ISSN:0014-2980    

DOI:10.1002/eji.1830130802

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractA subclone of an IgM‐producing hybridoma has been identified which has switched to producing an IgG1antibody. The parent hybridoma, PC‐140, produces an antibody which binds phosphorylcholine and reacts with monoclonal antibodies that recognize myelomas of the T‐15 idiotype. The IgG1antibody binds phosphorylcholine with the same affinity as the parental IgM and also reacts with the anti‐T‐15 monoclonal antibodies. While the IgM‐producing parent hybridoma does not express detectable surface IgM, the IgG1‐producing subclone produces both membrane and

ISSN:0014-2980    

DOI:10.1002/eji.1830130803

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractThe ability of cultivated mouse peritoneal macrophages (MΦ) to release superoxide anion (O2−) after repeated stimulation by phorbol myristate acetate (PMA) or serumtreated zymosan (STZ) has been studied. After a maximal first stimulus bacillus Calmette‐Guérin (BCG)‐activated MΦ released high levels of O2−, 2‐fold more than thioglycollate‐elicited MΦ and the response ceased within 4 h. Both populations either responded again to a second challenge or displayed a refractory state which varied in duration and selectivity. Desensitization by STZ pretreatment was transient and selective whereas PMA could render MΦ refractory for 3 days to PMA alone or to both agents, depending on the amount of PMA used and the conditions of stimulation. PMA induced a selective loss of specific saturable receptors for [3H]phorbol dibutyrate, a closely related agent, and receptor activity recovered with the ability to release O2−. Loss of receptors did not account for concomitant loss of the response to STZ after nonselective deactivation. Such MΦ were fully viable and able to endocytose various soluble and particulate ligands vigorously, but without stimulation of the hexose monophosphate shunt or release of O2−.Our studies indicate that MΦ activities can be profoundly altered by prior stimulation, that specific receptors play a role in ligand‐induced desensitization and that agents such as PMA can selectively eliminate the cells′ ability to generate

ISSN:0014-2980    

DOI:10.1002/eji.1830130804

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractThe Peyer's patches (PP) of sheep have a number of important anatomical features and functional characteristics which are similar to tissues that have been classified as primary lymphoid organs. The prenatal maturation of PP occurs in the absence of any antigenic stimulus as immunogenic molecules are not normally encountered by the sheep fetus. Primordial PP were first detected in the small intestine of fetal sheep at about 60‐days gestation; lymphoid follicles were present by 75‐days gestation and vigorous lymphopoiesis was occurring in these follicles by 100 days. From 120‐days gestation until birth, at about 150 days, the PP follicles were histologically mature and they had the greatest density of proliferating lymphoid cells found anywhere in the body. The total number of PP and their constituent follicles had developed before birth when there were 25–40 discrete PP in the jejunum and proximal ileum and one single continuous PP in the terminal ileum. There was no evidence of any change in the rate of growth of the PP follicles at birth which could be related to the advent of the first antigens in the gut.The total weight of PP tissue was greater than any other single lymphoid tissue by about 6 weeks after birth weighing around 120 g or about 1.2% of the body weight; about 50–60 g of the PP tissue was calculated to be lymphoid tissue. At this time the ileocecal PP (IPP) extended 2.5 m along the terminal ileum and accounted for about 90% of the total mass of PP.From about 12 weeks after birth the IPP began to involute and only a few PP follicles remained in this region of the intestine by 18 months of age. Follicles in PP in other parts of the small intestine remained and continued to produce lymphocytes throughout the life of the animal.PP contain a number of anatomically and functionally distinct lymphoid compartments that could play different roles in the body's immune defense. Explicit in most theories on the function of PP is the notion that antigenic stimulation is the cause of the lymphopoiesis in the follicles; our results do not support this view. Instead they suggest that the follicles in the PP of sheep may play a role similar to that played by the bursa of Fabricius

ISSN:0014-2980    

DOI:10.1002/eji.1830130805

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractThe mechanism of synergistic complement‐mediated lysis of rat red cells was investigated using rat monoclonal antibodies against class IR1Aaantigens. The increased lytic activity when using two antibodies simultaneously is due to the increase in the number of activated C1 molecules on the cell surface and this results from (a) an increase in the number of binding sites for C1q, (b) an increase in the functional affinity constant for C1q binding and (c) an increase in the rate of activation of C1. Complete lysis of red cells was only achieved if one member of the synergistic pair was of the γ2bisotype, and this isotype weas the only one to which binding of125I‐labeled C1q could be detected. A partial synergistic effect was seen using an F(ab′)2fragment of antibody. Increased uptake and activation of C1 probably results both from the presence of two antibodies attached to each antigen molecule and from the formation of antigen‐antibody

ISSN:0014-2980    

DOI:10.1002/eji.1830130806

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractErythrocyte (E) rosette‐forming cells have been investigated in three patients with B chronic lymphocytic leukemia whose leukemic lymphocytes were easily identifiable. A small percentage of fresh neoplastic cells formed E rosettes in two patients. In every patient, most unstimulated, cultured leukemic lymphocytes became E+and this was further enhanced by phytohemagglutinin and pokeweed mitogen stimulation or neuraminidase treatment. These E+B cells lacked detectable T cell antigens (except for a weak expression of an antigen associated with the helper T cell subpopulation in one case). They were unreactive or weakly reactive by immunofluorescence with a monoclonal antibody to the E receptor. However, this antibody completely inhibited E‐rosette formation. The enhanced expression of E‐rosette receptors byin vitrocultured cells appeared to be dependent upon the presence of a small number of E‐rosetting cells at the beginning of the culture. E‐rosette receptor expression by leukemic lymphocytes was most likely in a fourth case (out of 9 patients studied). This finding may account for some of the discrepancies in the study of so‐called T cells in B chronic lymphocyt

