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181.
Dr. G. Sieber F. Herrmann B. Enders H. Rühl 《Journal of molecular medicine (Berlin, Germany)》1982,60(20):1303-1309
Summary Using a reverse hemolytic protein A plaque assay, spontaneous and pokeweed mitogen (PWM)-induced immunoglobulin (Ig) secretion was determined in peripheral blood from 22 patients with B1-chronic lymphocytic leukemia (CLL), one patient with B2-CLL, and one patient with suppressor T-CLL. Diagnoses were established by cytological and histological criteria as well as several marker analyses. Lymphocytes from B1- and B2-CLL patients were unable to secrete Ig either spontaneously or after PWM stimulation. In T-CLL lymphocytes, spontaneous Ig secretion was suppressed very probably by the OKT-8-positive leukemic population, since, after cultivation with PWM, a normal Ig secretion could be demonstrated which was paralleled by a decrease in the OKT-8-positive cells. Cocultivation experiments with freshly isolated, unseparated lymphocytes from normal subjects and lymphocytes from patients were of no informational value, since isolated normal B-cells alone already showed a high rate of Ig secretion. However, coculture experiments with separated subpopulations after PWM stimulation revealed an intrinsic B-cell defect in lymphocytes from B1-CLL patients, whereas their T-lymphocytes were found to be normal helper cells.
Abbreviations CLL Chronic lymphocytic leukemia - PWM Pokeweed mitogen - ISC Immunoglobulin-secreting cells - Ig Immunoglobulin(s) Supported by the Deutsche Forschungsgemeinschaft (Ru 215/2) 相似文献
Abbreviations CLL Chronic lymphocytic leukemia - PWM Pokeweed mitogen - ISC Immunoglobulin-secreting cells - Ig Immunoglobulin(s) Supported by the Deutsche Forschungsgemeinschaft (Ru 215/2) 相似文献
182.
L.?Yu.?Semenova Zh.?M.?Salmasi A.?N.?Kazimirskii G.?V.?PoryadinEmail author 《Bulletin of experimental biology and medicine》2004,138(7):65-66
Taban-Arshan extract decreased expression of T-lymphocyte activation markers, normalized T-cell-mediated immunity, and suppressed
increased activity of natural killer receptors during culturing with lymphocytes of patients with atopic bronchial asthma.
Taban-Arshan extract normalized activation processes in the B-cell immunity and stimulated expression of receptors of activation-induced
apoptosis.
Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 138, No. 7, pp. 76–78, July, 2004 相似文献
183.
184.
Xiaoyan Tang Sadaaki Hori R. Yoshiyuki Osamura Yutaka Tsutsumi 《Pathology international》1995,45(1):34-44
Extensive immunohistochemical analyses of the hyperplastic human palatine tonsil disclosed variegated B cell phenotypes on the lymphoid cells among the crypt epithelium. The reticular epithelial network was evident by cytokeratin immunostaining. The reticular epithelium near the crypt Iumen was positive for Iysozyme. Secretory component was negative, while HLA-DR was frequently expressed. Intramucosal small Iymphocytes, densely distributed in the Iuminal side, consisted mainly of B cells expressing CD19, CD20, CD21, CD22, CD45R, CD74, DBB42, HLA-DR, HLA-DQ, bcl-2 protein and surface lgM. Some B cells revealed mantle zone phenotypes (surface IgD+, CD5+, CD24+, DBA44+, CD10- -, DNA7- -). Cells of germinocyte phenotype (CD10+, DNA7+) were sparsely seen. A good number of intramucosal lymphoid cells were further labeled for CD11b, a phenotype of so-called B-1 cells. Plasma cells were clustered within the basal half. IgG was their major immunoglobulin class, followed by IgA, IgM and lgD classes. A smaller number of T cells (CD2+, CD3+, CD5+, CD45RO+, TCR αβ+) were identified among the epithelium. CD4+ cells predominated over CD8+ cells. TCR γΔ + cells were rare. Macrophages (CD68+), dendritic histio-cytes (S-100 protein+, CD1+), and natural killer cells (CD16+ or CD57+) were also dispersed. Another unique feature of this lymphoepithelial complex was the existence of HLA-DR intramucosal microvasculature, where lymphocyte recirculation was suggested. Proliferating cell nuclear antigen was detected commonly in the epithelial cells but rarely in the lymphoid cells. Possible lymphoepithelial interactions and morphologic similarities to the thymic medulla are discussed. 相似文献
185.
Melanoma antigen recognition by tumour-infiltrating T lymphocytes (TIL): effect of differential expression of melan-A/MART-1 下载免费PDF全文
Ramirez-Montagut T Andrews DM Ihara A Pervaiz S Pandolfi F Van Den Elsen PJ Waitkus R Boyle LA Hishii M Kurnick JT 《Clinical and experimental immunology》2000,119(1):11-18
We have isolated, from an individual patient with metastatic melanoma, a series of eight TIL clones capable of lysing autologous melanoma cell targets. Six of the eight clones expressed TCRAV2S1 and lysed targets expressing HLA-A2 and the Melan-A/MART-1 peptide: AAGIGILTV. Polymerase chain reaction-single stranded conformational polymorphism (PCR-SSCP) analysis showed that the Melan-A/MART-1-specific clones were predominant in the bulk culture prior to cloning. However, the tumour progressed in vivo even in the presence of these tumour cell-lytic clones. Using the anti-Melan-A/MART-1 MoAb (A-103), we noted that Melan-A/MART-1 expression on three melanoma cell lines varied considerably during in vitro culture, in the absence of T cell immunoselection, relative to cell density. Tumour cells which spontaneously decreased Melan-A/MART-1 expression were less susceptible to specific TIL lysis. Melan-A/MART-1 expression and susceptibility to lysis increased in cells cultured at lower density. These data suggest that modulation of tumour antigen may account for tumour progression in the presence of tumour cell-lytic T lymphocytes. The observations suggest a possible explanation for the common finding of Melan-A/MART-1-specific lytic TIL in clinically progressing melanomas, as well as a possible pathway for therapeutic intervention. 相似文献
186.
Differential expression of CD22 (Lyb8) on murine B cells 总被引:2,自引:0,他引:2
Erickson Loren D.; Tygrett Lorraine T.; Bhatia Sudershan K.; Grabstein Kenneth H.; Waldschmidt Thomas J. 《International immunology》1996,8(7):1121-1129
Previous studies have established the distribution, biochemistryand functional attributes of human CD22, a B cell-restrictedglycoprotein. Recently, molecular cloning of the murine CD22equivalent revealed this molecule to be the same as the previouslydescribed Lyb8 alloantigen. Using the anti-Lyb8 mAb Cy34.1.2,the present report documents the expression patterns of CD22within the murine B cell compartment. The results demonstratethat in the bone marrow, murine CD22 is absent on the surfaceof pro-B cells, pre-B cells and newly emerging lgM+ B cells.CD22 is present at a low density on immature IgMhi B cells andfully expressed on mature recirculating B cells. In the periphery,murine CD22 is expressed at mature levels on all B cell subsetsincluding follicular, marginal zone, B1 and switched B cells.Further studies showed CD22 to be retained on activated murineB cells for extended periods. Finally, in combination with CD23and heat stable antigen, CD22 can be used to delineate the immaturesplenic B cells, and distinguish them from follicular and marginalzone cells. Together, the results demonstrate murine CD22 tobe a useful pan marker for all mature B cell subsets. 相似文献
187.
D. J. Schendel Ralph Oberneder Christine S. Falk Petra Jantzer Susanne Kressenstein Barbara Maget Alfons Hofstetter Gert Riethmüller Elfriede Nößner 《Journal of molecular medicine (Berlin, Germany)》1997,75(6):400-413
Renal cell carcinomas belong to the small group of tumors that are able to induce antitumor responses. Here we describe two
general types of cytotoxic effector lymphocytes that can eliminate autologous tumor cells and discuss the role that major
histocompatibility complex encoded molecules play in governing their specificities. Improved understanding of the cellular
and molecular basis of renal cell carcinoma recognition opens new avenues of research with the potential to develop better
immunotherapies for patients with metastatic disease.
Received: 24 July 1996 / Accepted: 1 November 1996 相似文献
188.
During the past 10 years knowledge about the interactions between major histocompatibility complex (MHC) class I molecules
and the T-cell receptor (TCR) complex of cytotoxic T-cells (CTL) has developed dramatically. But the primary interest, both
with respect to structure as well as function, has concentrated on HLA-A and -B molecules because of their high sequence polymorphism
and their dominating presence at the cell surface. In contrast, HLA-C molecules seemed to be of only minor importance in the
cascade of immune reactions owing to their more limited polymorphism and reduced levels of surface expression. The inability
to define a number of antigen specificities had the result that HLA-C molecules were often neglected in studies of immune
response, transplantation, and disease association. More recently a new function has been identified for HLA class I molecules
where they act as inhibitors of the lytic capacity of natural killer (NK) cells and non-MHC-restricted T-cells. Moreover,
the understanding of this novel mode of negative regulation of cytotoxicity was remarkably influenced by HLA-C since these
were the first HLA class I molecules found to have such inhibitory potential. With this new inhibitory function serving as
an essential component of the immune system, HLA-C molecules can no longer be neglected. 相似文献
189.
M. A. Frolova V. Tregerova L. A. Bol'shukhina 《Bulletin of experimental biology and medicine》1978,85(6):770-773
The quantitative and qualitative composition of the leukocytes and dehydrogenase activity of the lymphocytes were determined in blood entering and leaving the transplanted heart at different times after grafting in dogs. A decrease in the lymphocyte count in blood flowing from the grafted heart was found, on account of retention of the lymphocytes in the graft; the activities of the mitochondrial dehydrogenases also were reversed as the result of contact of the lymphocytes with the foreign antigens of the transplanted heart. It is suggested that the mechanism of reversal is connected with the functions of the lymphocytes as immunocompetent cells.A. N. Bakulev Institute of Cardiovascular Surgery, Academy of Medical Sciences of the USSR, Moscow. Institute of Experimental Surgery, Slovak Academy of Sciences, Bratislava, Czechoslovakia. (Presented by Academician of the Academy of Medical Sciences of the USSR, P. A. Vershilova.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 6, pp. 704–708, June, 1978. 相似文献
190.
Savitskii VP Zorin VP Potapnev MP Potapenko AY 《Bulletin of experimental biology and medicine》2004,138(2):158-162
We studied accumulation of porphyrin photosensitizers chlorine e6, hematoporphyrin, and their derivatives by different lymphocyte subpopulations. The intensity of staining of B lymphocytes and natural killer cells with photosensitizers was higher compared to T lymphocytes. T cell subpopulation differed by their ability to bind photosensitizers. Relative accumulation of dimethyl esters of chlorine e6 and hematoporphyrin in cells surpassed that of nonesterified porphyrins. 相似文献