摘要:

AbstractThe effects of polyinosinic, polycytidylic acid [poly(I) · poly(C)] on the activation and RNA metabolism in murine peritoneal macrophages (MΦ) elicited by proteose‐peptone (pMΦ) was investigated. Poly(I) · poly(C) triggered the cytolytic activity of pMΦ and augmented their glucose oxidation. In contrast, a profound depression of [3H]uridine incorporation into RNA was observed in poly(I) · poly(C)‐activated pMΦ. The degree of depression of RNA labeling paralleled the dose of poly(I) · poly(C) used to activate the pMΦ and the expression of tumoricidal activity. This decrease in [3H]uridine incorporation into MΦ RNA could not be accounted for by decreased permeability of the activated MΦ to [3H]uridine, or by instability of the labeled RNA. Moreover, analysis of the specific activity of the intracellular uridine triphosphate (UTP) pool and studies on the labeling of MΦ RNA with [32P] orthophosphate indicated that the decreased RNA labeling was not due to changes in the specific activity of UTP. We concluded that poly(I) · poly(C)‐activated pMΦ exhibit a depressed rate of RNA synthesis. We suggest that the rate of RNA synthesis may be investigated as a potential new indicato

ISSN:0014-2980    

DOI:10.1002/eji.1830131202

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractSupernatants containing interleukin 2 (IL2) induce strong proliferation and expression of natural killer (NK)‐like activity in human thymocytes. Different supernatants were compared for: (a) IL2 activity, (b) thymocyte proliferation capacity and (c) induction of NK‐like cytotoxicity. All these activities were present in a partially purified IL2 preparation obtained by gel filtration chromatography (Mr15000–20000). However, in supernatants from different sources and in the 15000–20000‐Mrsemipurified fractions, we observed that the NK‐like cytotoxicity inducer effect did not correlate with either the mitogenicity or the IL2 activity.The presence in the supernatants of interleukin 1 (IL1), interferon (IFN) or phytohemagglutinin (PHA) does not seem to be a prerequisite for the induction of NK‐like cytotoxicity, since this activity was (a) fully present in supernatants devoid of IL1, IFN and PHA, (b) absent in preparations of IL1 and (c) not augmented after supplementation of the supernatants with IFN‐γ.We also investigated the cellular characteristics of the precursor thymocytes responsive to IL2 supernatants. Removal of the T3+cells at the initiation of the culture abrogated the proliferative response and eliminated the generation of NK‐like cytotoxicity. Under the same conditions, removal of the HTA1+population increased the proliferation and did not affect the NK‐like activity.Our results suggest that: (a) either IL2 is not responsible for the induction of NK‐like cytotoxicity or its action is modulated by other molecules, and (b) the precursor‐responder population is preferentially included

ISSN:0014-2980    

DOI:10.1002/eji.1830131203

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractIn a model system for accessory cell (AC)‐dependent mitogen‐induced T cell proliferation the response of several human antigen‐specific, HLA‐restricted helper T lymphocyte clones (HTLC) to mitogens was studied. It was found that the HTLC themselves did not or only weakly respond to various mitogens or to oxidation by galactose oxidase, but that the response could be strongly increased if certain tumor cell lines were added to the assay as AC. Pretreatment with lectins or oxidation of either HTLC or AC was effective in stimulating the proliferation of the T cells in this system. Reduction of the aldehydes formed during oxidation completely abolished the stimulatory activity of oxidized B lymphoblastoid cell line. This shows that crosslinking of T cell and AC is required to induce proliferation.When several established cell lines were tested for their capacity to function as AC in this system, profound differences in AC activity were detected. The inability of cells with poor AC activity to stimulate the HTLC was not due to trivial reasons, such as requirements for different mitogen concentrations, a decreased binding of mitogens or suppressive effects. Furthermore, AC activity was not dependent on the presence of Ia antigens on the AC. These findings are discussed with regard to the mechanism of mitogen‐induced T cell a

ISSN:0014-2980    

DOI:10.1002/eji.1830131204

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractIn response to concanavalin A (Con A) mouse spleen cells produce increased amounts of urea. This increase results from arginase activity degrading arginine into urea and ornithine. It is mediated by a soluble protein factor, characterized by its heat stability (10 min at 80°C) and a molecular weight of approximately 32000. The factor is produced by T cells and acts on a cell population mainly present in bone marrow and spleen. Splenocytes collected from skin allograft recipients during rejection produce more urea in response to Con A than those obtained from normal or syngeneically grafted mice. The maximum urea increase is observed just before and maintained during rejection, declining rapidly thereafter. This phenomenon is explained (a) by a 10–15‐fold increase in arginase‐enhancing factor production by Con A‐stimulated allograft recipient spleen cells and (b) by an increased responsiveness of these splenocytes to the ly

ISSN:0014-2980    

DOI:10.1002/eji.1830131205

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractIn this study the antigen‐presenting functions of murine splenic dendritic cells (DC) and macrophages (MΦ) have been compared. DC and MΦ were pulsed with keyhole limpet hemocyanin (KLH) and found to contain approximately 92% and 50% Ia‐positive cells, respectively. The two KLH‐pulsed cell populations had almost equal ability to stimulate KLH‐immune T cells. The antigen‐presenting functions of DC and MΦ were compared by measuring the capacity of KLH‐pulsed, UV‐irradiated cells, which failed to secrete interleukin 1 (IL1), to stimulate KLH‐immune T cells when each culture was supplemented with an equal amount of exogenous IL1. The antigen‐presenting capacity of DC was always greater than that of MΦ. Coculturing of the two kinds of accessory cells upon KLH pulsing resulted in enhanced antigen‐presenting capacity of the mixture relative to the same number of each accessory cell type. That is, collaboration between them in antigen presentation was clearly observed. However, direct contact between DC and MΦ was not obligatory for this collaboration. Furthermore, we found that different types of soluble factors released by each of them might be responsible for the collaboration. In addition, supernatants of concanavalin A‐stimulated spleen cells augmented the antigen‐presenting function of only MΦ. Finally, the antigen‐presenting function of DC and MΦ from athymic mice was almost th

