摘要:

AbstractHuman adherent monocytes were incubated with interferon (IFN) preparations, then washed and stimulated with endotoxins. The interleukin (IL1) activity in the supernatants of IFN‐treated monocyte cultures was found to be increased as compared to control (not pretreated) cultures. This phenomenon was observed whether α or β IFN was used, and was completely abolished by antiserum to the relevant IFN. IL1 secretion of IFN‐treated monocyte cultures could be triggered by suboptimal dosis of endotoxins, unable to induce any IL1 activity in control medium‐treated cultures. IFN was highly efficient in this system, since very low concentrations (of the order of 2 units) were effective. Since IFN alone, without endotoxin stimulation, was unable to induce IL1 secretion, the results indicate that IFN is able to activate monocytes, by inducing a potential secretory capacity rather than an ongoing IL1 secretion function. The ability of IFN to enhance the IL1 secretory potential of human monocytes may be relevant to the known immunoenhancing effects of IFN preparations and to the pyrogenic effects of IFN administration in p

ISSN:0014-2980    

DOI:10.1002/eji.1830130602

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractDirect binding of125I‐labeled rabbit anti‐NPbidiotype antibodies (RaId) was used to quantitate the expression by immune spleen and thymus cells of NPbId, the characteristic Id of the λ1‐containing antibodies made by C57BL/6 (B6) mice to the (4‐hydroxy‐3‐nitrophenyl)acetyl (NP) group. Direct binding of RaId by B and T cell preparations reached a maximum of 12 ng RaId per 108cells at 7 days after immunization. Spleen T cell preparations maintained similar levels of binding after positive selection for Thy‐1.2+cells and overnight culture. RaId binding was also demonstrated for immune B6 thymus cells and for spleen and thymus cells of immune SJL mice, which have the appropriate heavy chain allotype for NPbId expression but have only barely detectable serum Id. However, the NPbId of T and B cell preparations were indistinguishable by (a) the susceptibility of RaId binding by the cells to inhibition by hapten or by antibodies to the variable regions of λ light chains (anti‐Vλ) and by (b) the ability of anti‐Vλand of monoclonal antibodies to the constant region of λ1 chains (anti‐Cλ1) to immunoprecipitate antigen (NP10‐bovine serum albumin)‐binding proteins from detergent extracts of isotopically labeled cells. The results strongly imply that virtually all of the NPbId of T cell preparations is due to conventional NPbId antibody that is tightly bound to T cells. The results do not, however, exclude the possibility that the T cell preparations contain a trace amount (≤ 1 ng/108cells) of unusual NPbId‐

ISSN:0014-2980    

DOI:10.1002/eji.1830130603

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractLymphocyte precursors in bursa of Fabricius, thymus and bone marrow (BM) of chick embryos were studied at different stages of incubation over 12–21 days, and for their state of commitment to B or T cell lines of development. Cell suspensions were fractionated on albumin gradients to remove nonlymphoid cells and incubatedin vitrowith bursopoietin, a specific inducer of B cells, or crude chicken thymus extract, a specific inducer of T cells, or ubiquitin, a nonspecific inducer. Precursors were identified by increases in numbers of cells bearing surface alloantigens as determined by immunofluorescence, either Bu‐1 (specific to B cells) or Th‐1 (specific to T cells). Precursors inducible to Bu‐1+cells were found in bursal cells and BM cells from all age groups but not in thymic cells. Precursors inducible to Th‐1+cells were found in thymic preparations and BM cells at all ages, but in significant numbers in bursa on day 12 only. Because B and T precursors were never found together in bursa or thymus, or only in very unequal amounts, it was concluded that precursors in these organs were not multipotential but were separately committed to one or other line of development. This argument did not apply to BM cells, for which other evidence was obtained. Bu‐1+cells were specifically induced in BM cells with bursopoietin and then removed by complement‐dependent cytolysis with anti‐Bu‐1 antiserum. When the remaining cells were incubated with ubiquitin, only Th‐1+cells were induced, showing that Bu‐1 and Th‐1 precursors were separately committed. Surface IgM was never induced on either bursal or BM lymphocytes. The Ia (or B‐L) antigen was inducible on 12‐ to 21‐day bursal cells, but could not be generated on BM cells until day 14 onwards. The pattern of occurrence of committed lymphocyte precursors in the developing chick embryo suggests that these cells are released into the circulation from both central lymphoid organs at their respective times of high lymphopoietic activity, and accumulate in the BM at least up to the time of hatching. Moreover, the presence of committed B precursors in bursa and committed T precursors in thymus at times and in quantities appropriate to the known features of avian lymphopoiesis leads us to conclude thatin vitroinduction is analogous to a true stage ofin viv

ISSN:0014-2980    

DOI:10.1002/eji.1830130604

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractMRL/Mp‐lpr/lpr(MRL‐lpr) mice develop a generalized lymphadenopathy reflecting the expansion of a Lyt‐2−T cell population. The present report describes the pattern of reactivity of a xenogeneic monoclonal antibody (mAb 100C5) directed against this T cell population. By single‐ and two‐color flow cytofluorometry analysis this mAb was found to stain brightly 80–90% of T cells in enlarged MRL‐lpr lymph nodes. In contrast lymph node T cells from congenic MRL‐MP‐+/+ (MRL‐+) mice were either unstained (70%) or weakly stained (30%), these latter cells being mostly Lyt‐2+. Unexpectedly, all lymph node B cells from MRL‐+ or MRL‐lpr mice were as strongly 100C5+as MRL‐lpr T cells. Similar observations were made in C57BL/6‐lpr/lprand C57BL/6‐+/+ mice. Molecular weight determination suggested that the 100C5 mAb binds to the same molecule (Mr= 220000) on M

ISSN:0014-2980    

DOI:10.1002/eji.1830130605

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractAmong lectins fromLotus tetragonolobus, Ulex europaeus IandEvonymus europaea, agglutinating cells with blood group H determinants containingL‐fucose α1→2‐linked to subterminalD‐galactose, only the last lectin agglutinates thioglycolate‐ and paraffin oil‐stimulated murine and guinea pig peritoneal exudate cells (PEC). The agglutination is inhibited by specific inhibitors of Evonymus lectin only: lacto‐N‐fucopentaose I and lactose. These results suggest the presence of a determinant on the surface of PEC, containingL‐fucose α1‐linked at the nonreducing end which is different from blood group H determinants. Nonstimulated murine peritoneal cells (PC) are not agglutinated by the lectin but become agglutinable after neuraminidase treatment. Unstimulated guinea pig PC from different animals are agglutinated to a different extent by the same lectin concentration and show increased agglutinability after neuraminidase digestion. These results show that receptor for Evonymus lectin also exists on the nonstimulated PC but access to it is hindered by sialic acid. Trypsin‐ and pronase‐digested PEC show increased agglutinability with Evonymus lectin. These results suggest that the lectin receptor is a glycolipid.Since α‐linkedL‐fucose has been suggested as a part of the macrophage receptor for migration inhibitory factor in the guinea pig (Remold,J. Exp. Med.1973.138: 1065), the effect ofEvonymus europaealectin on the migration of PEC was studied. It was found that lectin inhibits the migration of PEC in the

