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Short-term (3 hr) incubation of whole blood with human recombinant cytokines induced rapid changes in the expression of monocyte but not of lymphocyte surface molecules. The percentage of monocytes bearing CD11b molecules was enhanced by tumour necrosis factor-beta (TNF-α), whilst that of CD11c was increased by both TNF-α and TNF-β. The mean fluorescence intensity (MFI) of monocyte CD11a was enhanced by interleukin-2 (IL-2), TNF-α and TNF-β, and that of CD11b. CD11c and CD18 was increased by IL-2, IL-4, TNF-α and TNF-β. The proportion of monocytes expressing HLA-DR antigens was not modified by the cytokines investigated, but its MFI was increased by IL-2, IL-4, TNF-α and TNF-β. In contrast, the percentage of monocytes bearing complement receptor 1 (CD35) was enhanced by IL-2, TNF-α and TNF-β but the MFI of this molecule was not modified by these cytokines. The highest up-regulation of CD18, HLA-DR and CD35 was observed with 100 U/ml of either IL-2. IL-4, TNF-α or TNF-β. Decreasing the concentration of all four cytokines from 100 to 10 and 1 U/ml diminished the levels of expression of all molecules, with the exception of CD35, which reached its maximum upon incubation with I U/ml of TNF-α. IL-1β, IL-6 or interferon-gamma (IFN-γ) did not modify the expression of any of the above monocyte surface determinants. Moreover, none of the lymphocyte surface molecules investigated was modified by 3-hr incubation of blood with cytokines. The demonstration that cytokines selectively and rapidly up-regulate integrins, complement receptor 1 and HLA-DR molecules, on monocytes but not on lymphocytes, suggests that similar mechanisms of mononuclear cell activation by cytokines may control the development and duration of the inflammatory process. [ABSTRACT FROM AUTHOR]

The percentage of human granulocytes expressing the integrins CD11b and CD11c as well as complement receptor 1 (CD35) was increased by short-term incubation of whole blood with interleukin-2 (IL-2), interleukin-4 (IL-4) and tumour necrosis factors alpha and beta (TNF-α and TNF-β). The mean fluorescence intensity of granulocyte CD18 was also increased by the above cytokines, whilst that of CD11b was only increased by TNF-β. Up-regulation of granulocyte CD18 expression was seen with 1 U/ml of IL-2, TNF-α or TNF-β, in contrast to the effect of IL-4 which was only observed with 100 U/ml. Similarly, enhanced expression of CD35 was induced by 1 U/ml of lL-2 or TNF-α but not by concentrations of IL-4 or TNF-β lower than 100 U/ml. Cytokine effects on the CD11/CD18 complex and CD35 molecules were not modified by cycloheximide, suggesting that their increased expression was not due simply to synthesis de novo. None of the granulocyte surface determinants investigated was altered upon short-term incubation of blood with either IL-1, IL-6 or interferon-gamma (IFN-γ). The demonstration in vitro that cytokines selectively up-regulate granulocyte integrins and complement receptor 1, suggests that similar mechanisms may be operating during the control of granulocyte-mediated inflammatory processes. [ABSTRACT FROM AUTHOR]

S-antigen, a potent retinal autoantigen involved in human inflammatory eye disease, has been chemically digested with cyanogen bromide to generate various peptide fragments. Cleavage of bovine S-antigen at methionyl residues generates seven major polypeptide fragments of apparent molecular weight 26,000, 22,000, 19,000, 18,000, 12,500, 8000 and 3000, respectively. Immunoblotting following SDS-polyacrylamide gel electrophoresis either with monoclonal antibodies known to be directed to two separate antigenic determinants on S-antigen or with various polyclonal antisera identified two peptide fragments of 26,000 and 18,000 MW. The extreme insolubility of the larger peptide fragments in aqueous or organic buffers makes the purification of the polypeptides by biochemical procedures difficult. However partial purification of the remaining soluble peptides by gel filtration in urea containing buffers made it possible to ascertain that the 18,000 MW peptide is an important constituent that carries a uveitogenic determinant of this autoantigen. [ABSTRACT FROM AUTHOR]

This paper describes the application of numerical methods to the arrangement of four leishmanial strains according to their reactivity and cross-reactivity in tests of parasite agglutination, indirect immunofluorescence and passive cutaneous anaphylaxis with antisera prepared by immunization or infection of rabbits, guinea-pigs and mice. Using corresponding pools of animal sera as test 'reagents' the antigenic reactivity of the four leishmanial strains (L. enriettii, L. tropica major, L. aethiopica and L. mexicana amazonensis) was scaled by reference to end point serum titres; and antigenic relationships between individual strain pairs were expressed as mean similarity coefficients, giving equal weight to the results of the different serological tests. Overall analysis of the results revealed that L. mexicana amazonensis and L. tropica major were the two most closely related strains, clustering with an overall similarity coefficient of 89 per cent, whereas coefficients of similarity between other strain combinations fell between 75 and 80 per cent. Although different sera had different discriminatory capacity for the leishmanial strains, two combinations of serum reagent and test system yielded relationships between the four strains that most closely approximated to the overall values. These were: (a) immunofluorescence tests with mouse antisera; and (b) agglutination tests with selected rabbit antisera. The results illustrate the use of a number of immunological parameters in relatingmicro organisms of a given genus, and reveal a serological classification of the four leishmanial strains at variance with their geographical origin. [ABSTRACT FROM AUTHOR]

Complement-fixing and precipitating antibodies to mitochondrial and lysosomal fractions of rat liver were induced in rabbits. The incubation of these subcellular fractions with ferritin-labelled antibody revealed localization of the antibody on mitochondria and lysosomes, but no specific morphological effect of antibody and complement. Incubation of the cell fractions with antibody and complement did not impair the efficiency of mitochondrial oxidative phosphorylation or affect the latency and sedimentation characteristics of lysosomal acid phosphatase. The results are discussed in relation to the action of antibody and complement on cells and to possible mechanisms of tissue damage in autoimmunity. [ABSTRACT FROM AUTHOR]

This communication describes the use of micro-electrophoresis in studying the changes in ascites tumour cells exposed to antibodies and complement. Treatment of the cells with rabbit antibody led to a change in electrophoretic mobility consistent with a surface adsorption of γ-globulin. The addition of complement led to a reduction in this electrophoretic effect of antibody. Treatment of the cells with neuraminidase, which produced a marked fall in their electrophoretic mobility, did not alter the effect of rabbit antibody and complement on the cells. Incubation with iso-antibody, in the presence or absence of complement, did not alter the mobility of the ascites cells measured at pH 7.0. The addition of 0.01 M calcium chloride to the electrophoresis medium produced a fall in mobility of the cells exposed to either antibody preparation in the presence of complement. Therefore, although iso-antibody and complement did not produce direct changes in cell mobility, changes in the cell surface could be detected by electrophoresis in the presence of calcium ions. The possibility is discussed that, during immune cytolysis, unmasking of phosphate groups of phospholipids might take place in the cell surface. [ABSTRACT FROM AUTHOR]

The injection of rat liver and rat brain in Freund's complete adjuvant into rabbits led to the production of complement fixing autoantibodies against rabbit tissue. The autoantibody response following the injection of rabbit liver and brain was much smaller. The autoantibody response to rat liver occurred even when Freund's incomplete adjuvant was used. The injection of rabbit liver in Freund's complete adjuvant into rabbits which had produced autoantibody after the injection of rat liver did not increase the level of autoantibody to rabbit liver. In most, but not all, rabbits the natural antibody found in the sera taken before immunization was destroyed by heating the sera at 65°. After immunization with rat liver in Freund's complete adjuvant the levels of serum antibody to rabbit liver stable at 56° rose by day 5; however, autoantibody stable at 65° was not detectable until between days 7 and 14. [ABSTRACT FROM AUTHOR]

Retinal S-antigen (S-ag), found in the rod photoreceptors of the eye, is a potent autoantigen that is commonly involved in inflammatory eye disease leading to blindness in man. Antibodies, induced in the experimental model by immunizing rats with S-ag purified from porcine retina, were used to prepare heterologous rabbit anti-idiotypic antibodies. The binding of the four rabbit anti-idiotypes to S-ag antibodies was partially inhibitable by porcine S-ag but not by ovalbumin. The idiotypic determinants were localized to the heavy chains by Western blotting with the anti-idiotypes. The presence of the idiotype recognized by the rabbit anti-idiotype was assessed in antisera from various species containing antibodies to S-ag. All rat sera from animals undergoing experimental autoimmune uveoretinitis by immunization with S-ag from porcine or bovine retina contained antibodies that react to varying degrees with the rabbit anti-idiotype. The intraspecies nature of the idiotypic determinants recognized was demonstrated by the fact that none of the anti-idiotypes showed any reactivity with rabbit or murine antisera to S-ag from porcine, bovine or human retina or to human autoantibodies to S-ag from patients with inflammatory eye disease. Thus, all private and recurrent idiotypic determinants induced in rats by immunization with S-ag appear to be restricted to that species.

This paper describes the application of parallel bioassay to determine the extent to which the leucocyte chemotactic activity of guinea-pig lymphokine preparations is associated with their lymphocyte mitogenic, inflammatory (increased vascular permeability) and macrophage migration inhibitory activities. A convenient test of chemotactic activity was devised whereby Coulter counter determinations were made of the number of peritoneal exudate cells passing through a Nuclepore membrane into the medium of the lower (test) compartment of a chemotaxis chamber. Symmetrical parallel line (2+2) dose assays were used to obtain potency ratio estimates of the chemotactic activity of seven lymphokine preparations whose mitogenic, inflammatory and migration inhibitory activities were already known. Statistical analysis of the results revealed a clear dissociation of chemotactic activity from mitogenic and migration inhibitory activities; but with six of the seven lymphokine preparations, a marked similarity was revealed between their chemotactic and inflammatory activities. Cytological studies showed that although the lymphokine preparations were chemotactic for different cell types, there was a preferential migration of neutrophils and the smaller mononuclear cells. The demonstration by parallel bioassay of an association between the ability of lymphokine preparations to increase vascular permeability in vivo and to promote chemotaxis of leucocytes in vitro is viewed in relation to the possible role of lymphokine in inflammatory processes.

This paper describes the application of numerical methods to the arrangement of four leishmanial strains according to their reactivity and cross-reactivity in tests of parasite agglutination, indirect immunofluorescence and passive cutaneous anaphylaxis with antisera prepared by immunization or infection of rabbits, guinea-pigs and mice. Using corresponding pools of animal sera as test 'reagents' the antigenic reactivity of the four leishmanial strains (L. enriettii, L. tropica major, L. aethiopica and L. mexicana amazonensis) was scaled by reference to end-point serum titres; and antigenic relationships between individual strain pairs were expressed as mean similarity coefficients, giving equal weight to the results of the different serological tests. Overall analysis of the results revealed that L. mexicana amazonensis and L. tropica major were the two most closely related strains, clustering with an overall similarity coefficient of 89%, whereas coefficients of similarity between other strain combinations fell between 75 and 80%. Although different sera had different discriminatory capacity for the leishmanial strains, two combinations of serum reagent and test system yielded relationships between the four strains that most closely approximated to the overall values. These were: (a) immunofluorescence tests with mouse antisera; and (b) agglutination tests with selected rabbit antisera. The results illustrate the use of a number of immunological parameters in relating micro-organisms of a given genus, and reveal a serological classification of the four leishmanial strains at variance with their geographical origin.