Search

Investigation of the nature of the increased erythrocyte-antibody (EA) binding activity of peripheral blood lymphocytes (PHL) from rheumatoid arthritis (RA) patients reported in the preceding paper has revealed that IgG is the active class of antibody in this rosette formation. Some IgM binding also occurs. SRBC sensitized with F(ab)2 preparations of IgG do not give rosette formation even at high concentrations. EA binding is inhibited by prior incubation of lymphocytes with heat-aggregated human IgG but antigen-antibody complexes did not give significant inhibition. The majority of these rosettes were found to be stable at 4°C. and room temperature but labile at 37°C. Enzyme studies with pronase, trypsin, neuraminidase and treatment with sodium azide gave results strongly supporting the conclusion that the increased binding observed is increased Fc-receptor activity. This activity appears not to be a result of Fc binding by cell-bound rheumatoid factor. A range of titres of antibody and of IgG was used to sensitize erythroeytes to form EA and the enhanced EA-rosette formation by PBI, from RA patients occurred throughout the range of concentrations of sensitizing antibody. Significantly more EA were bound by individual lymphocytes from RA patients than control subjects. This data suggest that the Fc receptors on RA lymphocytes are more avid for FA than receptors on lymphocytes from healthy people. [ABSTRACT FROM AUTHOR]

In this paper the specificity of the skin-reactive guinea-pig immunoglobulin in the homologous PCA test has been reconsidered. Extensive purification of this immunoglobulin by chromatographic methods results in the isolation of a small fraction or medium speed immunoglobulins that contains all skin reactivity. No correlation could be found with the 7S immunoglobulins IgGγ1 and Igγ1A suggesting a separate class of biologically active immunoglobulins. The PCA active antibody belongs to either an IgG subclass or is a heat stable homocytotropic antibody. Rabbit and chicken antisera against isolated fractions of guinea-pig immunoglobulins show the existence of 7S subclasses. Some suggestions for a revised nomenclature are given. [ABSTRACT FROM AUTHOR]

IgG and IgE containing circulating immune complexes (CIC), total serum IgE and parasite related IgE were determined in monoinfected patients with Schistosoma mansoni or S. haematobium and in patients with a mixed infection. IgE- and IgG-CIC and total serum IgE were significantly higher in the mixed infection group. There is considerable cross-reactivity between the crude S. haematobium and S. mansoni antigen preparations. The level of IgE-CIC is correlated to the levels of total serum IgE and parasite related IgE respectively. Furthermore IgE-CIC levels were related to the intensity of infection. Twelve out of 21 patients suffering from a monoinfection were reinvestigated 1-4 months after specific chemotherapy. Parasi to logical cure is followed by a significant decrease of total serum IgE and IgE-CIC. whereas parasite related IgE did not change significantly. The importance of the disappearance of IgE-CIC is discussed. [ABSTRACT FROM AUTHOR]

Idiopathic nephrotic syndrome (iNS) with resistance or dependence to steroids is a common disease in children but in spite of an increasing clinical impact its pathogenesis is unknown. We screened for the presence of circulating antibodies against glomerular (podocytes, mesangium) and tubular cells (tubular epithelia) a cohort of 60 children with iNS including 8 patients with a familial trait of iNS or with proven mutation of NPHS1-NPHS2 and 12 with good sensitivity to steroids. Positive sera were found in 8 cases, all belonging to the category without familial trait/molecular defects. The targets of antibodies were characterized with Western blot and MALDI-Mass utilizing β-hexyl cell extracts separated with two-dimensional electrophoresis. In all cases antibodies of the IgM class were directed against ATP synthase β chain alone (4 cases) or in combination with actin (3 cases); one child presented IgG against aldose reductase. The clinical picture was nephrotic syndrome with steroid resistance or dependence and variable cyclosporin sensitivity; 3 patients developed end stage renal failure. The basic pathology picture was focal segmental glomerulosclerosis (FSGS) in 4 cases and mesangial proliferative glomerulonephrites with deposition of IgM in 2. Overall, patients with circulating auto-antibodies could not be readely differentiated on clinical grounds with the exception of 3 children who developed positivity for antinuclear antibodies during the follow-up. Affinity-purified IgM from one patient who underwent plasmapheresis for therapeutical pourposes (but not from a normal pool) induced proteinuria in Sprague-Dawley rats and concomitant human IgM deposition within glomeruli. This is the first report of circulating anti-actin/ATP synthase β chain antibodies in a subset of patients with iNS. Both pathological significance and clinical impact given by the presence of these antibodies and the relationship with other conditions such as lupus-erythematosus, characterized by their presence, must be defined. [ABSTRACT FROM AUTHOR]

The concentration of immunoglobulin classes G, M and A (IgG, IgM and IgA) in the sera of 233 aborted and 201 non-aborted foetuses was measured. IgM was first detected in a foetus at day 90 of gestation while IgG and IgA were first detected on day 111 of gestation, lmmunoglobulins were detected in 81.5% of aborted foetuses and 32.8% of non-aborted foetuses. Total immunoglobulin concentrations of 20 mg/l00 ml or greater were found in 35.2% of aborted foetuses but only in 4.5% of non-aborted foetuses. It is suggested that factors resulting in antigenic stimulation of tbe foetus may play an important part in bovine abortion. [ABSTRACT FROM AUTHOR]

Eighteen patients showing hypersensitivity to nitrofurantoin with symptoms like sudden fever, malaise, cough, pleuritis, leucocytosis and sometimes eosinophilia were analysed for immune reactions, i.e. lymphocyte transformation and specific antibodies. In addition, thirty-three individuals treated with the drug but with no clinical signs of the described reactions were included as controls. The lymphocyte transformation test (LTT) was found positive in ten out of the eighteen sensitive patients while one to three out of fourteen tested control patients were positive, depending on test conditions. An incubation period of 4 days in culture medium supplemented with autologous serum gave stimulation to a greater extent than did isologous serum and/or incubation for 6 days. The antibody determinations, with the enzyme-linked immunosorbent assay (ELISA), showed no IgE antibodies to nitrofurantoin in any of the patients. In contrast, most of the hypersensitive and even the control patients had specific IgG antibodies. The mean value of the antibodies of the sensitive group was higher than of the control group, but considerable overlapping between the groups was noted. In adverse reactions to nitrofurantoin a positive LTT and/or a high antibody titre to the drug favours an allergic mechanism and contributes to a more reliable diagnosis. [ABSTRACT FROM AUTHOR]

Five patients with no detectable serum IgA (<20 pg/mI) and one patient with low serum IgA were compared to normal subjects. The number of circulating E-RFC was normal as was the lymphocyte DNA synthesis induced by PHA, Con A, and streptokinase-streptodornase. The patients had normal numbers of IgA-bearing lymphocytes and normal or increased numbers of B cells. Purified anti-immunoglobulin antibodies specific for IgG, IgA and 1gM induced a normal lymphocyte DNA synthesis as did PWM. The patients' lymphocytes were able in vitro to trans- form into actively secreting 1gA plasmocytes. This transformation was determined by counting the IgA and immunoglobulin-containing cells and then measuring the IgA and IgU secretion in the cultures. In some patients PWM was selectively suppressive in IgA B-cell transformation into IgA secreting cells; in the other patients PWM had no effect on the IgA B-cell differentiation. PWM enhanced the IgG secretion in the patients' cultures as well as IgA and IgG secretion in the normal controls. Five patients with no detectable serum IgA (<20 pg/mI) and one patient with low serum IgA were compared to normal subjects. The number of circulating E-RFC was normal as was the lymphocyte DNA synthesis induced by PHA, Con A, and streptokinase-streptodornase. The patients had normal numbers of IgA-bearing lymphocytes and normal or increased numbers of B cells. Purified anti-immunoglobulin antibodies specific for IgG, IgA and 1gM induced a normal lymphocyte DNA synthesis as did PWM. The patients' lymphocytes were able in vitro to transform into actively secreting 1gA plasmocytes. This transformation was determined by counting the IgA and immunoglobulin-containing cells and then measuring the IgA and IgU secretion in the cultures. In some patients PWM was selectively suppressive in IgA B-cell transformation into IgA secreting cells; in the other patients PWM had no effect on the IgA B-cell differentiation. PWM enhanced the IgG secretion in the patients' cultures as well as IgA and IgG secretion in the normal controls. [ABSTRACT FROM AUTHOR]

Membrane-fixed IgG on isolated hepatocytes from biopsy material could be demonstrated by direct immunoflourescence in nine of thirty-four patients with acute virus-B hepatitis and in seventeen of forty-nine cases with chronic active hepatitis (CAH). Patients with acute virus-A hepatitis, chronic persistent hepatitis (CPH) or metabolic liver disease did not show this phenomenon. Cases with CAH and IgG on the hepatocytes - HB2 Ag-positive as well as HB2 Ag-negative - had high inflammatory activity. Antibodies against HB2Ag were not present in any serum. Autoimmune phenomena (antibodies against smooth muscle, mitochondria and nuclei) were only rarely demonstrable. The findings suggest that an antibody, or immune complex-mediated lymphocyte cytotoxicity may be involved in the pathogenesis of chronic liver diseases. [ABSTRACT FROM AUTHOR]

It has been previously reported that CH1 Fab protein G-contact site is responsible for the widespread recognition of mouse and human IgG Fab by PG. Here we present evidence that PG binding to F(ab′)2 is restricted, as indicated by the lack of reactivity with PG-Sepharose columns of a portion of F(ab′)2 fragments obtained by pepsin digestion of human IgG from a commercial immunoglobulin preparation for intravenous use or purified from sera of two healthy blood donors and two patients with polyclonal hypergammaglobuinaemia. Isoelectric focusing showed that F(ab′)2 fragments that did not bind PG focused in a lower pH range compared with those which did. Testing of the Fab fractions with MoAbs to κ and λ light chains or to γ1, γ2 and γ3-Fab subclass determinants showed that γ2-F(ab′)2 were mainly found in the PG non-reactive F(ab′)2 fraction, and that this distribution was not influenced by the L chain isotype. These results indicate that the PG-specific binding determinant(s) is not expressed in the F(ab′)2 region of most human IgG2. [ABSTRACT FROM AUTHOR]

Soluble CD4 antigen (sCD4) was measured in seven commercially available intravetious immunoglobulin preparations (IVIg) by means of a double determinant immunoassay (DDIA), whereby two MoAbs recognizing two distinct and spatially distant epitopes on CD4 were used to capture and detect the antigen, respectively. Preincubation of six out of seven IVIg, which were found to be apparently positive for sCD4, with mouse- and bovine-derived serum or purified immunoglobulins completely neutralized DDIA reactivity for sCD4. The inhibition was specific since it was not or only partially observed when IVIg were mixed with whole serum or purified IgG from rabbit. Extensive absorption of six IVIg on insolubilized mouse IgG (mIgG) resulted in a complete loss of reactivity. Eluted human anti-mouse antibodies (HAMA) from any ofthe IVIg displayed a dose-dependent binding in a DDIA, though its extent varied from one preparation to another. Western blot analysis showed that HAMA from all IVIg contained no component with a molecular weight identical with or close to that of recombinant CD4. Purified mIgG markedly influenced the sCD4 reactivity of two IVIg (Sandoglobulin and Globuman I.V.) when sCD4 was measured with a purchased 'CD4-specific Test Kit', thus suggesting that HAMA can exceed the absorbing capacity of the sample diluent. Taken as a whole, these data indicate that sCD4-based DDIA signal is mostly, if not completely, generated by the presence of human immunoglobulin with anti-mouse immunogobulin reactivity, thus casting doubts on the actual occurrence of sCD4 in IVIg. [ABSTRACT FROM AUTHOR]

Patterns of alkaline phosphatase (AP)-binding proteins were observed in the alkaline pH range of 6.5-9.5 upon isoelectric focusing and blotting of serum from patients with inflammatory diseases. After isolation using affinity chromatography on protein A or immunoaffinity chromatography on AP coupled to cyanogen bromide (CNBr)-activated Sepharose, the AP-binding protein was identified as IgG on Western blots and in ELISA using human IgG-specific antibodies. It was shown that this IgG binds to AP from both calf (bovine) and human intestine. However, it binds neither lo the human liver-bone-kidney (LBK) isoform nor to bacterial AP. Moderate reaction was observed with human placental AP. Comparing patients with various diagnoses (n = 284), AP-binding antibodies were mainly found in severe bacterial infections. They were not detected in serum from healthy blood donors (n = 300). The presence of AP-binding IgG was independent of the infected organ and the bacterial species causing infection. This antibody may be useful for discriminating bacterial from viral infection and for indicating severe bacterial inflammation. [ABSTRACT FROM AUTHOR]

Systemic capillary leak syndrome (SCLS) is a rare disease characterized by episodes of collapse due to rapid transfer of considerable volumes of plasma from the intravascular to the extravascular compartment. The pathogenesis of this disease is unknown. The diagnosis is made largely on clinical grounds, and investigations arc unhelpful. The only consistent abnormality is that an IgG paraprotein is found in most patients, raising the possibility that the paraprotein may be involved in the pathogenesis of the disease. Reduction of the paraprotein level in our patient was associated with remission. Blood samples from three SCLS patients and one probable SCLS have been studied. All patients had monoclonal IgG paraproteins. The purified paraproteins were all of IgG1 subclass and had K light chains. However, they differed in size and charge. Antibodies against each of the paraproteins were raised in rabbits. Affinity-purified anti-idiotypic antibodies were tested for cross-reactivity against the other paraproteins using immunoblotting and Ouchterlony assay. These assays showed that the anti-idiotypic antibodies reacted only with the immunizing paraprotein and not with any of the other paraproteins, i.e. that the paraproteins do not share a common idiotype, Paraproteins did not bind to cultured endothelial cells, either unactivated or following activation with interferon-gamma (IFN-γ)- IL-2 or IL-6. In addition, we were unable to demonstrate any cytotoxicity towards cultured human endothelial cells by paraprotein alone, or in the presence of neutrophils (pronounced neutrophilia being a feature of attacks). The relationship between the paraproteins and the disease remains unclear. It is likely that additional, as yet unidentified, factors are required for the paraprotein to lead to capillary leak. [ABSTRACT FROM AUTHOR]

The study of 87 adults of different ages, including 15 centenarians, selected for their healthy status, showed that profound changes of humoral immunity occur throughout life. In particular, a Statistically significant age-related increase of the serum level of immunoglobulin classes (IgG and IgA but not IgM) and IgG subclasses (IgGl, 2 and 3, but not IgG4) was detected. A parallel age related decrease of circulating B cells was also observed. The hypothesis of a complex derangement of B cell function and/or compartmentalization with age is put forward, together with the proposal that healthy centenarians (as representative of successful ageing) may be helpful in identifying the physiological age-related modifications of the immune system. [ABSTRACT FROM AUTHOR]

Twenty-six tgG-secreting and eight IGM-secreting hybridomas were derived from the synovia of two patients with rheumatoid arthritis (RA). Hybridomas were obtained by fusing a heteromyeloma cell line, SPAZ-4 with synovial mononuclear cells that were not deliberately stimulated in vitro. Over 96Y of the EgG-secreting hybridomas produced antibodies which belonged to the IgG1 subclass and showed lambda light chain predominance: the latter was not seen in IgM antibodies. where kappa light chains dominated by 3: 1. All IgG antibodies were cationic. Synovial B cells were not exposed to extrinsic stimuli prior to fusion. therefore these results reflect the state of 13 cell activation and differentiation in vivo. Our results indicate that IgO-secreting B cells in the RA joint arc under a selective influence which is, as yet. unidentified. One out of eight IgM-secreting and two out of 26 IgO-secreting hybridornas produced rheumatoid Factors (RF). The IgM-RF specificity for igO heavy chain subclasses was determined and showed that (he rnonoclonal bound to lgG 1, IgG2 and IgG4 but not lgG3 with exception of IgG3 Goc of the G3m (st) allotype. a profile typical of specificity for the Ga epitope. This monoclonal also distinguished a determinant in the Fe region of human IgG which was flot present in rabbit lgG. The overall frequency of RE-secreting hybridomas we observed indicates that B cells committed to RE production in the cynovium of a seropoitive and a seronegative RA patient is below 10%. [ABSTRACT FROM AUTHOR]

Although cellular immunity has a crucial role during cryptococcosis, several in vitro studies have pointed out the importance of IgG anti Cryptococcus neoformans antibodies and complement components during phagocytosis of the yeast by polymorphonuclear leucocytes and monocytes. We investigated the role of complement and specific antibodies in host defences against experimental cryptococcosis, using a monoclonal IgG1 antibody (E1) specific for cryptococcal capsular polysaccharide, and mice congenitally sufficient or deficient in the fifth component of complement (C5). During in vitro experiments, E1 and the normal mouse serum from C5-sufficient and -deficient mice were unable to inhibit the growth of C. neoformans. However, E1 was an efficient opsonin for the ingestion of C. neoformans by mouse peritoneal macrophages, acting in synergy with normal mouse serum. In vivo, E1 was protective in heavily infected C5-deficient mice (DBA/2) dying from an early acute pneumonia, but not in C5-sufficient mice (BALB/c) and in DBA/2 mice infected with a smaller inoculum dying from a late progressive meningo-encephalitis. Although protection against pneumonia is attributed to a local recruitment of phagocytes in C5-sufficient mice, this was not observed in C5-deficient mice protected with E1. In this case, IgG anti-C. neoformans antibodies seem to be an alternative for an efficient opsonization of the yeasts. Altogether, these data suggest that two main mechanisms may protect infected mice from an early fatal pneumonia: the efficient opsonization of the yeast by complement and the recruitment of phagocytes in infected tissues. [ABSTRACT FROM AUTHOR]

A second major antigen of Aspergillus fumigatus (Ag 13) has been identified and characterized as a 70 kD, heat-labile component which is able to bind to the lectin, concanavalin A, Ag 13 proved to be identical to the previously recognized C antigen, known to possess chymotryptic activity. A monospecific antiserum to Ag 13 has been affinity purified and used to develop a sandwich ELISA for measuring levels of Ag 13 specific IgG antibodies in patients' sera. Although all ABPA sera (25/25) had significantly raised levels, some aspergilloma sera (2/5) had only very low levels; of the control sera. 10/ 10 fungal atopies were negative, but 5/12 farmer's lung sera had low but positive values of Ag 13 specific IgG, i.e. sensitivity 100%, specificity 80%. Ag 13 is therefore a diagnostically important component of A. fumigatus and the antigen-specific ELISA may be of importance for the improved detection of disease-specific antibodies. [ABSTRACT FROM AUTHOR]

Ixodes ricinus-borne borreliosis may run a protracted course. In this study we investigated the different IgG subclasses of antibodies to borreliae at different stages of the disease. In addition to the dominant subclass IgG1 an IgG3 response was found in most cases. This antibody subclass pattern with contributions of IgG2 often persists into the late stage of the disease and may last for decades. The lgG subclass response elicited by this spirochaetosis does not conform to the expected lgG4 restricted response after chronic antigenic stimulation. [ABSTRACT FROM AUTHOR]

Twenty sera from patients with systemic lupus erythematosus (SLE) and high titre of IgG anti-cardiolipin antibodies (ACA) were studied in order to evaluate the prevalence of anti- mitochondrial type 5 antibodies (AMA 5). None of these sera were found to be AMA 5 positive but five of 18 were positive for VDRL. Twenty sera from patients with AMA 5 were studied in order to evaluate the prevalence of ACA: only six of 20 were positive for ACA. In contrast to this finding. 15 of the 20 sera positive for AMA 5 were also positive for VDRL (P<0.001). The six sera positive for ACA and AMA 5 were absorbed with cardiolipin micelles. This absorption eliminated the ACA activity but not the AMA 5 activity. Despite the clinical similarities between the two groups of patients with AMA 5 or ACA. these data suggest that patients with AMA 5 and patients with ACA belong to two different subsets of SLE or SLE-like syndromes and that AMA 5 antigen is different from cardiolipin. [ABSTRACT FROM AUTHOR]

The IgG subclass distribution of anti Rh antibodies (anti-D, "anti-Da'. anti-c, anti-E), anti-Kell and anti-Duffy (anti-Fya) antibodies was measured by two haemagglutination techniques on microtitre plates. The first technique involved rabbit subclass specific antisera which were used to agglutinate red cells previously reacted with the patients' antibodies at high concentration. The second, which was more sensitive, had an additional step by introducing sheep anti-rabbit antibodies (sandwich technique). By the sensitive sandwich technique we revealed, for anti-D antibodies: IgGl 8/19, IgG3 1/19, IgG1/IgG3 8/19, IgGl/lgG2/IgG3/lgG4 1/19, IgG 1/IgG4 1/19; for the Da-reactive anti-D antibodies: IgGl 1/8, IgG1/IgG3 1/8, IgGl/IgG3/IgG4 6/8; for the anti-E antibodies: lgG1/IgG2/ lgG4 2/3,IgGl/IgG2/IgG3/IgG4 1/3: for the anti-c antibodies: IgGl 2/5, IgG3 1/5, IgG 1/ lgG3 1/5: for the anti-Kell antibodies: IgGl 9/20, lgGI/IgG3 1/20, IgGl/IgG4 8/20, IgGl/IgG3/IgG4 2/20; and for anti-Duffy antibodies: IgGl 1/8, IgGl/IgG4 7/8. These results are partly at variance with previously published results. [ABSTRACT FROM AUTHOR]

A prospective study of 146 children was conducted lo evaluate the influence of infant feeding patterns on the development of mucosal immunity. First, there was a trend towards lower IgG concentrations in the breast-fed neonate, indicating a possible earlier "closure" mechanism of membrane permeability. Second, the post-natal increase in IgA was earlier and greater in formula-fed infants. Third. IgM was detected earlier, more frequently, and at higher levels in formula-fed infants. [ABSTRACT FROM AUTHOR]

Combined TgA and IgG2 deficiency is welt recognized as being associated with an increased susceptibility to pyogenic infection. A similar syndrome is described in four patients with IgA deficiency who were unable to produce IgG2 subclass antibodies to pneumococcal capsular polysaccharides but whose total IgG2 levels were in the normal or near normal range. This emphasizes the importance of measuring class and subclass responses to different types of antigen when investigating patients with suspected deficiencies of antibody production. [ABSTRACT FROM AUTHOR]

The IgG response to tetanus toxoid (TT) immunization was quantitated by radioimmunoassay in patients with membranous nephropathy (MN) and healthy controls. Variation in subclass (ELISA) and electrical charge (isoelectric focussing, immunofixation & autoradiography) of the IgG response were also assessed. Total IgG and IgG subclass responses were impaired in MN compared lo controls, although this was only significant for IgG-3 (P < 0.05). Non responders to TT were more common in MN, and response was independent of disease activity. No distinctive pattern of IgG subclass response or IgG spectrotype was seen in MN. Impaired response to TT was associated with HLA-DR3 among controls, and in MN (88.8% of whom were DR3) markedly depressed responses occurred in apparent DR3 homozygotes. [ABSTRACT FROM AUTHOR]

The potential role of thyroid microsomal (Mic) antibodies in the development of postpartum hypothyroidism was investigated in 34 euthyroid women, whose sera were found to contain Mic antibodies in pregnancy. Additional serum Samples were obtained 2, 5 and 10-12 months after delivery and analysed for IgG class and IgG subclass levels of Mic antibodies by ELISA techniques. Characteristically, Mic antibodies decreased from early pregnancy to 2 months postpartum, increased two-fold 5 months postpartum and had returned 10-12 months postpartum to the early pregnancy level. Mic antibodies were predominantly subclass lgG-1 or IgG-4 with only minor contributions from IgG-2 and IgG-3. In each individual the percentage contribution made by each IgG subclass to Mic antibody was essentially similar In early pregnancy and the postpartum period despite changes in total IgG class Mic antibody. During the year following delivery, thyrotoxicosis alone (Graves' disease) developed in 5 women. In the remaining 29 patients the absolute levels of Mic antibodies of IgG-4 subclass were similar 5 months postpartum in women with maximal serum thyrotropin (TSH) >20 mU/1 (mean optical density in ELISA ±s.d.; 0.84±0.538; n=13) and in women with maximal TSH < 10 mU/1 (0.69±0457; n= 16). In contrast, significantly higher values were observed for Mic antibody of IgG-1 subclass in patients with TSH >20 mU/l (1.14 ± 0.440) compared with women with maximal TSH < 10 mU/l (0.65±0.289) (P<0.001 by t-test for groups). These results imply that the magnitude of Mic antibody levels of subclass IgG-1 but not IgG-4 is associated with the development of postpartum hypothyroidism and possibly with tissue destruction in autoimmune thyroid disease in general. [ABSTRACT FROM AUTHOR]

Dogs immunized with o-DNCP-BSA or eggs of Toxocara cans developed anaphylactic antibodies other than IgE. The antibodies were heat-resistant at 56 C for 2 hours, not reduced by 2-mercaptoethanol and PCA and P-K reactivity was only observed at .1-4 h sensitized sites of recipient skin. High titers of antigen-speciRc IgG were determined by means of an ELISA technique. [ABSTRACT FROM AUTHOR]

To determine the inheritance patterns of both IgM class and IgG class hypergammaglobulinaemias, the locations of genes and the relations of these genes to other autoimmune traits in NZB × NZW(B/W) F1 hybrid, we measured serum levels of both IgM and IgG in NZB, NZW, B/W F1 hybrid, B/W F1 × NZW back-cross and B/W F1 × NZB back-cross mice. The highest serum IgM levels were observed in NZB mice, however the serum IgG levels were normal. In contrast, a large amount of IgG was produced in B/W F1 hybrids, in which the serum IgM levels were lower than those observed in NZB mice. The NZW mice had fairly normal values for both measures. Progeny studies suggested that a single dominant locus (Imh-I) of NZB strain, which is loosely linked to brown-black coat colour locus b and Mup-I locus on chromosome 4, determines the IgM class hypergammaglobulinaemia. The estimated gene order was Mup-I:b:Imh:I. This IgM class hypergammaglobulinaemia in NZB mice was suppressed to a considerable extent in B/W F1 hybrid mice by either a gene dosage effect or more likely, a regulatory gene locus of NZW strain, being also loosely linked to Mup-I locus on chromosome 4. As for the IgG class hypergammaglobulinaemia, a complementary effect of two or three genes, either one or two dominant genes derived from NZB and a single dominant gene from NZW strains, determines this trait in B/W F1 hybrid mice. There appeared to be no relationships between the genes responsible for the IgM class and IgG class hypergammaglobulinaemias. When looking at the correlations between the hypergammaglobulinaemias and the traits, anti-double stranded DNA (dsDNA) antibodies and renal disease in both back-cross mice, we found a significant quantitative correlation only between the IgG class hypergammaglobulinaemia and the IgG class anti-dsDNA antibodies in B/W F1 × NZB back-cross mice. [ABSTRACT FROM AUTHOR]

Helminth parasites induce production of high levels of IgE antibodies but the immunoregulatory mechanisms determining this IgE biosynthesis are poorly understood. To investigate these mechanisms, peripheral blood mononuclear cells were obtained from six normal controls, six atopic patients and eight patients with parasitic helminth infections (three with schistosomiasis, two with loiasis. three with onchocerciasis). Cells were cultured at 1 × 106 cells/ml for 8 days in the presence of media alone or media supplemented with pokeweed mitogen (PWM) or cycloheximide; the supernatant fluids from these cultures were then assayed quantitatively for total and parasite specific IgE and IgG using an avidin-biotin amplified (for IgE) or standard (for IgG) microelisa assay. The geometric mean spontaneous IgE production was markedly elevated in peripheral blood mononuclear cells from parasitized individuals (2,487 pg/ml) when compared to those from atopics (358 pg/ml) or normals (152 pg/ml). Spontaneous IgG synthesis was equivalent in all three groups (range 140-420 ng/ml). PWM did not induce IgE production in any group and in the parasitized group even caused significant suppression of total IgE synthesis. Antigen specific antibody production (both IgE and IgG) paralleled total immunoglobulin synthesis. These findings demonstrate for the first time spontaneously enhanced IgE production in vitro in patients with helminth infections and provide a model system for studying the suppressive and regulatory mechanisms controlling IgE secretion. [ABSTRACT FROM AUTHOR]

IgG subclasses of antibodies to rubella were determined in indirect enzyme linked immunoassay (ELISA) with monoclonal antibodies specific for human IgG1, IgG2, IgG3 and IgG4. Eleven sera from women with long past history of rubella, two hyperimmune and five non-hyperimmune immunoglobulin preparations were tested. Light chain types of the antibodies were tested in ELISA with polyclonal specific antibodies to kappa and lambda chains. Antibodies to rubella in the sera as well as in the immunoglobulin preparations were found in the IgG1 subclass only. Both light chain types were present in the antibodies. [ABSTRACT FROM AUTHOR]

Heat aggregated IgG and soluble immune complexes (IC) prepared by combining human serum albumin with rabbit anti-serum albumin and tetanus toxoid with rabbit antiserum to tetanus toxoid were shown to bind to human O+ RBC. The binding was greater for soluble IC prepared at antigen excess, and although it was usually maximal when IC were pre-opsonized, it could also be demonstrated using non-opsonized heat aggregated IgG or soluble IC prepared in the absence of complement. These observations suggest that two types of receptors may be involved in binding of soluble IC to human RBC: the classical C3b receptor, and a non-complement-dependent receptor, perhaps recognizing the Fc region of the immunoglobulin molecule exposed after heat aggregation or antigen-antibody reaction. [ABSTRACT FROM AUTHOR]

The properties of five monoclonal antibodies (McAbs) which react with free κ chains but not with IgGκ. IgMκ or IgAκ have been studied. IgG preparations stored for long periods sometimes contained low and high molecular weight material reacting as free κ. This could be removed by passing the preparation through an affinity column to which two of the McAbs had been coupled, but reactive material reappeared when the purified IgG was heated at 65°C. Two of the McAbs from one fusion reacted with F(ab')2 fragments of IgG whereas two from another fusion did not. Pairs of McAbs (one from each fusion) were much more sensitive in the detection of free κ. particularly monomer, than a single McAb. This provided the basis for a very sensitive method of detection of free κ chains in human body fluids and culture supernales. [ABSTRACT FROM AUTHOR]

The effect of IgE soluble immune complex (SIC) and IgG SIC on neutrophil chemotaxis was investigated. Eight types of SIC were prepared from κ type IgE myeloma protein and lgG myeloma protein: IgE-anti-κ SIC in IgE excess and in anti-κ excess. IgE anti-∊ SIC in IgE excess and in anti-∊ excess, IgG-anti-κ SIC in lgG excess and in anti-k excess. IgG-anti-γ SIC in IgG excess and in anti-γ excess. Four types of IgE SIC markedly suppressed neutrophil and chemotaxis, but free IgE, free anti-κ chain antibody. Free anti-∊ chain antibody and IgG SIC had no inhibitory activity. This inhibitory activity of lgE SIC on neutrophil chemotaxis was cell directed and concentration-dependent. IgE immune complex also inhibited neutrophil chemotaxis when immune complex was formed in the neutrophil chemotaxis. [ABSTRACT FROM AUTHOR]

The antigenic specificities of RNA reactive IgG autoantibodies from three individual human SLE sera and pooled NZB/NZW mouse serum were studied by competition reactions with synthetic co-polymers and heteropolymers of varying nucleotide compositions. Although minor differences in the individual binding patterns were noted, the RNA reactive immunoglobulins showed a clear preference for G. C" and G,C,U containing RNA sequences. All three SLE sera had Sm or RNP activities with rabbit thymus extractable nuclear antigen (ENA). Conversely, all SLE sera that were selected on the basis of their positive ENA reaction could also bind free, single stranded RNA. These results suggest that the autoimmune response to RNA in human and murine SLE is restricted to one or a very few antigenic determinants. They also raise the possibility that autoantibodies to native RNA in SLE sera are partly responsible for ENA reactivity. [ABSTRACT FROM AUTHOR]

An efficient and reproducible procedure has been developed for the specific isolation of immune complexes. PEG precipitation of EDTA serum or plasma was an essential preliminary step to separate complex-bound from free Clq. PEG had no discernible effect on the molecular weight size of the extracted complexes. Redissolved complexes were incubated with a Sepharose-4B column coated with anti-human Clq antibodies and following removal of unbound material the bound complexes were sequentially eluted with 0.02 M EDTA, 0.5 M NaCl and 1 M propionic acid. Characteristics of the affinity column were established by the purification of 125I-labelled BSA-anti-BSA complexes and heat-aggregated IgG (HAGG) incubated in normal human scrum (NHS), EDTA and NaCl eluted complexes were of similar molecular size and contained antigen, specific antibody, as well as human IgM, IgG, albumin, C3, C3c, C3d and Clq. Acid eluted complexes contained the highest yield of specific antigen and antibody and comprised in addition human Clq and C3d. Activation of complement components after Clq made the bond between Clq and immune complexes resistant to 0.5 M NaCl and interfered with the binding between solid phase anti-Clq and complex bound Clq. Using BSA-anti-BSA complexes and HAGG activated in NHS it was apparent that only a minority of the complexed material was isolated via the Clq ligand and this probably applies to the Clq binding assay. Most complexed material could be isolated using an anti-C3 affinity column. [ABSTRACT FROM AUTHOR]