ISSN:0014-2980    

DOI:10.1002/eji.1830130807

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractThe constitutive and lipopolysaccharide (LPS)‐induced secretion of interleukin 1 (IL1) by cultured human monocytes and macrophages has been studied. Both freshly obtained monocytes and their culture‐derived macrophages were induced by LPS to secrete similar amounts of IL1. Such induction, however, was accompanied by the secretion of dialyzed inhibitory activity. Constitutive secretion of IL1 was detected in concentrated supernatants of monocyte cultures. The factor obtained constitutively did not manifest significant inhibitory activity. A method is described for the recovery of IL1‐containing supernatants in serum‐ and other stimulant‐free medium. The biological activities of the constitutively secreted IL1 were similar to the LPS‐induced activities.The constitutive secretion of IL1 was not equally distributed in the entire monocyte population. We found that a small fraction of loosely adherent monocytes secreted higher amounts of IL1 than the strongly adherent monocytes. However, the property of higher secretion of IL1 was not stable and disappeared following monocyte cultivation. Thus, constitutive activity of IL1 could be recovered either by concentrating the culture supernatants or by enriching a subset of monocytes with higher I

ISSN:0014-2980    

DOI:10.1002/eji.1830130808

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractSpecific suppressor T cells (Ts) were inducedin vitroby incubation of mouse spleen/lymph node cells with allogeneic heat‐treated cells. These Ts inhibit mixed lymphocyte reaction (MLR) in a haplotype‐specific manner. Ts also suppress cell proliferation induced by third‐party H‐2 alloantigens provided these are expressed on the same cell surface as at least some of the H‐2 antigens used for Ts activation. Ts activated by H‐2 plus non‐H‐2 alloantigens suppress an MLR induced by irrelevant H‐2 alloantigens if these are expressed on the same cell surface as the non‐H‐2 alloantigens used for Ts activation. Products of the H‐2 region or non‐H‐2 alloantigens which are not able to stimulate cell proliferation do not activate Ts. These Ts are first demonstrable after 4 days of incubation of lymphoid cells with heat‐treated allogeneic cells and they inhibit MLR only if added at the very beginning of the culture. Exogenous interleukin 2 does not overcome suppression and the suppression is not due to a cytotoxic effect, since heat‐treated cells do not elicit cell proliferation or cytotoxic cells. Moreover, the specific Ts differ in their Thy‐1+,Ly‐1+,2−phenotype from Ly‐2+allospecific cytotoxic cells. Thus specific Ts could be inducedin vitro, which demonstrate linked suppression for third‐party H‐2 alloantigens provided these are expressed on the same cell sur

ISSN:0014-2980    

DOI:10.1002/eji.1830130809

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractSplenic T cells were primed, after removal of alloreactive cells, to beef insulin on allogeneic antigen‐presenting cells (APC). The fine specificity ofin vitrosecondary response was tested in combinations H‐2b(responder) T cell‐H‐2k(nonresponder) APC, andvice versa, using separated chains of beef and pork insulin. The response in both combinations exhibited identical specificity patterns demonstrating that both responder and nonresponder APC could present the same array of insulin epitopes to allogeneic T cells. The determinants presented to allogeneic T cells include the A‐chain loop epitope and the B‐chain determinant(s) that were found to be immunogenic for H‐2band H‐2dT cells, respectively, in the context of syngeneic major histocompatibility complex (HC) molecules. In addition, minor determinants were detected in the A chain outside the loop that are not immunogenic in syngeneic T cell‐APC combinations. Inhibition of T cell proliferation with monoclonal antibodies has shown that class II MHC molecules of the nonresponder (AαkAβk, EαkEβk) as well as those of the responder APC (AαbAβb) are equally capable of presenting virtually all insulin epitopes recognizable by T cells. The data, therefore, demonstrate that the selective recognition of different insulin epitopes observed in syngeneic or semisyngeneic T cell‐APC combinations does not result from determinant sele

ISSN:0014-2980    

DOI:10.1002/eji.1830130810

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractInterruption of the afferent lymphatic vessels of the popliteal lymph node resulted in the disappearance of high endothelial venules (HEV) and immigrating lymphocytes within 3 weeks. HEV showed several characteristic morphological changes: the endothelial cells became flattened and less pyroninophilic, the chromatine became condensed and protein synthetizing and secretory cell organelles became scarce. At the same time the number of macrophages in the lymph node was severely reduced. Injection of sheep red blood cells into such lymph nodes, 6 weeks after operation, resulted in reappearance of HEV and immigrating lymphocytes, and development of many plasma cells and some germinal centres. Injection of lipopolysaccharide into the operated lymph nodes resulted in the appearance of many plasma cells and a few poorly developed germinal centres; HEV and immigrating lymphocytes, however, remained almost absent.The results show a relationship between the immigration of lymphocytes and the activity of the endothelial cells in the HEV. The activation of the latter may occur by mediators released by antigen‐stimulated macrophages and T cells. Moreover, the morphological features of the HEV are independent of the presence of recirculating lymphocyte

ISSN:0014-2980    

DOI:10.1002/eji.1830130811

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY