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51.
A. KIJLSTRA D. W. KNUTSON M. R. DAHA L. A. VAN ES 《Scandinavian journal of immunology》1979,10(5):421-429
The in vivo behaviour of well-defined immune complexes in rats was studied using complexes derived from DNP-conjugated bovine thyroglobulin (DNP-BTG) and purified specific goat anti-DNP IgG. Both clearance and glomerular localization were mainly dependent on the nature of the antigen. Soluble immune complexes formed with DNP17-BTG were cleared faster and showed a more marked localization in the glomerular mesangium than complexes formed with DNP3.4-BTG. A slight increase in the antibody to antigen ratio seemed to facilitate mesangial localization of soluble immune complexes. Insoluble immune complexes showed temporary localization as microemboli in the lumina of glomerular and peritubular capillaries. This study thus shows that not only the size and composition of the complexes but also the nature of the antigen within the complex can influence the clearance and organ localization of circulating immune complexes. 相似文献
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Analysis of antigen specific T cell helper function in first degree relatives of patients with systemic lupus erythematosus (SLE). 下载免费PDF全文
R Segal C Brautbar D Katz Y Shalev Z Bentwich E Mozes 《Clinical and experimental immunology》1986,66(1):52-60
Fourteen families with first degree relatives of patients with systemic lupus erythematosus (SLE) were studied for the ability of their members to respond to the synthetic polypeptide antigen (T,G)-A-L. The family members were also tested for their HLA determinants. All SLE patients tested responded to (T,G)-A-L as measured by the production of (T,G)-A-L specific T cell helper factors by their antigen activated T cells, confirming our previous findings that 100% of SLE donors responded to (T,G)-A-L in contrast to 50% responders in a control population of healthy donors. The general defect in the regulation of immune responses in SLE patients was further indicated by the demonstration that an SLE patient who is a daughter of non-responder parents to (T,G)-A-L, responded to this genetically regulated antigen. In contrast to our observations with SLE patients, the genetic regulation of the ability to respond to (T,G)-A-L was shown not to be impaired in healthy first degree family members of SLE patients and the segregation of the immune response potential in these families was as expected from an inherited dominant trait. 相似文献
55.
Evolutionary conservation of brain Thy-1 glycoprotein in vertebrates and invertebrates 总被引:1,自引:0,他引:1
The evolutionary conservation of brain Thy-1 glycoprotein in 24 vertebrate and invertebrate species has been investigated by means of a soluble phase radioimmunoassay (RIA) and by the "Western blot" technique. The brain glycoproteins from virtually all the vertebrate species inhibited the precipitation of mouse Thy-1.1 by a rabbit anti-rat Thy-1 antiserum. Most reagents also inhibited the binding of a mouse anti-rat Thy-1 monoclonal antibody to rat Thy-1. Whole tissue glycoproteins from earthworm, snail and oyster and ganglia glycoproteins of a locust species were also found to be inhibitory. Western blotting analysis on NaDod SO4 polyacrylamide gel electrophoresis under reducing conditions revealed a Thy-1 homologous molecule (22-25 KD) in mammals, birds, fish, reptiles and invertebrate species. The snail Thy-1-like molecule was eluted from the gel and was shown to specifically inhibit the serological reaction. The rabbit anti-rat Thy-1 antiserum also detected a doublet molecule of approximately 85,000 KD, which is conserved in all species, including yeast and bacteria. The origin and nature of the presumed glycoproteins is unknown. Our results suggest that the Thy-1 molecule has been conserved throughout metazoan evolution and that the Thy-1 gene is the most conserved among the immune related genes (immunoglobulins, beta 2-microglobulin and major histocompatibility) which share extensive amino acid homology. 相似文献
56.
R. Michael Sly John A. Anderson C. Warren Bierman Paul Chervinsky Frederick C. Cogen James G. Easton Israel Glazer James P. Kemp Allan Knight Richard A. Krumholz Richard A. Nicklas Burton M. Rudolph Diane E. Schuller Allen T. Segal R. Michael Sly Stanley J. Szefler Michael J. Welch Ned J. Whitcomb Minoru Yamate 《The Journal of allergy and clinical immunology》1985,75(4):443-449
57.
This article presents an integrated conception of the self based on cognitive and interpersonal theories. Implications for clinical practice are outlined, which include understanding the therapeutic relationship as a laboratory and change as involving self-expansion. Implications for clinical research are also presented and exemplified by two strategies, which are demonstrated in a single case study of a patient who successfully underwent a brief-term treatment. The first involves the use of Interpersonal Scenarios, which are structured idiographic vignettes scaled on several parameters, to measure change between psychotherapy sessions. The second involves the use of the Structural Analysis of Social Behavior, a measure of interpersonal process, and the Experiencing Scale, a measure of emotional involvement, to measure change within a session. 相似文献
58.
A mouse model of galactose-induced cataracts 总被引:4,自引:0,他引:4
Ai Y Zheng Z O'Brien-Jenkins A Bernard DJ Wynshaw-Boris T Ning C Reynolds R Segal S Huang K Stambolian D 《Human molecular genetics》2000,9(12):1821-1827
Galactokinase (GK; EC 2.7.1.6) is the first enzyme in the metabolism of galactose. In humans, GK deficiency results in congenital cataracts due to an accumulation of galactitol within the lens. In an attempt to make a galactosemic animal model, we cloned the mouse GK gene (Glk1) and disrupted it by gene targeting. As expected, galactose was very poorly metabolized in GK-deficient mice. In addition, both galactose and galactitol accumulated in tissues of GK-deficient mice. Surprisingly, the GK-deficient animals did not form cataracts even when fed a high galactose diet. However, the introduction of a human aldose reductase transgene into a GK-deficient background resulted in cataract formation within the first postnatal day. This mouse represents the first mouse model for congenital galactosemic cataract. 相似文献
59.
G R Irwin A M Allen H E Segal M Willhight H Cannon F H Top Jr 《Journal of clinical microbiology》1976,3(5):465-468
Sera from military personnel found to have antibodies to hepatitis B surface antigen (anti-HBS) in an epidemiological study of a hepatitis B outbreak were tested for persistence of that antibody 1 year later. Initially, 64% of the anti-HBS-positive sera reacted in passive hemagglutination tests with erythrocytes coated with hepatitis B surface antigen of both ayw and adw subtypes; the remaining sera reacted only with adw-coated erythrocytes (19%) or ayw-coated erythrocytes (17%). After 1 year, anti-HBS was detectable by passive hemagglutination tests in 87% of individuals with initial antibody to both subtypes but in only 41% and 16% (P less than 0.001) of those initially reacting only to adw- or ayw-coated erythrocytes, respectively. Seropositivity for anti-HBS correlated best with history of contact with jaundiced people (20.3%) and duty in Asia. 相似文献
60.
In the present study we have demonstrated that fibroblasts can generate the inflammatory cytokine interleukin 1 (IL 1) under conditions similar to those abundant in cellular immune responses. Thus, induction of IL 1 requires a sequential two-step protocol which consists of preactivation of mouse embryo fibroblasts (MEF) with crude preparations of T cell or macrophage-derived conditioned media (CM; 72 h), followed by a challenge with lipopolysaccharide (LPS; 24 h). Unstimulated fibroblasts or such cells activated by either CM or LPS produced only low levels of IL 1, while a synergism between both signals was observed for obtaining maximal IL 1-like activity in MEF. Each of a series of individual recombinant lymphokines and cytokines (IL 2, granulocyte/macrophage-colony-stimulating factor, tumor necrosis factor, IL 1 beta and interferons-alpha, beta and gamma) was shown to serve as an efficient priming signal for the induction of IL 1. IL 1-like activity in fibroblasts was detected in cell lysates or associated with the producing-cell membrane but not in culture fluids. Immune-stimulated fibroblasts, activated under such experimental conditions, were shown to actively transcribe mRNA of both IL 1 genes (alpha and beta). For the expression of IL 1-specific mRNA in fibroblasts a single stimulus, provided by either LPS or a lymphokine/cytokine, was sufficient; however, a more intense signal was observed when both stimuli were applied. The IL 1-like biological activity of fibroblast origin was significantly reduced by anti-IL 1 alpha antibodies. Thus, fibroblasts, when activated by immune and bacterial products, generate IL 1 which in turn possibly amplifies cellular immune responses or inflammatory processes in connective tissues. 相似文献