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As the amount of biomedical information available in the literature continues to increase, databases that aggregate this information continue to grow in importance and scope. The population of databases can occur either through fully automated text mining approaches or through manual curation by human subject experts. We here report our experiences in populating the National Institute of Allergy and Infectious Diseases sponsored Immune Epitope Database and Analysis Resource ( IEDB, http://iedb.org), which was created in 2003, and as of 2012 captures the epitope information from approximately 99% of all papers published to date that describe immune epitopes (with the exception of cancer and HIV data). This was achieved using a hybrid model based on automated document categorization and extensive human expert involvement. This task required automated scanning of over 22 million PubMed abstracts followed by classification and curation of over 13 000 references, including over 7000 infectious disease-related manuscripts, over 1000 allergy-related manuscripts, roughly 4000 related to autoimmunity, and 1000 transplant/alloantigen-related manuscripts. The IEDB curation involves an unprecedented level of detail, capturing for each paper the actual experiments performed for each different epitope structure. Key to enabling this process was the extensive use of ontologies to ensure rigorous and consistent data representation as well as interoperability with other bioinformatics resources, including the Protein Data Bank, Chemical Entities of Biological Interest, and the NIAID Bioinformatics Resource Centers. A growing fraction of the IEDB data derives from direct submissions by research groups engaged in epitope discovery, and is being facilitated by the implementation of novel data submission tools. The present explosion of information contained in biological databases demands effective query and display capabilities to optimize the user experience. Accordingly, the development of original ways to query the database, on the basis of ontologically driven hierarchical trees, and display of epitope data in aggregate in a biologically intuitive yet rigorous fashion is now at the forefront of the IEDB efforts. We also highlight advances made in the realm of epitope analysis and predictive tools available in the IEDB. [ABSTRACT FROM AUTHOR]

Summary: Some human antibodies may paradoxically inhibit complement activation on bacteria and enhance pathogen survival in humans. This property was also claimed for IgG antibodies reacting with terminal galactose‐α‐1,3‐galactose (Galα3Gal; IgG anti‐αGal), a naturally occurring and abundant antibody in human plasma that targets numerous different pathogens. To reinvestigate these effects, we used IgG anti‐αGal affinity isolated from a pool of normal human IgG and human hypogammaglobulinaemia serum as a complement source. Flow cytometry was performed to examine antibody binding and complement deposition on pig erythrocytes, Escherichia coli O86 and Streptococcus pneumoniae serotype 9V. Specific nanobodies were used to block the effect of single complement factors and to delineate the complement pathways involved. IgG anti‐αGal was capable of activating the classical complement pathway on all the tested target cells. The degree of activation was exponentially related to the density of bound antibody on E. coli O86 and pig erythrocytes, but more linearly on S. pneumoniae 9V. The alternative pathway of complement amplified complement deposition. Deposited C3 fragments covered the activating IgG anti‐αGal, obstructing its detection and highlighting this as a likely general caveat in studies of antibody density and complement deposition. The inherent capacity for complement activation by the purified carbohydrate reactive IgG anti‐αGal was similar to that of normal human IgG. We propose that the previously reported complement inhibition by IgG anti‐αGal relates to suboptimal assay configurations, in contrast to the complement activating property of the antibodies demonstrated in this paper. [ABSTRACT FROM AUTHOR]

The article presents an announcement inviting physicians and researchers to submit papers on subjects like "Methods for the Early Diagnosis of Genetic Disorders," 1977, which is an original research paper on "Molecular Biology of Metabolic Diseases." Manuscripts shall not exceed twenty typewritten pages, including illustrations, tables bibliography. Manuscripts marked "Competition," must reach the publishers, S. Karger AG. The winning papers will be published in English in one of the Karger journals.

Human leucocyte lysosomal polypeptides of mol. wt 4000-5000, which constitute the neutrophil-immobilizing factor (NIF), were isolated from the 22,000 g supernate of sonicates of human neutrophils by filtration on Sephadex G-75. The larger (NIF-1) and smaller (NIF-2) of the polypeptides were resolved by filtration on Bio-Gel P6 and purified to homogeneity by sequential reverse-phase high performance liquid chromatography and paper electrophoresis. The results of analyses of amino acid composition indicated that NIF-1 and NIF-2 are distinct polypeptides composed of an apparent total of 41 and 38 amino acids, respectively. Both NIF polypeptides contain one cysteine and one methionine, lack isoleucine, tyrosine and phenylalanine, and are rich in histidine and praline. The sequence of 20 of the amino-terminal amino acids of both NIF polypeptides is identical, but NIF-2 possesses an additional alanine at the amino-terminus. Highly purified NIF-1 and NIF-2 inhibited human neutrophil random migration and chemotaxis to diverse stimuli in a concentration-dependent manner, with 50% inhibition of chemotaxis by 0.3-1 &times 10-8 M NIF-1 and 1-3 × 10-7 M NIF-2. Neither NIF polypeptide was cytotoxic for neutrophils, altered neutrophil phagocytosis or release of lysosomal enzymes, or inhibited mononuclear leucocyte chemotaxis. The leucocyte and functional specificity of the NIF polypeptides and the quantities released upon stimulation of human leucocytes suggest that the transition to a mononuclear leucocyte population in chronic inflammation may be attributable in part to the NIF thrived from the leucocyte infiltrates of acute responses. [ABSTRACT FROM AUTHOR]

Ammonium sulphate precipitation and DEAE chromatography is an efficient way of purifying Ag 11, the main allergen in Dermatophagoïdes farinae mites, which has already been characterized by crossed radioimmunoelectrophoresis. At 60% of saturation in ammonium sulphate, a precipitate is formed which, dissolved and dialysed has been named fraction A 60. It is mainly composed of Ag 11. In the fraction DE obtained by DEAE chromatography of the ammonium sulphate fraction A 60, Ag 11 appears homogeneous on crossed-immunoelectrophoresis. Isoelectrofocusing results indicate an average isoelectric point near neutrality in agreement with the non-absorbtion of Ag 11 on the DEAE cellulose at a weak ionic strength (0.01, at pH 7.2). By sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and gel filtration Ag 11 has a molecular weight of 28,000. Ag 11 appears as a single polypeptidic chain with numerous dithio-bonds implying a highly folded and resistant structure. Oligosaccharides could be present as constituting molecules as well as contaminating ones as was assumed for henosamines. These results are discussed with reference to a similar study performed on the major allergen of Dermatophagoïtes pteronyssinus. The allergenic properties of Ag 11 as present in fraction DE were tested by RAST-based methods. Fraction DE is an inhibitor as good as Df 80d and when it is coated on paper discs it can bind specific IgE in sera from the majority of mite sensitive patients. The results suggest that Ag 11 is a major allergen from D. farinae. [ABSTRACT FROM AUTHOR]

The first paper in this series reported that it was possible to reconstitute the response of low concentrations of mouse spleen lymphocytes to concanavalin A (Con A) by adding small numbers of peritoneal exudate cells (PEC) to the cultures. In this paper it is shown that the role of the PEC in this system can be partially replaced by conditioned medium (CM) prepared from PEC cultures or completely replaced by CM taken from lymphocytes cultured at optimal concentration. These CM were inactive unless fresh Con A was added to the assay cultures. Activity was present in CM which was incubated with lymphocytes or PEC for the shortest possible time but maximal activity was found after 24 hr of incubation. Activity was also found in CM prepared in the absence of Con A. Only in the case of lymphocytes cultured at optimal concentration for 24 hr was there substantially more activity in the CM thus prepared if Con A was present. PEC preparations depleted of T lymphocytes produced as much activity in CM as the untreated control. CM produced by PEC was less sensitive to heat treatment or to freezing and thawing than that produced by lymphocyte cultures. [ABSTRACT FROM AUTHOR]

In the preceding paper a population of lymphoid cells was identified which (1) were derived from germinal centres in the appendix, (2) were localized in follicular structures elsewhere, and (3) could perform as antibody-forming cell precursors. The present paper presents evidence (1) that germinal centres in the spleen and lymph nodes perform the same function as germinal centres in the appendix, and (2) that germinal centres are dependent upon a stream of cells derived from the bone marrow. A new hypothesis is put forward regarding the origin and cellular kinetics of the B-cell system in mammals. It is proposed that germinal centres throughout the body function as an essentially antigen-dependent amplification system for the B-cell population of lymphocytes. Implications of this hypothesis are discussed. [ABSTRACT FROM AUTHOR]

Immunofluorescent and isotope coprecipitation techniques provided methods of studying in vitro production of antibody by chicken spleen cells. In some culture preparations precipitating antibody was produced in sufficient quantity to be measured by quantitative techniques. The in vitro production of globulins by chicken spleen cells has been demonstrated by paper and immunoelectrophoresis of tissue culture medium. The antibody in the globulin produced in the in vitro tissue culture preparations may be shown by an autoradiograph of the immunoelectrophoresis after the addition of antigen trace labelled with radioactive iodine. [ABSTRACT FROM AUTHOR]

Summary: The study of cellular and molecular immunology is almost completely dependent on monoclonal antibody technology. Despite the relatively long history of monoclonal antibodies, there is still huge potential for developing novel and transformative uses for this technology. In this issue of Immunology, we present two such papers, one focussing on anti‐complement (C5) antibodies, the other on anti‐CD6‐specific antibodies. Both manuscripts describe novel ways that monoclonal antibodies may be used for scientific and potentially for therapeutic benefit. [ABSTRACT FROM AUTHOR]

Myeloid-derived suppressor cells (MDSC) are important to the tumour microenvironment as they actively suppress the immune system and promote tumour progression and metastasis. These cells block T-cell activation in the tumour microenvironment, preventing anti-tumour immune activity. The ability of a treatment to alter the suppressive function of these cells and promote an immune response is essential to enhancing overall therapeutic efficacy. Interleukin-12 (IL-12) has the potential not only to promote anti-tumour immune responses but also to block the activity of cells capable of immune suppression. This paper identifies a novel role for IL-12 as a modulator of MDSC activity, with implications for IL-12 as a therapeutic agent. Treatment with IL-12 was found to alter the suppressive function of MDSC by fundamentally altering the cells. Interleukin-12-treated MDSC exhibited up-regulation of surface markers indicative of mature cells as well as decreases in nitric oxide synthase and interferon-γ mRNA both in vitro and in vivo. Treatment with IL-12 was also found to have significant therapeutic benefit by decreasing the percentage of MDSC in the tumour microenvironment and increasing the percentage of active CD8 T cells. Treatment with IL-12 resulted in an increase in overall survival accompanied by a reduction in metastasis. The findings in this paper identify IL-12 as a modulator of immune suppression with significant potential as a therapeutic agent for metastatic breast cancer. [ABSTRACT FROM AUTHOR]

In the early 1970s a spate of papers by research groups around the world provided evidence for a negative regulatory role of thymus-derived lymphocytes (T cells). In 1971, Gershon and Kondo published a seminal paper in Immunology entitled ‘Infectious Immunological Tolerance’ 1 indicating that such negative regulation could be a dominant effect that prevented otherwise ‘helpful’ T cells from mediating their function. Over the next decade, suppressor T cells, as these negative regulatory cells became known, were intensively investigated and a complex set of interacting cells and soluble factors were described as mediators in this process of immune regulation. In the early 1980s, however, biochemical and molecular experiments raised questions about the interpretation of the earlier studies, and within a few years, the term ‘suppressor T cell’ had all but disappeared from prominence and research on this phenomenon was held in poor esteem. While this was happening, new studies appeared suggesting that a subset of T cells played a critical role in preventing autoimmunity. These T cells, eventually dubbed ‘regulatory T cells’, have become a major focus of modern cellular immunological investigation, with a predominance that perhaps eclipses even that seen in the earlier period of suppressor T cell ascendancy. This brief review summarizes the rise and fall of ‘suppressorology’ and the possibility that Tregs are a modern rediscovery of suppressor T cells made convincing by more robust models for their study and better reagents for their identification and analysis. [ABSTRACT FROM AUTHOR]

Summary: The concept of trained immunity refers to remodelling of the monocyte and macrophage metabolic and epigenetic landscape, conferring an amplified inflammatory response upon secondary stimulation. This effect is typically modelled in vitro by stimulating monocytes with either Bacillus Calmette Guerin (BCG) or β‐Glucan for 24 hr, before subsequent stimulation with LPS or Pam‐3‐Cys (P3C) as a secondary stimulus 6 days later. Here, we focus on a recent paper which interrogated the role of the anti‐inflammatory TLR, TLR10, on trained immunity. Using both an in vitro model of trained immunity, and analysis of BCG vaccinated individuals, the authors interestingly demonstrate that, despite its ability to regulate aspects of innate immunity, TLR10 does not have a significant role in this process. [ABSTRACT FROM AUTHOR]

Nik is a classically trained immunologist in the field of T-cell activation and memory, and has also become something of an engineer in preclinical mouse models. This month, I'll be kicking off a series of editorials written based on more or less casual conversations I've had with some emerging leaders in the field of immunology. I I think the excitement over the immunology of cancer and its microenvironment has helped catalyse the transition to understanding immunity in at least that transformed tissue. [Extracted from the article]

MHC class I-related gene protein (MR1) is a non-polymorphic MHC class IB antigen-presenting molecule that is the restricting molecule for mucosal-associated invariant T (MAIT) cells, a prominent population of innate-like antibacterial T cells. The MAIT cell-MR1 axis represents a new paradigm in antigen presentation, with the MR1 ligand derived from vitamin B compounds or their metabolic precursors. Many bacteria and some fungi produce the activating ligand for MR1. In evolution, MR1 is highly conserved in most, but not all, mammals. In humans and rodents it is expressed in a broad range of cell types, both haematopoietic and non-haematopoietic, although cell surface expression has been difficult to detect. Although MR1 trafficking shares features with both the MHC class I and MHC class II pathways, it is distinct. Several strands of evidence suggest that the intracellular location where MR1 is loaded differs for soluble ligand and for ligand derived from intact bacteria. The regulation of MR1 surface expression may also vary between different cell types. This paper will review what is currently known about the expression and trafficking of MR1 and propose a model for the loading and trafficking of MR1. [ABSTRACT FROM AUTHOR]

The nuclear factor- κB (NF- κB) family of transcription factors play an essential role for the regulation of inflammatory responses, immune function and malignant transformation. Aberrant activity of this signalling pathway may lead to inflammation, autoimmune diseases and oncogenesis. Over the last two decades great progress has been made in the understanding of NF- κB activation and how the response is counteracted for maintaining tissue homeostasis. Therapeutic targeting of this pathway has largely remained ineffective due to the widespread role of this vital pathway and the lack of specificity of the therapies currently available. Besides regulatory proteins and microRNAs, long non-coding RNA (lncRNA) is emerging as another critical layer of the intricate modulatory architecture for the control of the NF- κB signalling circuit. In this paper we focus on recent progress concerning lncRNA-mediated modulation of the NF- κB pathway, and evaluate the potential therapeutic uses and challenges of using lncRNAs that regulate NF- κB activity. [ABSTRACT FROM AUTHOR]

The antigenic reactivity of constituents of Schistosoma mansoni and peanut ( Arachis hypogaea) was investigated to determine whether identical antigenic epitopes possessed by both organisms provided a possible explanation for the negative correlation between chronic schistosome infection and atopy to allergens. Aqueous extracts of peanuts were probed in Western immunoblots with rabbit IgG antibodies raised against the egg, cercarial and adult worm stages of S. mansoni. Several molecules in the peanut extract were antigenically reactive with antibodies from the various rabbit anti-schistosome sera. A pair of cross-reactive peanut molecules at ~30 000-33 000 molecular weight was purified and both proteins were identified by mass spectrometric analysis as the peanut allergen Ara h 1. Anti- S. mansoni soluble egg antigen antibodies that were eluted off the peanut molecules reacted with two S. mansoni egg antigens identified by mass spectrometry as IPSE/ α-1 and κ-5. Alignments of the amino acid sequences of Ara h 1 and either IPSE/ α-1 or κ-5 revealed a low level of peptide sequence identity. Incubation of nitrocellulose paper carrying electrophoresed peanut molecules, six constituents of other allergic plants and S. mansoni egg antigens in a mild solution of sodium metaperiodate before probing with antibodies, inhibited most of the cross-reactivities. The results are consistent with the antigenic cross-reactive epitopes of S. mansoni egg antigens, peanut and other allergic plants being cross-reactive carbohydrate determinants (CCDs). These findings are novel and an explanation based on 'blocking antibodies' could provide an insight for the inverse relationship observed between schistosome infection and allergies. [ABSTRACT FROM AUTHOR]

B cells have an important pathogenic role in the development of type 1 diabetes in the non-obese diabetic ( NOD) mouse. We have previously reported that NOD mice display an increased percentage of TACIhigh-expressing B cells compared with C57 BL/6 mice and this trait is linked to chromosomes 1 and 8. In this paper the genetic association of the transmembrane activator, calcium modulator and cyclophilin ligand interactor ( TACI) trait was confirmed using double congenic NOD. B6C1/Idd22 mice. TACI ligation by a proliferation-inducing ligand ( APRIL) has been shown to influence plasma cell differentiation, immunoglobulin production and isotype switch. Hence, the functional consequence of the up-regulation of TACI on NOD B cells was analysed both in vitro and in vivo. NOD B cells stimulated with APRIL showed an enhanced plasma cell differentiation and class switch to IgG and IgA compared with B cells from C57 BL/6 mice. Moreover, flow cytometry analyses revealed that germinal centre B cells in NOD failed to down-regulate TACI. Availability of the TACI ligand B-cell activating factor ( BAFF) has been shown to be a limiting factor in the germinal centre reaction. In line with this, upon immunization with 4-hydroxy-3-nitrophenylacetyl hapten-conjugated hen egg lysozyme, NOD mice produced higher titres of low-affinity antibodies compared with C57 BL/6 mice. This observation was supported by the detection of increased levels of BAFF in NOD germinal centres after immunization compared with C57 BL/6 by immunofluorescence. Our results support the hypothesis that increased TACI expression on NOD B cells contributes to the pathogenesis of type 1 diabetes in the NOD mouse. [ABSTRACT FROM AUTHOR]

Summary: There have been substantial strides forward in our understanding of the contribution of regulatory T (Treg) cells to cancer immunosuppression. In this issue, we present a series of papers highlighting emerging themes on this topic relevant not only to our understanding of the fundamental biology of tumour immunosuppression but also to the design of new immunotherapeutic approaches. The substantially shared biology of CD4+ conventional T (Tconv) and Treg cells necessitates a detailed understanding of the potentially opposing functional consequences that immunotherapies will have on Treg and Tconv cells, a prominent example being the potential for Treg‐mediated hyperprogressive disease following anti‐PD‐1 therapy. Such understanding will aid patient stratification and the rational design of combination therapies. It is also becoming clear, however, that Treg cells within tumours exhibit distinct biological features to both Tconv cells and Treg cells in other tissues. These distinct features provide the opportunity for development of targeted immunotherapies with greater efficacy and reduced potential for inducing systemic toxicity. [ABSTRACT FROM AUTHOR]

Examines the technique for immunoelectrophoresis. Performance of immunodiffusion in the strips; Separation of protein fractions by thin layer chromatography; Use of cellulose acetate in the method.

Describes a device for preparing cell spreads. Steps involved in preparing a suitable cell suspension; Features of the apparatus used in the process; Instrument's use of centrifugal force to speed up the sedimentation of the cells.

As described in an accompanying paper, trinitrophenyl (TNP) modification of pork insulin (PI) at the A1 glycine position allows this molecule to stimulate a proliferative response in H-2b (B10) mice. We now show that this antigen stimulates low IgG responses in the same strain of mice. Our results show that T-cell help and proliferation may therefore be regulated independently. [ABSTRACT FROM AUTHOR]

It is known that two major cytotoxins, lymphotoxin (LT) and tumour necrosis factor (TNF), are produced by T cells and macrophages, respectively. We report in this paper that a human T-cell hybridoma, AC5-8, produces TNF in addition to LT depending on the kind of stimuli used. When phorbol myristate acetate (PMA) and concanavalin A (Con A) or PMA alone were used to induce AC 5-8 cells to secrete a cytotoxin, we found that the cytotoxin secreted was antigenically indistinguishable from LT. On the other hand, when AC5-8 cells were activated by PMA and A23 187, they secreted another cytotoxin which was antigenically indistinguishable from TNF, in addition to LT. These two cytotoxins could be separated by affinity chromatography on a column of Con A-Sepharose. A cytotoxin, which did not bind to the Con A-Sepharose column and showed about 70- 95% of the total cytotoxic activity secreted from AC5-8 cells stimulated with PMA and A23 187, was found to be antigenically identical to TNK. The other cytotoxin, which bound to the Con A-Sepharose column and showed only 5 - 30% of the total activity induced by PMA and A23 187, was found to be antigenically identical to LT. [ABSTRACT FROM AUTHOR]

MRL-lpr mice and their congenic counterparts MRL- + spontaneously develop an autoimmune disease that resembles systemic lupus erythematosus in humans. The two strains, although congenic, differ by a considerable number of disease parameters, reflecting the expression of the lpr autosomal recessive gene. One paradox that has developed out of the work utilizing the congenic mice is that the gene responsible for lymphoproliferation also appears to be responsible for the inability of T cells to respond to proliferative signals in vitro. In this paper we investigated a possible lpr gene-encoded macrophage defect in these mice. It was found, however, that both the MRL- + and MRL-lpr mice failed to divide in response to Con A, the lack of division correlating with an inability to secrete the growth promoter interleukin-2. In MRL- + mice and young MRL-lpr mice this non-responsiveness was corrected by the addition of normal CRA PEC. The defect could not be explained by a failure of M RL- + or M RL-lpr peritoneal exudate cells to quantitatively or qualitatively provide a source of interleukin-1 to Con A-activated T cells or by the possibility that the peritoneal exudate cells were blocked in their function by the presence of sera-derived autoantibodies and/or immune complexes on their membranes. We postulate that the inability of T cells to proliferate in MRL congenic mice can be explained by two defects: (i) the failure of antigen-presenting cells in MRL- + and MRL-lpr to provide the necessary signals to immunocompetent T cells, this defect not being associated with the lpr gene, and (ii) the lpr gene controlled outgrowth of a unique T-cell population that cannot respond in our assay system. [ABSTRACT FROM AUTHOR]

In a previous paper, we have described a cell-surface associated adhesive glycoprotein (AF) that has been separated and highly purified from rat ascites hepatoma AH136B cells. AF was found to induce the aggregation and adhesiveness of hepatoma cells. AF was also shown to have a mitogenic activity on rat T lymphocytes, and to stimulate them to produce a lymphokine chemotactic for macrophages. In the present paper, we have examined the effects of AF on natural killing (NK) activity by rat spleen cells against NK-sensitive YAC-1 cells using 51Cr-release cytotoxicity assay. NK activity of spleen cells was potentiated by AF treatment in a dose-dependent manner. A short incubation with AF was sufficient for the potentiation of NK activity, whereas the potentiation by OK-432, which is well known as a potentiator of anti-tumour activity, required a longer stimulation. Macrophage depletion from spleen cells resulted in the decreased potentiating effects of OK-432, whereas the depletion failed to influence the effects of AF. In subsequent experiments, it was found that AF could potentiate NK activity of the NK-cell enriched fraction. We further found that culture supernatants from spleen cells and peritoneal exudate cells treated with OK-432 potentiate the NK activity, whereas those from AF-treated cells fail. It was thus suggested that AF acts directly on the cells responsible for NK activity, and that the mechanisms of AF-induced potentiation of NK activity differ from those of OK-432-induced potentiation. [ABSTRACT FROM AUTHOR]

T-colony formation can be induced in PHA-stimulated peripheral blood mononuclear cells (PBM) from man, but not in PHA-stimulated purified T cells, the latter requiring the presence of factors produced by PHA-stimulated PBM and termed T-colony promoting activity (TCPA). In this paper, we demonstrate that interleukin-2 (IL-2), the growth hormone of T lymphocytes, controls T-colony formation. We show that: (i) IL-2 activity and TCPA produced by PHA-activated PBM are co-purified by gel filtration and chromatography on blue agarose, a procedure which yields a 850-fold IL-2 purification; (ii) recombinant IL-2, produced by genetically manipulated Eseherichia coli, can induce T-colony formation in PHA-stimulated purified T cells; (iii) Monoclonal antibody against the IL-2 receptor (anti-Tac antibody) completely inhibits the T-colony formation in PHA-stimulated PBM when directly added to the culture system. [ABSTRACT FROM AUTHOR]

Several hybridoma cell lines secreting NP-specific, murine IgE antibodies were generated by fusion of P3-X20 (γ,κ) tumour cells with spleen cells from (BALB/c x C57Bl/6)F1 (CB6F1) mice previously immunized with NP-ovalbumin. Four subclones (designated NP-ε-3.57, NP-ε-15,88, NP-ε-91,58 and NP-ε-95,31) were propagated in vivo and milligram quantities of the corresponding IgE antibodies were purified from ascitic fluid by gel filtration, ion exchange chromatography and affinity chromatography. Immunological analyses and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDSPAGE) indicated that NP-ε-15,88, NP-ε-91,58 and NP-ε-95.31 all possessed λ1 (or possibly λ3) light chains; and that NP-ε-3,57 possessed λ2 light chains; NP-&elipson;-95,31 also expressed the P3-X20 derived, MOPC-21 κ light chain. Radioallergosorbent test (RAST) titration curves, generated from the interaction of the four monoclonal IgE antibodies with NP-BSA attached to paper discs (NP-BSA-P) were found to be non-overlapping. Measurements of the relative amounts of NP-ε-aminocaproic acid (NP-CAP) and 4-hydro-3-iodo-5-nitrophenylacetyl-ε- aminocaproic acid (NIP-CAP) that were required to inhibit by 50% the binding of the 4 IgE antibodies to NP-BSA-P indicated that these antibodies were all heteroclitic, since their affinity for NIP appeared to be higher than their affinity for NP. These results, in conjunction with other findings reported in the literature, suggested that the V regions of NP-specific IgE antibodies are similar to the V regions of NP-specific IgM and IgG antibodies, produced by the same mouse strains. Finally, in vitro histamine release measurements demonstrated that two of these monoclonal IgE antibodies could mediate antigen induced histamine release from passively sensitized rat peritoneal mast cells. [ABSTRACT FROM AUTHOR]

The fractionation of a partially-purified extract of Dermatophagoïdes farinae mite culture has been undertaken by gel filtration. Two fractions were isolated. One, P25, is a protein-rich fraction with mol. wt about 25,000. The other, GP8, is a polysaccharide-rich fraction with mol. wt around 8,000. By crossed immunoelectrophoresis, we detected eleven antigens in the partially-purified dialysed D. farinae extract (Df 80d) as well as in P25 fraction. One of them, ag 11, seems the most important allergen since in crossed-radio immunoelectrophoresis experiments it displays the faster radiostaining, implying that it binds the greatest part of the mite-specific IgE present in a pool of sera from mite-sensitive patients. By crossed-line immunoelectrophoresis, we demonstrated the absence of ag 11 in GP8, in which only ag 5 and ag 6 were identifiable. By radioalloergosorbent tests (RAST), it was found that P25- and GP8- coated paper discs can fix specific IgE induced in the majority of D. farinae sensitive patients. Defining a ‘major allergen’ as an allergen to which the majority of sensitive patients develop specific IgE, both P25 and GP8 do appear to contain at least one major allergen. By RAST inhibition method, using Df 80d as a solid phase, the allergenic activity of P25 appeared as slightly higher than that of Df 80d, whereas GP8 displayed a very weak inhibitor capacity. Thus, the allergic specificity of GP8 differs from that of Df 80d or P25. [ABSTRACT FROM AUTHOR]

This paper describes the specificity of delayed-type hypersensitivity (DH) and antibody formation in the mouse to the tripeptide-enlarged hapten, 3-(p-azobenzenearsonate)-N-acetyl-L-tyrosylglycylglycine (A). Hapten A was coupled to phosphatidylethanolamine (PE) and incorporated into liposomal membranes (A PE-liposomes). DH was measured as footpad swelling and antibody formation by the enumeration of direct plaque-forming cells in the spleen. A-PE-liposomes mixed with the cationic, surface-active lipid, dimethyl dioctadecyl ammonium bromide (DDA) induce, on intracutaneous injection in mice, hapten-specific DH without a contribution by the carrier. With other haptenated liposomes it was not possible to induce DH to those haptens, including the closely related hapten 3-(p-azobenzenesulphonate)-N-acetyl-L-tyrosylglycylglycine (S). A-PE- and S-PE-liposomes evoke, after intravenous injection in mice, a humoral response. The antibody formation to A-PE-liposomes was thymus-independent. In this response a considerable cross reaction between haptens A and S was observed. [ABSTRACT FROM AUTHOR]

Our earlier observations indicate that adoptive transfer of spleen cells obtained from dengue type 2 virus (DV)-primed mice suppressed DV antigen-specific antibody secretion as detected by Jerne PFC technique. Findings of this paper indicate that the suppression was produced by non-glass-adherent cells, macrophage-depleted (by carbonyl iron) cells and by T lymphocytes of the spleen but not by the glass-adherent cells and B lymphocytes. The activity of these cells is dependent upon production of prostaglandin as shown by abrogation of their suppressor activity by pre-treatment of cells by indomethacin or aspirin which are known to block synthesis of prostaglandins. [ABSTRACT FROM AUTHOR]

The method described in the previous paper was used to induce secondary responses in spleen cells from CBA/H mice, pre-primed with lymphocytic choriomeningitis (LCM) virus by culturing them with LCM-infected peritoneal cells. The cytolytic effector cells thus generated have been characterized. Effector cells were sensitive to treatment with anti-θ ascitic fluid and complement. Separation procedures based on rosetting of certain categories of lymphocytes with sheep red cells through an isopaque-Ficoll gradient indicated that effector cells lacked surface immunoglobulin and generally did not bear Fc receptors. Cytolytic activity was restricted by the H-2 gene complex. Killing had single-hit characteristics. All these results suggested that the cells from memory cultures mediating cytolysis were T cells. There was evidence for two T cell subsets, a major subpopulation directed against antigens on infected targets and a minor one directed against antigens on uninfected, H-2-compatible targets. Specificity was present at the infected cell: memory responder and killer:target levels between LCM virus (an arenavirus) and ectromelia virus (a poxvirus). [ABSTRACT FROM AUTHOR]

We have established previously that human thyroid epithelial cells (TEC) from patients with autoimmune thyroiditis are able to synthesize cytokines, such as interleukin-1(IL-1) and interleukin-6(IL-6). This paper examines TEC in sections from autoimmune thyroiditis for the in vivo production of tumour necrosis factor-alpha (TNF-α) and interferon-gamma (IFN-γ) using the combined techniques of in situ hybridization and immunohistochemistry. Thyroid tissue from patients with Graves' disease, Hashimoto's disease and non-toxic goitre was examined and both mRNA and the protein of TNF-α were detected in TEC on frozen sections. Representative figures of only Graves' samples are illustrated in this paper. In contrast, using the same methods, IFN-γ was detected only in the infiltrating cells and not in TEC of thyroid tissue from the patients. [ABSTRACT FROM AUTHOR]

Heat and pH stability studies and experiments with organic solvents show that the A-antigens discussed in the preceding paper (Augustin, 1959c) are much more labile than the I-(‘inner ring’) antigens. Breakdown products and/or aggregates are produced which no longer precipitate with antisera to the original extracts, but act as inhibitors. Solutions of pollen allergens, on the other hand, are found to withstand even autoclaving for 15 min. at 20 atm. and vigorous boiling over the naked flame of a bunsen burner. None of the carbohydrates tested has a demonstrable effect on skin reactivity which is, however, destroyed by crystalline pepsin, crystalline trypsin, a crystalline mould protease and a tissue protease (a partially purified extract from rabbit spleen). It follows that the bulk of the allergens—if not all—are proteins. The relation of skin reactivity, immuno-electrophoretic patterns, carbohydrate and protein reactions to the selective destruction of the pollen antigens is investigated. Pollen components prove to have a somewhat wider range of electrophoretic mobilities than serum proteins and are probably as complicated a mixture. The most and least highly negatively charged components are without skin reactivity in allergic subjects. The skin reactive allergens appear to have the mobilities of α- and β-globulins. Not all the hay fever subjects react equally to all the components, and Cocksfoot and Timothy activity patterns vary in different subjects. [ABSTRACT FROM AUTHOR]

It has previously been shown that rats do not expel a primary infection of Nippostronglus brasiliensis during lactation. In the present paper, three aspects of the immune response of the lactating rat to the parasite were examined and compared with the response of non-lactating rats. Protective and reaginic antibodies were present in the circulation of rats first infected during lactation, in titres as high or higher than those in non-lactating controls. The intestinal mast cell response was similar both in timing and magnitude and lactating rats became susceptible to shock with the i.v. injection of antigen. Attention was drawn to the similarity between the response of the lactating rat and that of the neonate to this infection. [ABSTRACT FROM AUTHOR]

In the previous paper we showed that the immune response to sheep red cells (SRBC) was degenerate; serum antibodies showed increasing loss of specificity, signalled by cross-reactions with horse RBC (HRBC), with time after immunization and with hyperimmunization. In the present report we have analysed the role T cells may play in this process. To do this we studied the antibodies made by mice deprived of T cells by irradiation as well as those made by normal mice immunized with SRBC in distilled water, which was shown to depress the DNA synthetic response of T cells. In both instances the mice with fewer responding T cells made less antibody which could agglutinate HRBC than did the appropriate controls. This was true even when no difference in anti-SRBC titre was apparent. In addition we showed that the antibody made by mice with reduced numbers of T cells was less effective at passive suppression of the immune response to SRBC than was similarly titred (against SRBC) antibody made by normal mice. Thus, certain sub-populations of antibodies, normally made in response to SRBC, immunization, are particularly thymus dependent. We have discussed why we think they are those of particularly high affinity. [ABSTRACT FROM AUTHOR]

Summary: Mass vaccination of the global population against SARS‐CoV‐2 will, we hope, turn the tide against this devastating pandemic. To complement vaccinations, better tools are needed to enable viral infections and immunological protection to be monitored. Accurate tools provide sound data for informed decision‐making at many levels, from personal to governmental. The measurement of viral RNA is currently routinely used to detect active infections, but only gives a positive result during infection and is unable to reveal historic infections. Tests involving a detection of SARS‐CoV‐2‐specific antibodies can reveal prior exposures to virus and can measure anti‐viral immune responses induced after natural infection or after vaccination. They may eventually also be used to predict an individual's likelihood of becoming re‐infected. Here, we report on the development of a sensitive ELISA technique to detect multiple isotypes of antibodies against the spike glycoprotein, in samples of both serum and saliva. This paper provides an important step towards understanding the immune response to SARS‐CoV‐2 and may therefore eventually help us to effectively control it. [ABSTRACT FROM AUTHOR]

Summary: Hepatitis B virus (HBV) infection causes a self‐limiting disease in most individuals. However, < 10% of infected subjects develop a chronic disease. Genetic host variability of polymorphic genes at the interface of innate and acquired immunity, such as killer immunoglobulin‐like receptors (KIR), their human leucocyte antigen (HLA) and IgG allotypes (GM), could explain this different clinical picture. We previously showed a protective role of the KIR2DL3 gene for the development of chronic hepatitis B (CHB), and a detrimental role of the KIR ligand groups, HLA‐A‐Bw4 and HLA‐C2. We have expanded the previous analysis genotyping patients for GM23 and GM3/17 allotypes. The comparison of the patients with CHB with those who resolved HBV infection showed that the presence of GM17 allele virtually eliminated the risk of developing CHB (OR, 0·03; 95% CI, 0·004–0·16; P < 0·0001). In addition, the combination of GM17, KIR2DL3, HLA‐A‐Bw4 and HLA‐C2 was highly sensitive to predict the outcome of HBV infection. [ABSTRACT FROM AUTHOR]

We had several manuscripts out for review, grants submitted and a looming move of our lab to an updated new facility down the street. It could be a junior faculty member submitting grant after grant only to get a dreaded "ND" weeks later, time and time again. I have also thought about if "science burnout" is distinct from that experienced in other life paths. [Extracted from the article]

In a companion article to this study,1 the successful programming of a JAWSII dendritic cell ( DC) line's antigen uptake and processing was demonstrated based on pre-treatment of DCs with a specific 'cocktail' of select chemokines. Chemokine pre-treatment modulated cytokine production before and after DC maturation [by lipopolysaccharide (LPS)]. After DC maturation, it induced an antigen uptake and processing capacity at levels 36% and 82% higher than in immature DCs, respectively. Such programming proffers a potential new approach to enhance vaccine efficiency. Unfortunately, simply enhancing antigen uptake does not guarantee the desired activation and proliferation of lymphocytes, e.g. CD4+ T cells. In this study, phenotype changes and antigen presentation capacity of chemokine pre-treated murine bone marrow-derived DCs were examined in long-term co-culture with antigen-specific CD4+ T cells to quantify how chemokine pre-treatment may impact the adaptive immune response. When a model antigen, ovalbumin ( OVA), was added after intentional LPS maturation of chemokine-treated DCs, OVA-biased CD4+ T-cell proliferation was initiated from ~ 100% more undivided naive T cells as compared to DCs treated only with LPS. Secretion of the cytokines interferon-γ, interleukin-1β, interleukin-2 and interleukin-10 in the CD4+ T cell : DC co-culture (with or without chemokine pre-treatment) were essentially the same. Chemokine programming of DCs with a 7 : 3 ratio of CCL3 : CCL19 followed by LPS treatment maintained partial immature phenotypes of DCs, as indicated by surface marker ( CD80 and CD86) expression over time. Results here and in our companion paper suggest that chemokine programming of DCs may provide a novel immunotherapy strategy to obviate the natural endocytosis limit of DC antigen uptake, thus potentially increasing DC-based vaccine efficiency. [ABSTRACT FROM AUTHOR]

Natural killer ( NK) cells provide an immediate first line of defence against viral infections. Memory responses, maintained by CD4+ T cells, require exposure to viral antigen and provide long-term protection against future infections. It is known that NK cells can promote the development of the adaptive response through cytokine production and cross-talk with antigen-presenting cells. In this paper however, we summarize a series of recent publications, in mouse models and for the first time in man, with the unifying message that rapid viral antigen control by the innate immune system limits antigen exposure to CD4+ cells thereby abrogating the development of a memory response. We discuss the significant implication of these studies on viral treatment strategies and immunization models. [ABSTRACT FROM AUTHOR]

Summary The bacterial superantigen exotoxins of Staphylococcus aureus and Streptococcus pyogenes are potent stimulators of polyclonal T-cell proliferation. They are the causes of toxic shock syndrome but also induce CD25+ FOXP3+ regulatory cells in the CD4 compartment. Several studies have recently described different forms of antigen-induced regulatory CD8+ T cells in the context of inflammatory diseases and chronic viral infections. In this paper we show that bacterial superantigens are potent inducers of human regulatory CD8+ T cells. We used four prototypic superantigens of S. aureus (toxic shock syndrome toxin-1 and staphylococcal enterotoxin A) and Str. pyogenes (streptococcal pyrogenic exotoxins A and K/L). At concentrations below 1 ng/ml each toxin triggers concentration-dependent T-cell receptor Vβ-specific expression of CD25 and FOXP3 on CD8+ T cells. This effect is independent of CD4+ T-cell help but requires antigen-presenting cells for maximum effect. The cells also express the activation/regulatory markers cytotoxic T-lymphocyte antigen-4 and glucocorticoid-induced tumour necrosis factor receptor-related protein and skin homing adhesins CD103 and cutaneous lymphocyte-associated antigen. Superantigen-induced CD25+ FOXP3+ CD8+ T cells were as potent as freshly prepared naturally occurring CD4+ regulatory T cells in suppressing proliferation of CD4+ CD25− T cells in response to anti-CD3 stimulation. Although superantigen-induced CD8+ CD25+ FOXP3+ express interleukin-10 and interferon-γ their suppressive function is cell contact dependent. Our findings indicate that regulatory CD8+ T cells may be a feature of acute bacterial infections contributing to immune evasion by the microbe and disease pathogenesis. The presence and magnitude of regulatory CD8+ T-cell responses may represent a novel biomarker in such infections. Superantigen-induced regulatory CD8+ T cells also have therapeutic potential. [ABSTRACT FROM AUTHOR]

This paper describes an experimental model of neuroinflammation based on the production of interleukin-6 (IL-6) by neural glial cells infected with Theiler's murine encephalomyelitis virus (TMEV). Production of IL-6 mRNA in mock-infected and TMEV-infected SJL/J murine astrocytes was examined using the Affymetrix murine genome U74v2 DNA microarray. The IL-6 mRNA from infected cells showed an eightfold increase in hybridization to a sequence encoding IL-6 located on chromosome number 5. Quantitative real-time reverse transcription PCR (qPCR) was used to study the regulation of IL-6 expression. The presence of IL-6 in the supernatants of TMEV-infected astrocyte cultures was quantified by ELISA and found to be weaker than in cultures of infected macrophages. The IL-6 was induced by whole TMEV virions, but not by Ad.βGal adenovirus, purified TMEV capsid proteins, or UV-inactivated virus. Two recombinant inflammatory cytokines, IL-1α and tumour necrosis factor-α were also found to be potent inducers of IL-6. The secreted IL-6 was biologically active because it fully supported B9 hybridoma proliferation in a [H]thymidine incorporation bioassay. The cerebrospinal fluid of infected mice contained IL-6 during the acute encephalitis phase, peaking at days 2-4 post-infection. Finally, this in vitro neuroinflammation model was fully inhibited, as demonstrated by ELISA and qPCR, by five selective oestrogen receptor modulators. [ABSTRACT FROM AUTHOR]

Removal of apoptotic cells from inflammatory sites by macrophages is an important step in the resolution of inflammation. However, the effect of inflammatory modulators on phagocytic clearance of apoptotic cells remains to be clarified. In this paper, we demonstrate that lipopolysaccharide (LPS), a potent inflammatory agent, inhibits the phagocytosis of apoptotic neutrophils by mouse peritoneal macrophages. This inhibition can be attributed to both LPS-mediated induction of tumour necrosis factor (TNF-α) and suppression of growth arrest-specific gene 6 (Gas6) in macrophages. We found that LPS-induced TNF-α production inhibited phagocytic ability of macrophages in an autocrine manner. In contrast, Gas6 expression in macrophages was blocked by LPS, which also contributes to the inhibition of macrophage phagocytosis by LPS. Our data suggest that phagocytic clearance of apoptotic neutrophils by macrophages can be regulated by local pro- and anti-inflammatory factors in two opposite states. [ABSTRACT FROM AUTHOR]

Peripheral blood CD4 CD45RO T cells activated in vitro are able to induce expression of tumour necrosis factor-α (TNF-α) in monocytes via a contact-dependent mechanism. Activation is achieved either with interleukin-2 (IL-2)/IL-6/TNF-α over an 8-day period or cross-linking CD3 using anti-CD3 antibody for 48 hr. In this paper, we show that the p38 mitogen-activated protein kinase (MAPK) signalling pathway played different roles in the generation of effector function in these two types of activated T cells. In anti-CD3 activated T cells, p38 MAPK is a negative regulator for anti-CD3 induced cell proliferation and has no significant effect on the acquisition of either the effector function (induction of monocyte-derived TNF-α) or production of T-cell cytokines. In contrast, the p38 MAPK signalling pathway is required for the acquisition of cytokine-induced effector function and promotes cell proliferation and cytokine production. [ABSTRACT FROM AUTHOR]

The ultimate outcome of T cell receptor recognition is determined by the context in which the antigen is encountered. In this fashion both antigen-presenting cells and T cells must integrate multiple environmental cues in the form of pathogen-associated molecular patterns, cytokines and accessory molecule signals. The mammalian target of rapamycin (mTOR) is an evolutionarily conserved serine/threonine kinase that plays a central role in integrating environmental signals critical to regulating metabolism and cell survival. In this paper we review the data demonstrating that mTOR integrates signals from the immune microenvironment and therefore facilitates the generation of the adaptive immune response. Specifically, we review the role of mTOR in promoting dendritic cell activation and maturation, in regulating full T cell activation versus anergy, and influencing the induction of regulatory T cells. [ABSTRACT FROM AUTHOR]