. HBsAg-specific memory B cells were detected in vaccinated individuals, although at very low frequency (median, 0.2% of CD19+ cells [range, 0%-4% of CD19+ cells]). No correlation existed between the frequency of HBsAg-specific memory B cells and the corresponding serum antibody titer or B cell enzyme-linked immunosorbent spot findings. Conclusion. Our results indicate sustained B cell-mediated protection against HBV despite waning antibody titers, which is consistent with clinical observations. [ABSTRACT FROM AUTHOR]

Background. This study compared patterns of recognition of defined Schistosoma haematobium adult worm antigens by serum antibodies from schistosome-exposed Zimbabweans aged 5 -18 years. Methods. The population was stratified by age and infection intensity into 9 groups within which serum specimens were pooled and used to screen for protein recognition by 2-dimensional Western blotting. Recognized proteins were identified by electrospray ionizing tandem mass spectrometry. Results. A total of 71 antigens were recognized by ⩾1 of the serum pools. The recognition varied distinctly with host age and infection intensity, with some isoform-specific responses. The repertoire of antigens recognized increased with age, peaking in the oldest participants whose had no or mild-to-moderate infection intensity. The intensity of antigen recognition also increased with age, peaking in the oldest participants with the heaviest infection intensity. Conclusions. The recognition of specific schistosome antigens, both in terms of the diversity of antigens recognized and the intensity of antigen recognition, increased with duration of exposure to infection, supporting the hypothesis that the slow development of schistosome-acquired immunity is due to the slow accumulation of responsiveness to relevant parasite antigens. [ABSTRACT FROM AUTHOR]

Background. Echinococcus multilocularis growth and persistent granuloma, which lead to the development of the severe parasitic disease alveolar echinococcosis (AE), might be caused by abnormal expression of stress-induced proteins, with subsequent abnormalities in T cell activation. Similar to its involvement in tumors, the NKG2D-major histocompatability complex class I chain-related molecules A and B (MICA/B) signaling system could be involved in host-parasite interactions; however, its involvement in helminthic diseases has never been studied . Methods. Westudied MICA/B, NKG2D, and transforming growth factor-β (TGF-β) expression on liver sections and measured levels of soluble MICA in serum samples obtained from patients with progressive AE. Livers from healthy and cirrhotic subjects were studied as controls. Results. Expression of MICA/B proteins was strongly enhanced in the hepatocytes and endothelial and bile duct cells; in the CD68+ cells of the periparasitic infiltrate, especially epithelioid and giant cells; and, also, in the metacestode germinal layer. Strong expression of MICA/B in the liver contrasted with low numbers of NK cells and lack of expression of NKG2D on the numerous CD8+ T lymphocytes of the periparasitic infiltrate, as well as with the absence of soluble MICA in serum. TGF-β was strongly expressed by most of the infiltrating lymphocytes. Conclusions. Sustained expression of MICA/B molecules and TGF-β might lead to modulation of NKG2D with subsequent inhibition of NKG2D-dependent cytotoxicity. Abnormalities of this signaling system could contribute to parasitic evasion of the host's immunity. [ABSTRACT FROM AUTHOR]

Previous studies have shown that antibodies from humans exposed continuously to malaria recognize the Plasmodium falciparum asexual blood-stage antigen Pf332. Here we analysed the antibody responses to a C-terminal fragment of Pf332, designated C231, in individuals from Senegal, by measuring the serum levels of immunoglobulin M (IgM), IgG class and subclass and IgE antibodies. IgG antibody reactivity with crude P. falciparum antigen was detected in all the donors, while many of the children lacked or had low levels of such antibodies against C231. The antibody levels increased significantly with age for both crude P. falciparum antigen and C231, and in the older age groups most of the donors displayed antibodies to C231. This was also true for IgM, IgE and IgG subclass reactivity against C231. Moreover, the ratio of IgG1/IgG2 was considerably lower for C231 than for crude P. falciparum antigen, and in age groups 10–14 and 15–19 years the levels of IgG2 against C231 even exceeded that of IgG1. The IgG2/IgG3 ratios suggest that C231 gives similar levels of IgG2 and IgG3, except for children aged 4–9 years, where IgG3 was higher. Raw IgM, IgG class and subclass and IgE antibody levels to C231 tended to be higher in those who did not experience a malaria attack, but following linear multivariate analysis the trends were not significant. [ABSTRACT FROM AUTHOR]

The humoral response to the gastrointestinal (GI) flora was analyzed in secretory Ig (sIg)-deficient polymeric IgR (pIgR)−/− mice and otherwise congenic C57BL/6 mice. While both strains carried an ileal flora of similar size and composition, increased bacterial translocation to mesenteric lymph node was demonstrated in pIgR−/− mice. Serum IgA was greatly increased in pIgR−/− mice compared with C57BL/6 mice and reacted with commensal organisms and food. Serum IgG levels in pIgR−/− mice were increased to 6-fold above that of C57BL/6 mice and included specificities that bound to selected flora antigens. The enhanced recognition of flora antigens in pIgR−/− mice was explored using ovalbumin (OVA)-specific CD4+ T cells and feeding of low concentrations of OVA. Increased proliferation of transgenic T cells was observed in pIgR−/− mice, relative to C57BL/6 mice, suggesting elevated net uptake of protein antigens from the GI tract in the absence of sIg. These studies suggest that there is increased recognition of GI flora antigens by systemic antibodies in pIgR−/− mice, most probably as a result of increased access of antigens from the GI flora to the systemic immune compartment, and support the hypothesis that a major function of the secretory immune system is to return environmental antigens to mucosal surfaces. [ABSTRACT FROM AUTHOR]

Mucous membrane pemphigoid (MMP) (also known as cicatricial pemphigoid) is a rare autoimmune mucocutaneous blistering disease that affects mucous membranes derived from stratified squamous epithelium and the skin. A subset of MMP affects only the oral cavity and is referred to as the oral pemphigoid (OP). MMP and OP are characterized by subepithelial vesicles on histology and in vivo deposition of immunoglobulins and complement at the basement membrane zone (BMZ) on immunopathology. Previous studies have shown that sera of patients with MMP bind to human integrin β4, while sera of patients with oral pemphigoid bind to the integrin α6 component of the heterodimer. The prognosis in MMP is grave but excellent in OP. In this study we compare the binding of sera from patients with OP from Boston, MA, USA to Naples, Italy, and attempt to identify an epitope to which the anti-integrin α6 human autoantibody binds. Our results indicate that the sera from Boston and Naples are identical in their reactivity. They recognize a fragment I (AA 23–462) and its subfragment IB (AA 217–462) only, in the human integrin α6 molecule. Blocking studies, immunoprecipitation and immunoabsorbtion studies confirm the presence of this single 245 AA region. Antibodies to subfragment IB cause BMZ separation in organ culture using normal human oral mucosa as substrate. This preliminary study indicates that patients on both continents may have similar reactivity and suggests that an intercontinental study group could be established to advance our understanding of the pathogenesis of OP and the biology of anti-α6 integrin autoantibodies. [ABSTRACT FROM AUTHOR]

A spectrum of in vivo-expressed Staphylococcus aureus antigens was identified by probing bacteriophage expression libraries of S. aureus with serum samples from infected and uninfected individuals. Eleven recombinant antigenic proteins were produced, and specific antibody titers in a large collection of human serum samples were determined. Significantly increased concentrations of reactive immunoglobulin G (IgG) to 7 antigens were found in serum samples from ill individuals, compared with those in healthy individuals. Significantly higher concentrations of reactive IgG to 4 antigens, including iron-responsive surface determinant (Isd) A and IsdH, were found in serum samples from healthy individuals who were not nasal carriers of S. aureus, compared with those in healthy carriers. Vaccination of cotton rats with IsdA or IsdH protected against nasal carriage. Also, IsdA is involved in adherence of S. aureus to human desquamated nasal epithelial cells and is required for nasal colonization in the cotton rat model. Thus, vaccination with these antigens may prevent S. aureus carriage and reduce the prevalence of human disease. [ABSTRACT FROM AUTHOR]

Epstein-Barr Virus (EBV)-transformed B lymphoblastoid cell lines (BLCL) are currently used for numerous applications in cellular immunology. Where protocols destined for clinical application are concerned, the final choice of assay is made according to a risk/benefit ratio analysis. In this balance the use of xenogenic or allogenic serum has always been a major concern, as it carries both an infectious and an immunological risk. So far, it is unknown whether serum can be omitted from the entire BLCL selection procedure. In addition, as BLCL have been described as heterogeneous, serum deprivation may affect their antigen-presenting capacity. In the present study, BLCL were generated in the absence or presence of fetal calf serum (referred to as BLCL0 or BLCLFCS, respectively). Next, in order to assess the antigen-presenting capacity of these cells, we compared the ability of BLCL0 and BLCLFCS cells to stimulate the EBV-specific repertoire of the corresponding donor's peripheral blood mononuclear cells in vitro. Our results showed that addition of serum was not essential for BLCL infection and culture, and that as far as we could determine, BLCL0 cells were as effective as BLCLFCS in reactivating the EBV-specific T-cell repertoire in vitro. Notably, FCS-specific T-lymphocytes can be detected among the BLCLFCS-specific CD4+-CTL. Not only was this latter observation unexpected for an EBV-seropositive donor, but it implied that the BLCL had captured and processed the corresponding FCS-derived solubles antigens; taken together our results emphasized the interest of the possibility to generate BLCL0, both for research and for clinical applications. [ABSTRACT FROM AUTHOR]

To serologically determine the association of microbial superantigens and the pathogenesis of Kawasaki disease (KD), we conducted a case-control study. Serum IgG and IgM antibodies against staphylococcal enterotoxin A (SEA), SEB, SEC, toxic shock syndrome toxin-1 (TSST-1), and streptococcal pyrogenic exotoxin A (SPEA) were measured by an enzyme-linked immunosorbent assay in 293 serum samples from 65 KD patients on clinical days 1–28 and 120 control samples. The administration of immunoglobulin products, which contain high concentrations of IgG antibodies against all the superantigens, directly elevated antitoxin IgG antibodies in KD patients. In contrast, antitoxin IgM antibodies were not detected in immunoglobulin products. Actually, we found a significant elevation of IgM antibodies against SEA in KD patients in the first (median titre: 0·020, P < 0·01 versus control), second (0·024, P < 0·001), third (0·030, P < 0·001) and fourth (0·038, P < 0·001) weeks, compared to the controls (0·015). Significant differences of IgM antibodies were also true for SEB, TSST-1, and SPEA throughout the first to fourth weeks, and for SEC throughout the second to fourth weeks. The prevalence of KD patients having high IgM titres (> mean + 2SD of control values) to the 5 superantigens was increased with the clinical weeks, and reached 29–43% of KD subjects at the fourth week. This is the first study that describes kinetics of IgM antibodies against superantigens and clarifies the serological significance throughout the clinical course of KD. Our results suggest that multiple superantigens involve in the pathogenesis of KD. [ABSTRACT FROM AUTHOR]

Background Cryptococcal meningoencephalitis (CM) affects individuals with AIDS, transplants recipients and those previously healthy, with 30–50% mortality in most groups despite anti-fungal treatment. In the previously healthy, a post-infectious inflammatory response syndrome (PIIRS) analogous to cryptococcal IRIS in AIDS patients has recently been described. PIIRS is defined as a deterioration in mental status and/or audio-visual capacity despite optimal treatment for CM and negative CSF cultures. Pathophysiology is related to excessive T-cell responses to lysed fungal cells during therapy but data on effective treatment regimens are limited. Methods Between March 2015 and February 2019, 11 consecutive patients with PIIRS who evidenced clinical deterioration over a period of up to 10 weeks despite effective antifungals were referred to the NIH clinical center. Patients were prospectively treated with adjunctive pulse solumedrol 1 g daily for 1 week followed by prednisone 1 mg/kg/day, tapered based on clinical and radiological response plus oral fluconazole. Montreal cognitive assessments (MOCA) scores at baseline and 1 month were the primary endpoints and CSF parameters including WBC, glucose, HLA DR4+ CD4 and CD8 cells and cytokines were also determined at baseline and after 1 week of solumedrol. Paired nonparametric t -tests were conducted using GraphPad Prism 7.0. Results All patients demonstrated clinical improvement despite 7 being initiated at the point of stupor and 6 having received ventriculoperitoneal shunts without clinical response. MOCA scores at 1 month showed significant improvement (P = 0.002), accompanied by significant improvements in CSF: serum glucose ratios, CSF WBC, protein and HLADR4 positive T cells 1 week after receiving corticosteroids (P < 0.02). Patients with hearing or visual deficits exhibited clinical improvement. CSF cultures remained negative. Conclusion Our findings in this small observational cohort of refractory non-HIV CM with PIIRS demonstrated significant clinical benefit of high dose adjunctive pulse-taper corticosteroids. The study also demonstrates the utility of physiology-based immunophenotyping to guide therapy in neuroinflammation associated with infectious diseases. Disclosures All Authors: No reported Disclosures. [ABSTRACT FROM AUTHOR]

Substantial evidences suggested that propylthiouracil (PTU) could induced anti-myeloperoxidase (MPO) antibodies in sera from patients with hyperthyroidism, however, only a subgroup of the PTU-induced anti-MPO antibody positive patients developed clinical evident vasculitis. The aim of this study is to compare the titres and affinities of PTU induced anti-MPO antibodies in sera from patients with hyperthyroidism with and without clinical vasculitis. Anti-MPO antibody positive sera from patients diagnosed hyperthyroidism with ( n = 13) and without ( n = 14) clinical evident vasculitis were collected. The titre was determined by MPO-ELISA and expressed as logarithm value (lgT). The affinity constant (aK) of anti-MPO IgG was measured by antigen inhibition assay. The titre and aK values were compared between patients with and without vasculitis. In patients with vasculitis, the mean lgT of anti-MPO antibodies was 3·62 ± 0·66; the median aK was 4·47 × 107M−1. In patients without vasculitis, the mean lgT was 2·54 ± 0·29; the median aK was 0·14 × 107M−1, and both were significant lower than those in patients with vasculitis ( t = 5·464; P = 0·000 & z = −4·373; P= 0·000, respectively). We concluded that the titre and affinity of anti-MPO antibodies might be associated with the development of clinical vasculitis in patients with PTU-induced ANCA. [ABSTRACT FROM AUTHOR]

Background. Inhibition of the binding of Bacillus anthracis protective antigen (PA) to its cellular receptor can abrogate the downstream toxin-mediated deleterious effects of the anthrax toxin. A fully human monoclonal antibody against B. anthracis PA, PAmAb, was previously shown to provide a survival advantage in rabbit and monkey models of inhalational anthrax. Methods. A randomized, single-blind, placebo-controlled, dose-escalation study with 105 healthy volunteers was conducted to evaluate the safety, pharmacokinetics, and biological activity of PAmAb. Subjects received PAmAb or placebo as a single intramuscular injection (11 subjects/cohort) or intravenous infusion (10 subjects/cohort). Three intramuscular dose levels (0.3, 1.0, and 3.0 mg/kg) and 5 intravenous dose levels (1.0, 3.0, 10, 20, and 40 mg/kg) were studied. Two separate intramuscular injection sites (gluteus maximus and vastus lateralis) were evaluated in the cohorts (hereafter, the "TM-GM" and "IM-VL" cohorts, respectively). Results. PAmAb was well tolerated, with no dose-limiting adverse events. All adverse events were transient and mild to moderate in incidence and/or severity. The pharmacokinetics of PAmAb were linear within each route and site of administration but were significantly different between the TM-GM and IM-VL cohorts. The mean terminal elimination half-life ranged from 15 to 19 days. The bioavailability of PAmAb is ∼50% for TM-GM injection and 71%-85% for IM-VL injection. The biological activity of PAmAb in serum, assessed using a cyclic adenosine monophosphate assay, correlated with serum concentrations. Conclusions. PAmAb is safe, well tolerated, and bio available after a single intramuscular or intravenous dose, which supports further clinical development of PAmAb as a novel therapeutic agent for inhalational anthrax. [ABSTRACT FROM AUTHOR]

Serum samples from 31 children ≤4 years old who were convalescing after meningococcal disease were used in a quantitative hybridization assay to establish antibody reactivity to 94 candidate meningococcal vaccine antigens. Genes encoding 22 of 23 strongly recognized proteins were found in ≥94% of the patients' meningococcal strains, and most were also widely prevalent in Neisseria lactamica and other commensal Neisseria species. Similar antibody reactivity was found in serum samples from healthy control children, suggesting that these antibodies arose from asymptomatic colonization. The 23rd protein, NadA, elicited strong reactivity solely in convalescent patients previously infected with a nadA+ strain. nadA was not present in any of 29 diverse N. lactamica strains, suggesting that reactivity in these children arose from meningococcal infection. In contrast, serum samples from healthy adults contained anti-NadA immunoglobulin G at high levels. The correlation of NadA antibody level with natural acquisition of protective immunity suggests that NadA may be a valuable component of a childhood antimeningococcal vaccine. [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome (SARS) coronavirus (SCoV) spike (S) protein is the major surface antigen of the virus and is responsible for receptor binding and the generation of neutralizing antibody. To investigate SCoV S protein, full-length and individual domains of S protein were expressed on the surface of insect cells and were characterized for cleavability and reactivity with serum samples obtained from patients during the convalescent phase of SARS. S protein could be cleaved by exogenous trypsin but not by coexpressed furin, suggesting that the protein is not normally processed during infection. Reactivity was evident by both flow cytometry and Western blot assays, but the pattern of reactivity varied according to assay and sequence of the antigen. The antibody response to SCoV S protein involves antibodies to both linear and conformational epitopes, with linear epitopes associated with the carboxyl domain and conformational epitopes associated with the amino terminal domain. Recombinant SCoV S protein appears to be a suitable antigen for the development of an efficient and sensitive diagnostic test for SARS, but our data suggest that assay format and choice of S antigen are important considerations. [ABSTRACT FROM AUTHOR]

Little is known about the prevalence and clinical significance of infection with Encephalitozoon species in immunocompetent individuals. In the present study, by using indirect immunofluorescence technique (IFAT), Western blot, and recombinant antigens of the spore wall (SWP1) and polar tube (PTP1, PTP2, and PTP3), we analyzed the IgG antibody response of a laboratory worker who was infected with Encephalitozoon cuniculi. Serum samples were analyzed 1, 20, 32, and 38 months after infection. After 1 month, by use of IFAT, only spore-wall antigens were recognized, an antibody reaction that changed toward both the spore wall and polar tube in the following months. By use of Western blot analysis, a characteristic pattern that recognized multiple bands was noticed. Reaction against SWP1 was present in all 4 serum samples. The IgG response against PTP1, PTP2, and PTP3 was not detectable 1 month after infection, but became evident in the follow-up serum samples. Serum samples showed cross-reactivity with the spore wall of Encephalitozoon hellem and Encephalitozoon intestinalis, but only little cross-reactivity with the polar tube of these parasites. This is the first study to our knowledge that provides full details about the antibody response against a specified Encephalitozoon species in an immunocompetent person. The results strongly encourage the development and use of reliable serodiagnostic methods, which will provide information about the prevalence and clinical significance of Encephalitozoon species infection in humans. [ABSTRACT FROM AUTHOR]

Objectives: In 2001, we proposed the criteria for combined evaluation of the serum carcinoembryonic antigen (CEA) level and the tumor shadow disappearance rate (TDR) to predict pathologic N0 (pN0) disease in pulmonary adenocarcinomas. The objective of the present study was to determine the prognosis and histologic features in small-sized pulmonary adenocarcinomas according to serum CEA level and TDR. Methods: We reviewed clinical records of 189 consecutive patients with peripheral pulmonary adenocarcinoma 3.0 cm or smaller who underwent major lung resection and systematic lymph node dissection: 50 patients with TDR 0.8 or more and normal CEA level (group I) and 139 patients with TDR <0.8 and/or elevated CEA level (group II). Among them, we investigated histologic features of 177 adenocarcinomas according to serum CEA level and TDR. Results: The 5-year survival rates were 95% for group I and 75% for group II (P=0.002), and for pN0 patients, 97% in group I and 87% in group II (P=0.04). In univariate analyses, TDR, preoperative serum CEA level, and the maximum tumor dimension on computed tomographic (CT) scan were significantly associated with prognosis. Multivariate analysis showed that only preoperative serum CEA level and TDR were significant independent prognostic factors, and the maximum tumor dimension was not significant. Group I patients developed no local recurrence, including lymph node metastases. In 25 group I adenocarcinomas 2.0 cm or smaller, no lymph node involvement, two lymphatic permeation, two vascular invasion, and one pleural involvement tumors were observed. These signs of local invasiveness were less frequent than the remaining adenocarcinomas. CT findings correlated well with histologic findings in small-sized adenocarcinomas. Conclusions: Combined evaluation of preoperative serum CEA level and TDR may enable us to identify minimally invasive adenocarcinomas with good prognosis. Candidates for limited lung resection without systematic lymph node dissection could be selected based on these findings. [Copyright &y& Elsevier]

We conducted a retrospective, multicenter study evaluating the safety of discontinuing maintenance therapy for cryptococcal meningitis after immune reconstitution. Inclusion criteria were a previous definitive diagnosis of cryptococcal meningitis, a CD4 cell count of >100 cells/µL while receiving highly active antiretroviral therapy (HAART), and the subsequent discontinuation of maintenance therapy for cryptococcal meningitis. The primary end point was relapse of cryptococcal disease. As of July 2002, 100 patients were enrolled. When maintenance therapy was discontinued, the median CD4 cell count was 259 cells/m L and the median plasma virus load was <2.30 log[sub10] copies/mL, and serum cryptococcal antigen was undetectable in 56 patients. During a median follow-up period of 28.4 months (range, 6.7--64.5; 262 person-years), 4 events were observed (incidence, 1.53 events per 100 person-years; 95% confidence interval, 0.42--3.92). Three of these patients had a CD4 cell count of >100 cells/ m L and a positive serum cryptococcal antigen test result during the recurrent episode. In conclusion, discontin-uation of maintenance therapy for cryptococcal meningitis is safe if the CD4 cell count increases to 1 100 cells/ m L while receiving HAART. Recurrent cryptococcal infection should be suspected in patients whose serum cryptococcal antigen test results revert back to positive after discontinuation of maintenance therapy. [ABSTRACT FROM AUTHOR]

Examines the structural requirements for intersubtype antigenicity of HIV type 1 third variable envelope region (V3) using synthetic peptides in enzyme immunoassays with serum samples from persons with proven or probable subtype B and D infections. Effects of single-amino acid substitutions in amino-terminal half of V3; Virus neutralization assays; Effects of substitution combinations on antigenicity.

The open reading frame of human proteinase 3(PR3) without the prepro-peptide was cloned and expressed in Escherichia coli (rcPR3) and in Pichia pastoris (rpPR3). The 6-histidine tagged rpPR3 was efficiently secreted into culture supernatant from which it could be purified by immobilized metal chelate chromatography. Purified rpPR3 migrated as a single 32-kD band on SDS-PAGE and harboured protease activity that could be inhibited with inhibitors specific for serine-proteases. By indirect antigen-capture ELISA using rpPR3, 60% of sera from patients with Wegener's granulomatosis bound to the recombinant product, although it was not recognized in ELISA with directly coated rpPR3. [ABSTRACT FROM AUTHOR]

The objective of this study was to characterize antigens recognized by neutrophil-specific autoantibodies from patients with RA. .sera from 62 RA patients were screened by indirect immunofluorescence (IIF). Positive sera were further tested by ELISAs for antibodies against various granule proteins and by immunoblotting of eleetrophoretically separated cell, granule or nuclear extracts. Forty-two sera (68%) reacted with ethanol-fixed neutrophils. In the ELISAs 32% of the 28 medium to .strongly IIF-positive sera were negative, while 43% were weakly positive for more than one antigen. Immunoblots of whole neutrophils showed IgG reactions at 25-35 kD, in the 55-kD region, at 80 kD. and at 110 kD. Most sera reacted with more than one band. Except for the 55-kD antigen, none of the antigens appeared in lymphocytes. The most notable reactivity in subcellular fractions was with lactoferrin and with bands of 25-35 kD from nuclei. In conclusion, anti-neutrophil autoantibodies from RA patients recognize different antigens in the cytoplasm and in the nucleus. Lactoferrin is one of the common antigens recognized, but also unknown nuclear antigens of 25-35 kD mol. wt are involved. [ABSTRACT FROM AUTHOR]

Control of IgG immune complex formation and deposition is important in determining the nature and extent of subsequent immune effector responses, and appears to be aberrant in some autoimmune diseases. In this study we demonstrate that recombinant soluble FC³RII (rsFc7RII) is an effective modulator of immune complex formation, delaying immune recipitation in a manner which is dose-dependent, and can be specifically inhibited by anti-FcyRII MoAb Fab' fragments. This inhibitory role in immune precipitation also provides a possible mechanistic explanation for our previous demonstration of the efficacy or rsFc7RII as an inhibitor of immune complex-induced inflammation in the Arthus reaction in vivo. RsFc³RII inhibited immune complex precipitation in two different experimental systems. First, rsFc7RII inhibited the precipitation of 125I-bovine serum albumin (BSA)-anti-BSA complexes in a dose-dependent manner, while an irrelevant protein (soybean trypsin inhibitor) had no effect on the precipitation of the immune complexes. Moreover. RsFc³RII inhibited the precipitation of ovalbumin (OVA)- anti-OVA complexes as determined by lurbidimetric analysis, where the inhibition of immune complex precipitation by rsFc³RII was dose-dependent and was specifically blocked by prior incubation with Fab' fragments of a blocking MoAb to FC³RII. RSFC³RII could inhibit the precipitation of BSA-anti-BSA complexes in the presence of excess bystander IgG and did not inhibit complement-mediated prevention of immune precipitation, demonstrating that rsFc³RII did not block Cl binding to the BSA-anti-BSA complex. Unlike complement, rsFc³RII could not cause re-solubilization of pre-formed precipitated BSA-anti-BSA complexes. Soluble FC³RS have been detected in biological fluids of normal and inflammatory disease patients, yet the role of SFC³R is still unclear. However, they now play a potential role in the modulation of immune complex solubility. [ABSTRACT FROM AUTHOR]

Defined immune complexes (IC) were used to eompare the effect of antibodies of different classes and subclasses on neutrophil respiratory burst and degranulation. IC were made from 5-iodo-4- hydroxy-3-nitrophcnacetyl (NIP) conjugated to bovine scrum albumin (BSA) and chimacric mouse-human anti-NIP monoclonal antibodies ineluding lgA2, IgE and all four IgG subclasses. The activation of neutrophils by IC depended on antibody class and subclass, on antigen epitope density, on antigen : antibody ratio and on the medium used. The ability to generate the respiratory burst showed a different pattern to the ability to give rise to degranulation. Compared with other IC, IgA2 IC provided the strongest stimulus for neutrophil activation. IgG 1 IC, lgG2 IC and lgG4 IC activated neutrophils moderately or weakly. IgG3 IC were unable to stimulate the respiratory burst, but could cause strong degranulation. IgE IC could hardly cause any neutrophil response. Neutrophil degranulation in response to IgG3 IC in serum-free medium or heat-inactivated serum was fast, and it quickly reached maximum. Degranulation caused by !gA IC was relatively slow, but gradually increased during incubation. The activity of IgGl IC, IgG2 IC and IgG4 IC generated a respiratory burst increased with antibody excess and decreased with antigen excess. The activity of IgA2 IC, however, was not affected by change of antigen and antibody ratio. A specific role of serum, possibly due to complement, was found in enhancing degranulation, both temporally and quantitatively, by lgA2 IC. [ABSTRACT FROM AUTHOR]

Decay accelerating factor (DAF), membrane cofactor protein (MCP), complement receptor 1 and mouse Crry are cell surface-bound complement regulatory proteins capable of inhibiting C3 convertase activity on cell membranes, and therefore provide a substantial protection from attack by homologous complement activated either by the classical or by the alternative pathway. Decrease in complement regulatory activity might lead to spontaneous complement deposition and subsequent cell injury. MoAb 512 can inhibit the complement regulatory activity of molecules on rat cells, resulting in deposition of homologous complement. The antigen recognized by 512 MoAb in rats is homologous to mouse Crry. Fifteen to 20 h after infection with vaccinia virus, in vitro cultured KDH-8 rat hepatoma cells show a strong decrease in expression of Crry-like antigen, and proved to be sensitive to complement deposition when 1:5 diluted normal rat serum was added to the culture medium as a source of complement. Addition of complement to the cultured KDH-8 cells infected with a very low dose of vaccinia virus (I plaque-forming unit (PFU)/1000 cells) substantially reduced spreading of virus infection in the cell culture, while inactivation of complement by heat or zymozan treatment abrogated the protective effect. [ABSTRACT FROM AUTHOR]

A chance observation has led to the discovery of a strain of PVG rats (PVG/c-) which are deficient in complement (C) component C6. Analysis of total haemolytic activity (CH50) of PVG/c- serum revealed an absent CH50 activity compared with serum of other rat strains and of a PVG/c rat (PVG/c+) that showed normal C activity. Thus, the PVG/c- rat was unable to activate the C5b-9 membrane attack complex. To gain insight into the complement abnormalities, analysis of individual C components was performed. Testing the PVG/c- serum in a C6 haemolytic assay and using deficient human sera showed a deficiency of C6 in the PVG/c- rat. Highly purified human C6 and human sera deficient in other components were able to reconstitute the CH50 activity of the PVG/c- rat. The possibility that an inactivator of C was present in PVG/c- serum was excluded. The deficiency was found to he inheritable and under the control of an autosomal recessive gene. Furthermore, tissue antigens and immunity of the PVG/c- rat were found to be identical to those determined in the PVG/c+ rat. With regard to their health status, the PVG/c- animals seem to have no disadvantages compared with PVG/c- rats when held under the same conditions within the protected environment of animal facilities. Taken together. both rat strains provide an unique animal model for studying the biological role of C, particularly the C5b-9 membrane attack complex in experimental medicine. [ABSTRACT FROM AUTHOR]

To study the role of anti-idiotypic antibodies in the regulation of the immune response to Lol p I (the major allergenic component of rye grass pollen), we have recently generated a panel of three MoAbs directed against distinct epitopes of Lol p I and an anti-idiotypic MoAb directed against the idiotype borne by one of the anti-Lol p I MoAbs (290A-I67). The effects of pretreatment with this anti-idiotypic MoAb in BALB/c mice before immunization with the antigen have been examined. The anti-idiotypic MoAb or unrelated MoAb were given weekly for 8 weeks intraperitoneally. Mice then received the antigen (2 μg) adsorbed with alum (2 mg) at weeks 9, 11 and 13. Serum anti-Lol p I antibodies (IgG or IgE) and specific idiotypic responses were measured. Anti-Lol p I IgG antibodies could be detected before immunization with Lol p I only in mice pretreated with anti-idiotypic MoAb. Immunization with Lol p I induced an anti-Lol p I IgG response in both groups, but this response was higher in mice that received anti-idiotypic MoAb. Similar profiles were seen for specific IgE antibodies and idiotypic responses. Surprisingly, idiotypes borne by other anti-Lol p I MoAbs (539A-6 and 348A-6) had also been enhanced after pretreatment with the anti-290A-167 MoAb. These observations suggested that the pretreatment with this anti-idiotypic MoAb modulates not only the expression of the respective idiotype, but also affects other idiotype responses. [ABSTRACT FROM AUTHOR]

The ubiquitotis Sm polypeptides B/B' (28 and 29 kD) and the highly homologous tissue-specific Sm N polypeptide (29 kD) share several autoepitopes recognized by systemic lupus erythematosus (SLE) sera. Previous studies on the antigenicity of nuclear antigens recognized by human autoantibodies have not discriminated between ubiquitous and tissue-specific forms. We set out to examine whether a tissue-specific nuclear antigen, Sm N, is autoantigenic in SLE by comparing the immunoreactivity of the most unique sequences in this polypeptide. Synthetic peptides from the two regions of least sequence homology that occur between Sm N and Sm B/B', a dodecamer (amino acid residues 179-190 containing five substitutions) and an undecamer (residues 203-213 containing four substitutions) were coupled to a carrier protein. These conjugates were used to quantify IgG anti-peptide antibodies in sera from patients with SLE, Of 43 sera with anti-Sm specificity, six bound to the B/B' 179-190 peptide but not to the N version. None of 17 anti-Sm-negative SLE sera bound these peptides. The second region of least sequence homology between N and B/B' (203-213) was not antigenic. Our data suggest that a subset of SLE patients with anti-Sm reactivity have IgG autoantibodies capable of discriminating between Sm N and SmB/B' polypeptides by binding a previously unreported SmB/B' specific autoepitope. The data also indicate that brain and heart-specific anti-Sm antibodies do not exist in SLE sera, suggesting that these tissues do not participate in the induction or maintenance of the autoimmune anti-Sm response. [ABSTRACT FROM AUTHOR]

Thyroglobulin (TG) and thyroperoxidase (TPO), both involved in thyroid hormone synthesis, represent major autoantigens in thyroid autoimmune disease. Despite numerous studies, the emergence, pathophysiological significance and role of autoantibodies to TG and TPO remain elusive. The recent identification of a new category of thyroid-specific autoantibody interacting with both TG and TPO (TGPO autoantibodies) offers a new opportunity in the study of thyroid autoimmunity. To gain a better insight into the significance of these TGPO autoantibodies. measurement in individual samples appeared necessary. The unique property of TGPO autoantibodies, simultaneous binding to TG and TPO, was used to set up a sandwich method which combined coated TG and radio-iodinated TPO. This method was found to be strictly specific for TGPO autoantibodies and sensitive enough to assay TGPO autoantibodies in serum. In humans, TGPO autoantibodies were found in most of the sera with high TG and TPO autoantibody titres, but not in sera negative for TG autoantibodies, whatever the TPO autoantibody titre. Furthermore, high TGPO autoantibody titres were found in sera strongly cytotoxic for cultured porcine thyroid cells. However, significant correlation of TGPO autoantibody titre was observed neither with TG and TPO autoantibody titres (n = 48) nor with complement-dependent cytotoxicity (n = 50). TGPO antibody assay was also performed in individual plasma of CBA/J mice immunized with either human TG (n = 6) or human TPO (n = 6). Immunization with TG induced high levels of not only TG but also TGPO antibodies, which exhibited a strong reactivity for TPO and whose binding to TG and TPO was fully inhibited by TG. In contrast, immunization with TPO induced high levels of only specific TPO antibodies accompanied by low levels of specific TG antibodies. In this case TGPO antibodies were not detected. Of note, TG- and TPO-immunized mice mounted an immune response against their own TG, but did not exhibit histologieal signs of thyroiditis. Large panels of TG and TPO MoAbs were also investigated with this method: 18/25 TG MoAbs and only 1/13 TPO MoAbs were found cross-reactive. Taken together, these data provide evidence that TGPO antibodies are effectively present in individual patients and TG-immunized mice, are different from specific TG and TPO antibodies, and may derive from natural B cell repertoire by autoimmune processes involving TG and not TPO. [ABSTRACT FROM AUTHOR]

A proportion of patients with atopic dermatitis have elevated serum levels of IgG4. In order to investigate further this abnormality of IgG subclass production, atopic patients were immunized with the protein antigen keyhole limpet haemocyanin (KLH), and IgG subclass responses following primary and secondary immunization were analysed. In the primary response, titres of IgG1, 2 and 3 antibodies were lower in the atopic patients than in the controls. In contrast, titres of IgG4 were much higher for the patient group. In both patients and controls, the kinetics of IgG4 antibody production following the initial immunization with KLH showed a slow rise reaching a peak at 30 weeks. This time course indicated that the high IgG4 response was unlikely to be due to previous exposure of the patients to a cross-reacting antigen. A higher proportion of IgG4 was also seen in the atopic patients following secondary immunization; indeed, IgG4 was the major subclass in the secondary response in the patient group. In the controls, but not in the patients, titres of tgG4 anti-KLH correlated with total serum levels of IgG4, and some of the highest IgG4 antibody responses were detected in atopic patients whose serum IgG4 concentration was in the normal range. The results suggest that raised serum levels of IgG4 in atopy may reflect abnormal isotype regulation in response to protein antigens. [ABSTRACT FROM AUTHOR]

Paired sera were obtained before and 8 weeks after routine BCG vaccination from 20 PPD-S Mantoux-negative individuals who were living adjacent to the Chingleput BCG vaccine trial area in Tamil Nadu and from seven Mantoux-negative school-children in London, UK. Most subjects became Mantoux-positive after vaccination. In ELISA tests against soluble extracts of BCG or Mycobacterium tuberculosis H37Rv or against PPD-S, pre-vaccination antibody titres of South Indian subjects were about twice those of British subjects but there was no increase in titre of antibodies after vaccination of either population. Western blotting showed that even before vaccination, and even in British subjects, antibodies were present that recognized numerous antigenic components in extracts of BCG and M. tuberculosis. There was no consistent difference between band patterns with South Indian and British subjects and any effect of vaccination on the patterns was minimal. [ABSTRACT FROM AUTHOR]

We compared the time course of changes in serum levels of circulating immune complexes (CICs) and of IgG antibody after sensitization of albino Lewis and pigmented Lister strain rats with uveitogenic (retinal S-antigen) and non-uveitogenic (ovalbumin) protein antigens of comparable molecular weight. Normal levels of CICs were far lower in Lewis rats in which experimental autoimmune uveoretinitis (EAU) takes the form of a severe panuveitis, than in Lister rats, in which the disease is mild, focal, confined to the posterior segment, and of lower incidence. After sensitization with either S-antigen or ovalbumin. polyethylene-glycol-precipitable CIC (PEG-CIC) peaked and fell as IgG antibody levels rose in both rat strains, However, peak levels of PEG-CIC were lower and subsequent IgG antibody levels were higher in the Lewis strain than in the less susceptible Lister strain. In both strains of rat these linked PEG-CIC/IgG antibody responses occurred earlier after sensitization with uveitogenic (S-) antigen than with ovalbumin, whether or not individual S-antigen-sensitized Lister rats developed EAU. In contrast, complement-binding CIC rose substantially only in those rats of both strains displaying EAU in response lo S-antigen and not in response to ovalbumin. We suggest that immune complex (idiotypic) regulation of IgG antibody responses may be more readily perturbed by a pathogenic autoantigen (S-antigen) than by a bland antigen (ovalbumin). We also suggest that differences between the balance of regulatory and pathogenic CIC responses to uveitogenic retinal antigen may underlie or reflect strain differences in susceptibility to and severity of EAU. [ABSTRACT FROM AUTHOR]

The availability of MoAbs now allows the accurate quantification of the individual C4 isotypes. C4A and C4B. Using a sensitive two-site immunoradiometric technique to measure serum levels of C4A and C4B, we studied the relationship between genotype and phenotype and physiological factors affecting C4 expression in 129 fully genotyped healthy subjects. Our results confirm that there is extensive phenotypic overlap between genotypic groups and it was not possible to determine the presence of single null alleles from total serum C4. Of the factors which may influence C4 expression, we found that age contributes a very small influence but that gender has no effect and there was no evidence for the presence of feedback of null alleles on the expression of remaining genes. Potential problems in quantifying C4 arising from the complex relationship between isotypic identity and serotypic recognition were highlighted by the finding of reversed antigenic expression of a C4B*5 molecule which was recognized as C4A by the anti-Rg:1 monoclonal used in these studies. We also confirmed that the extended MHC haplotype associated with Felty's syndrome, HLA-B44, C4A*3, C4BQ*O, HLA-DR4, encodes an expressed, duplicated. C4A gene. [ABSTRACT FROM AUTHOR]

Several distinct T helper (TH) subsets have been identified, based on the cytokines secreted. Recently, it has been demonstrated that these subsets can regulate the isotype of humoral responses. To investigate the possible differences in TH subsets between atopic donors which have elevated serum IgE and donors with normal serum IgE, we examined series of human TH cell clones. A total of 31 and 22 CD4+ T cell clones from the atopic and non-atopic donors, respectively, were characterized for the ability to help for IgE synthesis in vitro. T cell clones generated with allergen AgE from the atopic donor were autoreactive and all induced IgE synthesis. Tetanus toxoid-specific (TT) and phytohaemagglutinin clones were generated from both donors. There was significant heterogeneity between the T cells isolated with different stimuli from the same atopic donor. Also, there was a significant difference in the number of T cells generated from the atopic versus the non-atopic donor which helped for IgE, although there was no significant difference between the total number of T cells able to help for immunoglobulin synthesis of other isotypes. Most importantly, there was a higher frequency of clones able to support IgB synthesis between TT-specific T cell clones generated from the atopic versus the non-atopic donor. These results suggest that there are changes in subsets of TH cells specific for microbial antigens as well as allergens in atopics, which may have important implications for the aetiology of atopic disease. [ABSTRACT FROM AUTHOR]

Specific IgM and IgG responses to Paracoccidioides brasiliensis produced in resistant and susceptible mice during experimental paracoceidioidomycosis were examined by the immunoblotting procedure. Sera from infected mice recognized 51 antigen bands with apparent molecular masses from 8 to 86 kD, Sixteen of these were defined as major antigen bands because of almost universal presence of antibodies to them, and their intense staining. All sera, including those from normal control mice, tested for both IgM and IgG antibody reacted with the major E antigen which appeared as a large diffuse band from 43 to 47 kD. Comparisons between resistant and susceptible mice showed some significant differences in IgM responses to many antigen bands. While IgG responses were quite similar for both strains, differences were apparent in the response to the antigens at 62 and 68 kD. [ABSTRACT FROM AUTHOR]

Soluble CD8, soluble CD4, soluble CD25 (IL-2 receptor), β2-microglobulin and the cytokine tumour necrosis factor-alpha (TNF-α) were measured in sera from patients with common variable immunodeficiency (CVI), Levels of soluble CD8, soluble CD25 and β2-microglobulin but not of soluble CD4 and TNF-α were raised significantly above levels in normal sera. Sera from patients with X-linked agammaglobulinaemia, who are also antibody deficient, did not show this marked elevation. The raised levels of soluble CD8, soluble CD25 and β2-microglobulin in CVl, correlated with the extent of the defects in the B lymphocytes assessed in vitro, as well as with the clinical severity of the disease. The selective release of these molecules into sera may indicate that abnormal cellular activation occurs in most CVI patients. It is also possible that the raised levels of these soluble molecules play a part in the immunodeficiency. [ABSTRACT FROM AUTHOR]