ISSN:0014-2980    

DOI:10.1002/eji.1830131206

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractMembrane‐bound IgG was found only on old populations of platelets from normal individuals. This IgG could be dissociated from senescent cells by repeatedly heating the cells. Heat‐eluted IgG (He‐IgG) prepared from senescent red blood cells was capable of binding to either heat‐treated old platelets orVibrio choleareneuraminidase (VCN)‐treated young platelets, suggesting expression of a common age‐dependent antigen on the senescent red blood cells and old platelets. We analyzed the role of membrane‐bound IgG in the immune elimination of aging platelets by direct phagocytosis of different platelet subpopulations by autologous monocytesin vitro.While removal of He‐IgG from old platelets inhibited their phagocytosis, preincubation of either heat‐treated old or VCN‐treated young platelets promoted phagocytosis of these cells by autologous monocytes. The phagocytosis of senescent cells required intact IgG on these cells. Either removal of Fc fragments from He‐IgG or treatment of autologous monocytes with Fc fragments prior to the phagocytosis assay resulted in a marked reduction of phagocytosis (>75%). We conclude that Fc receptors on the monocytes and the presence of membrane‐specific IgG are crucial elements for immune elimination

ISSN:0014-2980    

DOI:10.1002/eji.1830131207

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractFollowing i.p. injection of ovalbumin (OVA) plusBordetella pertussisvaccine into Hooded Lister rats, the time‐course of sensitization of peritoneal and lung mast cells (MC) did not parallel kinetic changes in the levels of circulating OVA‐specific and total IgE. OVA‐induced secretion of 5‐hydroxytryptamine from isolated peritoneal and lung MC and the presence of OVA‐specific IgE in serum were first demonstrated at day 14 post‐immunization. However, subsequent to day 14, the responsiveness of both types of MC to OVA declined, while circulating levels of OVA‐specific IgE continued to rise. Peritoneal MC, but not lung MC, showed increased responsiveness to challenge with anti‐IgE on day 7 post‐immunization, whereas circulating levels of total IgE were not elevated until day 14, thus demonstrating that nonantigen‐specific IgE was acquired by peritoneal MC before it entered the circulation. Lung MC generally showed decreased reactivity to both OVA and anti‐IgE, compared with peritoneal MC; no significant correlations were demonstrated between the responses of MC from t

ISSN:0014-2980    

DOI:10.1002/eji.1830131208

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractThe MOPC460 idiotype is expressed in mice with the IghCaallotypic haplotype after anti‐2,4‐dinitrophenyl (DNP) immunization. We have previously shown that two monoclonal syngeneic anti‐idiotypic antibodies (IDM 92‐13 and IDM 41‐27) define two distinct idiotopes (the 460.92 and the 460.41) on the M460 idiotype. The current study demonstrates that only one idiotope (460.92) is recurrently expressed after antigen immunization in IghCapositive mice and also that, immunization against the monoclonal anti‐idiotypic molecules induces the synthesis of 460.92 idiotope positive anti‐DNP antibodies. However, the detection of such molecules is only possible when animals with the IghCaallotypic haplotype are immunized with the IDM 92‐13 molecules. Immunization of mice with either of the two monoclonal anti‐idiotypic antibodies never results in the synthesis 460.41 positive molecules. Therefore, whatever protocol of immunization used, the expression of 460.92 was all

ISSN:0014-2980    

DOI:10.1002/eji.1830131209

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractThe existence of disulfide‐bonded immunoglobulin (Ig) complexes of IgM‐IgA, IgM‐IgG, and IgM‐IgG, in addition to a monoclonal IgM (x) paraprotein, free kappa chains and fragments of IgG (FIgG), were found in the plasma of a multiple gammopathy patient. This is the first report on the interclass disulfide‐bonded Ig complexes. Upon exposure to a dissociating buffer containing 6Murea, 0.1MTris‐HCl, pH 8.0, a small portion of the IgM‐IgA complexes and most of the IgM‐IgG as well as the IgM‐FIgG complexes dissociated, but the majority of the IgM‐IgA and small amounts of other complexes remained intact. These intact complexes were not the result of antigen‐antibody reactions and were apparently held together by disulfide bonds which could be broken into monomeric Ig basic units (H‐L)2and smaller components by mild r

ISSN:0014-2980    

DOI:10.1002/eji.1830131210

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractHybrids formed between human acute lymphoblastic leukemia (ALL) cells and mouse myeloma have been used to determine the chromosomal location of genes required for the expression of several monoclonal antibody (mAb)‐defined cell surface antigens on ALL cells. Cloned hybrids were tested for antibody binding, immunoprecipitation of the relevant protein, chromosome isoenzyme markers and karyotype. Two antigens of those studied could be definitively mapped, OKT10/p45 to chromosome 4 and BA‐2/p24 to chromosome 12. mAb BA‐2 reacts with the same protein as another mAb designated 609‐29 (anti‐teratocarcinoma). Reactivity with the latter mAb has been previously shown to segregate with chro

ISSN:0014-2980    

DOI:10.1002/eji.1830131211

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY