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Protective immunity against mycobacteria is dependent on antigen-specific T cells. The antibodies induced upon immunization with mycobacteria have no apparent role in host protection, Serological techniques have detected some antigens that are also recognized by human T cells but may fail to recognize others. Potentially, there may be differences in the epitopes seen by the T and B cell anti-mycobacterial antigen repertoires. We have screened the different components of sonicated BCG or Mycobacterium leprae that were separated according to their molecular weight (MW) by SDS-PAGE and then electroblotted on nitrocellulose paper. The blots were cut into squares and tested directly in a T cell proliferation assay. Our results indicate that peripheral T cells of healthy leprosy patient contacts respond preferentially to the lower MW (<70,000) and not the higher MW fractions of M. leprae and BCG, in contrast to the humoral response of these same individuals. The most important fractions in inducing a lymphoproliferative response were in the regions of 11-16 kDa of BCG and M. leprae and to the 22-26 kDa region of M. leprae. These fractions appeared to represent molecular weight regions that were in some instances clearly distinct from previously defined antigens. It was further shown that lymphoproliferation in response to mycobacterial fractions correlated with the production of gamma interferon, a lymphokine required for macrophage activation and elimination of mycobacteria. These studios allow the direct assessment of antigens involved in protective T cell-mediated immunity, and should be helpful in selecting relevant antigens for skin testing and immunization. [ABSTRACT FROM AUTHOR]

Intrasplenic immunization with antigen immobilized on nitrocellulose (NC) paper results in an immune response with nanogram amounts of antigen without the use of Freund's adjuvant. Comparing the sensitivity of the intrasplenic immunization with intraperitoneal or subcutaneous administration, we found that the intrasplenic method resulted in more positive animals with higher titres than did the other techniques with the smallest amount of antigen (70 ng of bovine serum albumin). With larger amounts of albumin the intraperitoneal method yielded the highest titres. No loss of antigenicity was observed when we immunized with equal amounts of protein separated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), immunoblotted and stained with either Coomassie brilliant blue R 250 or Amido black 10 B. [ABSTRACT FROM AUTHOR]

Antigen 60 (A60), a member of the thermostable macromolecular antigen family (TMA) and main component of old tuberculin and purified protein derivative (PPD), has been purified from the cytoplasm of Mycobacterium bovis BCG; its structure and metabolism have already been described. In the present paper, the action of A60 on humoral immunity has been analysed by an ELISA type immunoassay, and that on cellular immunity by the mouse footpad swelling test. Injection of very low A60 doses into unprimed mice produced an undetectable level of anti-A60 antibodies: the effect or a booster inoculation was not appreciable in the absence of incomplete Freund's adjuvant, but was evident when the latter was added. Higher doses of the antigen produced an appreciable primary response, and a sharp and long-lasting secondary response, which had a 10-fold higher intensity in the presence of incomplete adjuvant. No detectable delayed hypersensitivity reactions were observed in unprimed mice after footpad injection of A60, whereas clear responses were elicited in primed mice. This effect was more pronounced when the footpad was injected after a secondary response than after a primary response, and it was invariably magnified by incomplete adjuvant. It is concluded that A60 is a powerful immunogen, which is able to induce primary and secondary responses and delayed hypersensitivity reactions, effects that are adjuvant-modulated and develop concurrently. [ABSTRACT FROM AUTHOR]

Optimal proliferative response of T lymphocytes to purified protein derivative of tuberculin (PPD) in vitro requires that antigen be presented by autologous macrophages or allogeneic macrophages sharing HLA-D/DR determinants with the T cell donor. In some cases, however, T cells may respond to a limited extent to PPD in association with macrophages expressing different HLA-D/DR determinants. In this paper experiments are presented where various combinations of T cells and HLA-D/DR disparate macrophages were stimulated with PPD. We often found a strong PPD-specific response in HLA-D/DR-incompatible combinations in which the macrophages carried HLA-DR antigens known from serological studies to be cross-reactive with those of the T cell donor than in combinations in which this was not the case. Thus, the cross-reactions detected by serology may sometimes be reflected on a functional level in T lymphocyte/macrophages cooperation. [ABSTRACT FROM AUTHOR]

The article presents abstracts of several research papers published in different journals. One of the abstracts is on quantitative studies describing the in vivo behavior of an inhaled protein antigen. Aerosol mists were generated from bovine serum albumin (BSA) solutions. The fate of inhaled BSA in vivo was studied in rabbits by using a paired-isotope technique to quantitative antigen sequestration within organs. The study suggests that antigen inhalation may function primarily as an important physiologic means by which natural immunity to environmental antigens is established. Another abstract discusses relationship of serum theophylline concentration to inhibition of exercise-induced bronchospasm and comparison with cromolyn. The effect of cromolyn in suppressing exercise-induced bronchospasm was generally much less.

The experiments described in this paper extend the observations of previous work in vitro demonstrating a decrease in the frequency of antigenreactive units specific for horse RBC in spleen cells from mice primed with KLH. It was observed that the addition of lymphoid cells having T-cell function reconstituted the anti-HRBC response to normal values. Significant enhancement of the response beyond the normal values could be evoked using two dissimilar methods, (i) addition of allogeneic thymus cells, and (ii) restimulation in vitro with the priming antigen. The latter type enhancement was elicited by the addition of small doses of KLH to cultures of spleen cells from mice recently primed with KLH, including cultures otherwise demonstrating antigen-induced suppression. The stimulus required to enhance the response to HRBC in these cultures was specific for the priming antigen, KLH. These results are discussed in the light of current theories of 'antigenic competition' and specific heterologous enhancement. [ABSTRACT FROM AUTHOR]

When lymphoid cells from hypersensitive rabbits are incubated with antigen, biologically active substances are formed and released which are capable of inhibiting the migration of normal non-sensitized mesenchymal cells. In the present paper some basic parameters of their production were determined. These substances were regularly obtained after 6 and 18 hours incubation, but not after 2 hours. Under more favourable cultivation conditions (lower density of lymphocyte suspension) an increased activity in the cell extracts as compared with the supernatants was observed. Another critical factor in the production of these substances is the quantity of antigen added. Ten micrograms of PPD leads to the production and liberation of a highly effective substance. A lower dose of antigen results in the liberation of a substance into the supernatant which by itself is almost inactive, but becomes more active when more antigen is added. The efficiency of the released substances was determined by serial dilution. The inhibiting activity was maintained at 1:5 and 1:20 and sometimes at 1:100 dilutions. [ABSTRACT FROM AUTHOR]

This paper describes a form of red cell lysis differentiated from classical complement haemolysis by its occurrence in the absence of antibody on the cells and in the presence of EDTA. This type of haemolysis has been called reactive haemolysis. It is the result of the interaction, in the presence of red cells, of at least two serum factors called ‘reactor’ and ‘indicator’, respectively. Reactor only becomes active after incubation at 37° of serum with certain agents, notably antibody-coated bacteria, zymosan and agarose, in conditions similar to those required for complement activation. The potential for the formation of activated reactor could be demonstrated infrequently in healthy subjects but more frequently in sera from hospital patients. Activated reactor behaved as a protein sedimenting between 7S and 19S, and of α2-β1, electrophoretic mobility in agar. Indicator factors were present in all human sera studied, as well as in the sera of a number of mammalian species. They were demonstrable at high dilutions of the serum and required no prior activation for their action. They occurred maximally in the 7S fractions of serum proteins and migrated in the β2 position on electrophoresis. Reactive haemolysis was first observed and can most conveniently lie demonstrated in a red cell-agarose gel. It can also be demonstrated in the test tube following partial purification of activated reactor and indicator factors. Studies in the test tube indicated that a .soluble labile lytic factor was responsible for this type of haemolysis, [ABSTRACT FROM AUTHOR]

Rat liver microsomes were separated into three subfractions by means of ultracentrifugation through sucrose media of different densities and in the presence of different cations. Detergent extracts of these preparations were analysed by double diffusion in agar gel and immunoelectrophoresis with rabbit antisera against each of the subfractions. One subfraction was derived from the ‘rough’ and another from the ‘smooth’ part of the endoplasmic reticulum of the liver parenchymal cells. Their extracts contained at least thirteen soluble antigens in common. However, fraction-specific antigens were also present. Thus, the extracts of the rough (R) membranes contained at least one typical antigen, not found in any of the other fractions. An antiserum against this component also precipitated a non-migrating antigen present only in the extracts of smooth (Sa) membranes. These two antigens may represent different molecular forms of a substance involved in binding of the ribosomes or in the assembly of membrane subunits. At least eleven of the antigens common for the two fractions exhibited enzymatic activities when assayed after precipitation with antibody in the immunoelectro- phoretic plates. Six immunologically and electrophoretically distinct antigens had esterase activity with α-naphthyl propionate as substrate. Two of these esterases also split indoxyl acetate. Three other antigens with acid phosphatase activity split both α-naphthyl acid phosphate and β-glycerophosphate. Three antigens had nucleoside diphosphatase activity when tested with uridine- or inosine-diphosphate. Preliminary experiments also suggested that two additional antigens possessed NADH-diaphorase activity and thus could belong to the microsomal electron trans- port systems. The third subfraction consisted of electron-microscopically smooth membranes (Sb), enzymatically different from those of the endoplasmic reticulum. The antigens typical for the latter were either absent or present only in minor and variable concentrations. Its extracts contained at least two typical antigens. One of these was identified as contaminating ferritin. The nature and origin of the other antigen has not yet been established. All antigens described in this paper were immunologically different from the common rat serum proteins. [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]

The article presents abstracts of research papers about astrocyte biology and neuronal-glial interactions. They include "Connexin 43 regulates contact-directed distribution of exocytotic fusion sites on astrocytes," "Monitoring of exocytosis in astrocytes using synapto-pHluorins and total internal reflection fluorescence microscopy," "Effect of monocarboxylate transporter inhibition on NADH biphasic response and oxygen utilization after neuronal stimulation," and "Involvement of PI3-K/Akt signal pathway in acquired resistance against 6-OHDA in SH-SY5Ycell following interaction with astrocytes."

At least a dozen countries or states in the world have introduced vaccine injury compensation schemes. This paper argues that the Australian Government should introduce such a scheme, which may reduce litigation, and may improve consumer and provider confidence. The most important justification, however, is an ethical argument from justice and equity: introduction of a vaccine injury compensation scheme acknowledges the unique situation that routine childhood immunization is a public health measure, given and accepted in good faith, that may occasionally damage the recipient. [ABSTRACT FROM AUTHOR]

Hinze-Selch D. Infection, treatment and immune response in patients with bipolar disorder versus patients with major depression, schizophrenia or healthy controls. Bipolar Disord 2002: 4(Suppl. 1): 81–83. ©Blackwell Munksgaard, 2002 Bipolar disorder is the least studied among the three major psychiatric disorders of schizophrenia, major depression and bipolar disorder. Furthermore, investigations on infection and immunity in bipolar disorder make up only a small portion of the sparse research done on this disorder. However, there are reports that modulation of the immune system and certain infections might be associated with bipolar disorder and that there might be differences between bipolar and the other disorders. The purpose of this paper is to briefly review published data on these issues in bipolar versus the other disorders, and to present an ongoing clinical study on the putative involvement of infection with the parasite Toxoplasma gondii in these three major psychiatric disorders. [ABSTRACT FROM AUTHOR]

The article focuses on purification and characterization of atopic allergens. In the past two decades, several atopic allergens, which induce IgE antibody-mediated immediate hypersensitivity in man have been purified to near homogeneity and studied for their immunochemical properties. In this paper will be reviewed some of the general findings drawn from such studies. Allergen characterization studies with extracts from these sources have confirmed the views of allergists that all extracts are multi-allergen systems and that individuals can have varying patterns of sensitivity to different allergens.

Click here to view the accompanying paper in this issue. [ABSTRACT FROM AUTHOR]

The article presents abstracts of research papers about blood brain barrier and its role in immune privilege in the CNS in health and disease. They include "Heterogeneity of the CNS microvasculature," "Reactive oxygen species and pathological events in multiple sclerosis," "Dendritic cell migration across the blood-brain barrier is mediated via tight junctions in mmp-dependent way," and "Blood-brain barrier transmigration of human monocytes induces their differentiation into dendritic cells."

The article presents abstracts of research papers about the role of the helper type T lymphocytes Th1 and Th2 in neural injury and disease. They include "Th1/Th2 cell primer," "Th1/Th2 cell balance in neural repair after peripheral nerve injury," "Th1-biased immunity after spinal cord injury: implications for neurodegeneration and host defense," and "Chemokine and chemokine receptor regulation of autoimmune encephalomyelitis."

Presents an index of the subjects of research papers published in the 1988 issues of the periodical "Immunology,". C-reactive protein; CD4+ cells; HIV proteins; Eosinophils.

An abstract of the research paper "Towards a better understanding of the developmental origins of disease," by R. Nanan is presented.

Virulence is generally considered to benefit parasites by enhancing resource-transfer from host to pathogen. Here, we offer an alternative framework where virulent immune-provoking behaviours and enhanced immune resistance are joint tactics of invading pathogens to eliminate resident competitors (transferring resources from resident to invading pathogen). The pathogen wins by creating a novel immunological challenge to which it is already adapted. We analyse a general ecological model of ‘proactive invasion’ where invaders not adapted to a local environment can succeed by changing it to one where they are better adapted than residents. However, the two-trait nature of the ‘proactive’ strategy (provocation of, and adaptation to environmental change) presents an evolutionary conundrum, as neither trait alone is favoured in a homogenous host population. We show that this conundrum can be resolved by allowing for host heterogeneity. We relate our model to emerging empirical findings on immunological mediation of parasite competition. [ABSTRACT FROM AUTHOR]

We have examined psychosocial and immune system stress responses in gay men before and after their notification of human immunodeficiency virus (HIV-1) status and as a consequence of stress management intervention procedures. Prior to notification, early stage, asymptomatic, seropositive men displayed compromised immunity as evidenced by significant decreases in CD4+ cell number, the helper subset (CD29+CD4+), CD4+/CD8+ ratio, and lymphocyte responses to mitogens. Prior to diagnosis, both seronegative and seropositive men revealed suppression of NK cell cytotoxicity and mitogen responsivity relative to matched laboratory control subjects not awaiting diagnosis. Immune suppression in these seronegative men disappeared after diagnosis, indicating its relationship to anticipation of serostatus notification. We also found that a 10-week program of aerobic exercise or psychosocial stress management buffered the psychological impact of notification of seropositivity. The aerobic exercise program produced a significant increase in CD+ and NKH.I + for seronegatives and CD45R + CD4+ cell number and mitogen responsivity for seropositives. We are assessing our interventions as tools for retarding immune deterioration and disease progression in HIV-1 seropositive individuals. [ABSTRACT FROM AUTHOR]

Aiming at the display fragmentation caused by insufficient module strength of ultra-thin and narrow design, a module strength prediction model is proposed to improve LCDs strength immunity and provide design guide, The comparison between the experiment measurement and the predicted results shows that the model can accurately predict the module strength under different design conditions and provide effective technical support and guidance. [ABSTRACT FROM AUTHOR]

Low vaccine immunogenicity and tumor heterogenicity greatly limit the therapeutic effect of tumor vaccine. In this study, a novel injectable adhesive hydrogel, based on thermosensitive nanogels containing catechol groups and loaded with in situ‐forming MnO2 nanoparticles, is constructed to overcome these issues. The concentrated nanogel dispersion transforms into an adhesive hydrogel in situ after intratumoral injection. The photothermal effect of the loaded MnO2 nanoparticles induces immunogenic cell death to release mass autologous tumor‐derived protein antigens under near‐infrared irradiation, which act as ideal immune stimulating substances avoiding the problem of tumor heterogenicity and are captured by the in situ‐forming adhesive hydrogel. The antigens‐captured adhesive hydrogel acts as an "antigen reservoir" and releases these captured antigens to recruit more dendritic cells to stimulate an intensive and lasting anti‐tumor immune response mediated by CD8+ T cells. The primary tumors can be almost completely disappeared within 4 days without relapse, and the growth of the distal tumors and rechallenged tumors are also effectively inhibited by the treatment with the injectable adhesive hydrogel‐based photothermal therapy. Therefore, the proposed "antigen reservoir" strategy shows the great potential application as an in situ‐forming personalized vaccine to enhancing the cancer immune therapy. [ABSTRACT FROM AUTHOR]