The presence of surface-associated immunoglobulins and Fc receptors on mononuclear cells from normal human blood was investigated by the direct immunofluorescence technique combined with phase-contrast microscopy. Formaldehyde-fixed cells were compared to unfixed cells and to cells preincubated at 37 C. In the unfixed samples a separate population which showed Fc receptors in an immunofluorescence technique using a labelled antigen-antibody complex was detected. This cell population showed an atypical, i.e. not clearly membrane-associated, pattern of fluorescence with anti-Fab conjugates. This interaction most probably is due to autologous IgG molecules taken up by these cells from the donor serum. Using phase-contrast microscopy, these cells were morphologically distinct from lymphocytes and mature monocytes. They will be referred to as "undefined mononuclear cells" (UMC). After formaldehyde fixation or preincubation at 37°C the interaction of the UMC with anti-Fab conjugates could no longer be demonstrated. Mature monocytes show the same atypical fluorescence pattern with anti-Fab conjugates, but in contrast to the UMC the interaction persists after formaldehyde fixation or preincubation at 37°C. No evidence was found for passive uptake of labelled IgG from conjugates by any mononuclear cell. F(ab')2 fragments of IgG from antisera gave results similar to those obtained with intact IgG fractions. The morphology of the different cell subpopulations is described and their relative numbers in normal blood are given. Formaldehyde fixation proved to be a simple and useful procedure, especially for the determination of the number of B lymphocytes, because the Fc receptor of the undefined mononuclear cells does not give rise to confusion. [ABSTRACT FROM AUTHOR]

The IgG subclass and Gm allotype distribution of red cell-bound IgG molecules from Gambian children with past or present falciparum malaria has been determined. The results show that the antibody is polyclonal with some predominance of the IgG2 and IgG4 subclasses. A restriction towards IgG2 antibodies may indicate specificity for a schizont-derived antigen which is carbohydrate in nature. Not all the allotypes normally carried by the G3m(b) allele could be demonstrated on IgG3-sensitized cells, a finding which remains unexplained. Expression of G3m(10), (11) and (14) allotypes of the IgG3 molecule was noted. Sensitization of red cells with IgG1 molecules correlated with the presence of anaemia but red cells sensitized with IgG2, IgG3 or IgG4 usually came from children with haematological findings within the normal range for that population. The implications of the results are discussed with reference to the few reports on the subclass and Gm allotype of malaria-specific IgG. [ABSTRACT FROM AUTHOR]

The effect of procarbazine and cyclophosphamide on the formation of antibodies to sheep red blood cells in mice is investigated. Cyclophosphamide was found to have the best immunosuppressive effect when given after antigen; recovery from drug treatment was relatively fast; under experimental conditions that favour cyclophosphamide action (antigen prior to drug) IgM formation was found to be depressed and prolonged; IgG formation was markedly depressed or altogether missing. Procarbazine was found to act best when given prior to antigen; recovery was slow; under experimental conditions that favour procarbazine action (drug prior to antigen) the induction period was prolonged. IgM titres were slightly and IgG titres markedly depressed. Under all conditions tested procarbazine had little effect on the onset of IgG production. [ABSTRACT FROM AUTHOR]

Antibodies in human sera against four different antigens of human spermatozoa discovered by means of an indirect two-layer immunofluorescence technique (IFT) were characterized by determination of the class of immunoglobulins to which they belonged. A three-layer IFT using monospecific antisera against human IgG, IgA or IgM as the second layer was employed together with fractionation of sera on Sephadex G-200 or DEAE-cellulose followed by testing of the concentrated pools in a two-layer IFT. The study revealed that antibodies against the antigen in the front part of the acrosome were primarily IgM and those against the antigen in the tail primarily IgG. Antibodies against antigens in the equatorial segment and the postnuclear cap showed a varying predominance of these two immunoglobulins. Spermatozoal antibody as IgA was found only in small amounts. [ABSTRACT FROM AUTHOR]

Polyclonal Ig of one or other class was significantly reduced in 82% of subjects with monoclonal protein disease (MPD). Ig deficiency was equally frequent with all classes of monoclonal Ig, but was considerably more common in myelomatosis than in benign MPD. Polyclonal IgG isolated from sera containing monoclonal IgG, IgA or IgM was normal in regard to electrophoretic heterogeneity and proportions of κ- and γ-chains. Peripheral lymphoid. tissues from most patients within deficiency failed to synthesize the corresponding polyclonal Ig in vitro. Monoclonal protein was synthesized by macroglobulinaemic lymph node tissue, but monoclonal proteins were riot synthesized by nodes from subjects with, myelomatosis. Polyclonal Ig deficiency in macroglobulinaemia can be ascribed to peripheral spread of neoplastic cells, but the same process does not apparently account for Ig deficiency in typical cases of myelomatosis. [ABSTRACT FROM AUTHOR]

The nature of the heat precipitation of 3 mononoclonal heat labile immunoglobulins was studied. These included 2 γG pyroglobulins and one γM pyroglobulin. Thermoprecipitable activity of both γ3 pyroglobulins could be localized to their heavy chains and to the Fab fragments of one of them. Heat precipitability of the γM paraprotein required the presence of the intact γM molecule since 7S subunits did not precipitate. The thermal precipitates appeared to result from intramolecular or intermolecular reactions with the formation of strong covalent bonds rather than weak non-covalent bonds. The importance of disulphide bonding was excluded in the precipitation of both γG but not in the γM pyroglobulins. Heat precipitation of the monoclonal γM resulted in coprecipitation of other proteins, particularly γG globulin, which suggested a specific type of reaction with this immunoglobulin. The Interaction of the γM pyroglobulin, normal γG and heat produced an irreversible precipitate. [ABSTRACT FROM AUTHOR]

IgG, IgA, IgM and IgD concentrations in plasma were measured at three surveys of a rural Gambian community made over 13 months. 3523 samples were analysed. The pattern of change with age of mean levels of each immunoglobulin class was similar at each survey, although IgM levels were highest in the survey made at the end of the wet season. immunogiobulin levels in the same individual were found to be relatively stable in adults over the study period. Only minor correlations were found between the levels of different immunogiobulin classes in plasma from the same individual. Malarial parasitaemia was associated with increased mean IgG levels in age groups up to 20 years but with increased IgM levels only in the first 2 years of life. Plasma which contained precipitating antibodies to malarial antigens showed higher mean levels of IgG and IgM in most age groups. In association with splenomegaly mean IgG levels were increased throughout childhood while mean IgM levels were elevated only in the first 2 years. No consistent relationship between malaria and mean levels of IgA and IgD were noted. The only relationship found between haemoglobin concentration and immunoglobulin levels was a small negative correlation in respect of IgM. Clinical infection, other than malaria, was associated with increased mean levels of IgG and IgA in all age groups and of IgM in young children. Lower levels of IgG, IgA and IgM occurred in pregnancy; IgG levels seemed to fall progressively as pregnancy advanced. At certain ages mean levels of IgM and IgD were higher in females than males. [ABSTRACT FROM AUTHOR]

The electrophoretic distribution of Kappa and Lambda light chain antigenic determinants were studied in cerebrospinal fluid (CSF) and serum from cases with abnormal immunoglobulin G patterns on agar gel electrophoresis of CSF. Electrophoretically homogeneous immunoglobulin fractions containing an excess of either Kappa or Lambda determinants were found in CSF but not in serums. The findings indicate the production of monoclonal immunoglobulins within the central nervous system in multiple sclerosis. [ABSTRACT FROM AUTHOR]

By immunizing rabbits with immune precipitates containing autologous IgG as the antibody parts, most animals produced both rheumatoid factor-like antibodies and antibodies to human and rabbit F(ab')2 lgG. The latter antibodies resembled the human antibodies to the pepsin site of lgG by not reacting with untreated IgG and by reacting with immune precipitates made From autologous and homologous antibodies. The rabbit antibodies to the pepsin site of IgG in most cases consisted of a mixture of IgG and IgM, while the human antibody is usually pure IgG. The investigation demonstrated that in addition to rheumatoid factor, other human anti-lgG antibodies may also be due to antigenic stimulation by autologous IgG in immune complexes. [ABSTRACT FROM AUTHOR]

A new method was used to measure immunoglobulin and total Protein concentrations in nasal secretions of normal infants and infants with acute respiratory infections and with allergies. A measured quantity of inulin was added to the administered wash solution in order to determine the dilution of the nasal secretions washed from the infants, in normal infants IgA concentration was less than IgG concentration. In nasal secretions from infants with acute respiratory infections IgA concentration was higher and IgG concentration was lower than in secretions from normal infants. Nasal secretions were studied without the inulin marker in a larger group of normal infants arid in infants with acute respiratory infections, a family history of asthma, atopic dermatitis or asthma. Only relative concentrations of immunoglobulins and total protein can be determined from these studies. There was no difference between the group with a family history of asthma and the control group. IgA/IgG and IgG/TP ratios in asthmatics were not significantly different from those in normal subjects. IgG/TP was significantly lower in asthmatics than in normal infants. Infants with atopic dermatitis had a lower IgA/IgG ratio in their secretions than normal nonallergic controls. The possible implications of these findings to the development of the immune system and the pathogenesis of disease are discussed. [ABSTRACT FROM AUTHOR]

Anti-lymphocytic IgG (ALG) in moderate doses postponed the onset of spontaneous renal disease in (NZB × NZW)F1 hybrid (BW) mice decreasing their mortality. This result only occurred if antibody formation to the ALG was prevented by first rendering the mice tolerant to normal rabbit IgG (NRG), otherwise acceleration of renal disease occurred. This acceleration was particularly marked if γ-globulin, rather than a purified IgG preparation of ALG were used and was further enhanced by adult thymectomy. The development of antinuclear antibody was not delayed by ALG nor was the rise in the serum IgM levels. The effects of ALG are seriously modified by alterations in factors such as dosage used. preceding tolerance to the NRC, thymectomy and strain of mouse used [ABSTRACT FROM AUTHOR]

The 24-hr urinary excretion and clearances of IgA, IgG, siderophilin and albumin have been determined on specimens from twenty-one hospital patients, nine of whom had urinary tract infection. Patients with normal creatinine clearance and urinary tract infection had significantly increased urinary excretion and clearances of all four proteins, compared to patients with normal creatinine clearance and no urinary tract infection. IgM was found in the urine of five patients with urinary tract infection, and in three of these IgD was also present. There was no evidence that the presence of IgM and IgD in the urine of these patients was a direct result of infection. [ABSTRACT FROM AUTHOR]

The article presents information on Ig-allotype-anti-Ig-allotype reaction in rabbit skin. In rabbits, immunized against allotype specificities local dermal reactions were produced by intradermal injections of the appropriate allotype antigen. The reactions were characterized by redness of the skin, infiltration and oedema. The reactions initially appeared about 24 hr after the intradermal injections. The present study shows that small amounts of allotypic antigen injected intradermally into rabbits immunized with the antigen in question produce local reactions characterized by redness of the skin, oedema and infiltration. The dermal reactions that could be produced after five or seven subcutaneous immunizations appeared about 24 hr after the injection.