ISSN:0014-2980    

DOI:10.1002/eji.1830130606

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractControl of functions mediated by the third component of complement (C3) depends on the rate of generation and degradation of biologically active C3 fragments. To evaluate the mechanisms of degradation of active C3 fragments, the role of the control protein C3b/C4b inactivator (factor I) was investigated under conditions approximating those foundin vivo, i.e.in the presence of plasma. The breakdown of human erythrocyte‐bound C3bi molecules in serum or plasma was mediated only by factor I, since factor I‐deficient or ‐depleted plasma was inactive until reconstituted with highly purified factor I. The rate of cleavage of C3bi bound to human erythrocytes by purified factor I was not affected by the presence or absence of β1H (factor H). The released breakdown product of C3bi has been shown to be C3c antigenically and on polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Two different monospecific antibodies to the human C3b receptor totally abrogated factor I‐mediated cleavage of cell‐bound C3bi, suggesting that the C3b receptor (but not factor H) is required as an obligate cofactor. The rate of this C3b receptor‐dependent, factor I‐mediated cleavage of bound C3bi is strongly regulated by the surface to which C3bi is bound. Whereas C3bi bound to particulate nonactivators of the alternative complement pathway such as human erythrocytes is rapidly degraded by this mechanism, the rate of cleavage of C3bi bound to activators is significantly slower. These data suggest a physiologic role of C3b receptors in the degradation of biologically active C3 fragments deposited on host tissues. They also suggest that C3bi molecules on restricted surfaces are relatively stable and can thereby interact with complement C3 re

ISSN:0014-2980    

DOI:10.1002/eji.1830130607

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractHuman peripheral blood mononuclear leukocytes cocultured with WISH human amnion cells or K562 tumor cells rapidly produce interferon‐α (IFN). In the present report we characterize the IFN‐producing cells (IPC) in this system by cell separation procedures, including panning with different monoclonal antibodies. Two types of cells which were responsible for the IFN production could be identified. The first IPC was classified as monocyte/macrophage because it was present in plastic‐adherent cells and apparently carried the OKM1 antigenic marker. T and B lymphocytes were not involved in the IFN production. The second type of IPC was nylon wool‐nonadherent, sheep erythrocyte rosette‐negative, at least partly Fc receptor‐negative and resided in light Percoll density gradient fractions. The natural killer activity and IFN‐producing capacity was studied in such cells fractionated by the panning technique, utilizing HNK‐1, OKT10 and OKM1 antibodies. When WISH and K562 were used as IFN inducers, HNK‐1+and OKT10+cells with lytic activity against K562 produced little or no IFN. The IPC were instead confined to HNK‐1−and OKT10−cells. With cells fractionated with respect to the OKM1 antigen, natural killer activity against K562 and WISH cells and IFN production stimulated by K562 cells resided in the OKM1+cells. In marked contrast, cells producing IFN in response to WISH cells were OKM1−.The results therefore demonstrate a dissociation between natural killer cells against tumor cells and IPC stimulated by the same targets, suggesting that for at least certain targets/inducers they may r

ISSN:0014-2980    

DOI:10.1002/eji.1830130608

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractThe effects of anti‐Lyt‐2 antibodies at different levels of lectin‐induced cytotoxic T lymphocyte (CTL) responses have been analyzed. Induction of interleukin 2 (T cell growth factor) reactivity (“step 1”) by three different lectins was profoundly inhibited by anti‐Lyt‐2 antibodies. Also lectin‐dependent cytotoxicity of polyclonally induced CTL was significantly inhibited by anti‐Lyt‐2 antibodies, whereas the interjacent IL2‐dependent proliferation of “step 1”‐induced CTL precursors was unaffected by these antibodies. The anti‐Lyt‐2‐mediated inhibition was selective and specific to the target cell determinants and limited to the events in CTL responses which require interactions with the lectins. These results parallel those obtained in antigen‐induced responses and indicate that antigens and lectins induce CTL responses by interacting with the same type of membrane receptor complex containing Lyt‐2 molecules and antigen‐specific receptors. It follows that T cell mitogenic lectins do not appear to deliver trigger

ISSN:0014-2980    

DOI:10.1002/eji.1830130609

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractB14−2−14 is a monoclonal cytotoxic IgM antibody which reacts with thymocytes of all mouse strains tested. The fraction of positive cells (by visual immunofluorescence) varies between strains from about 25–45% in A. CA to 65–85% in C57BL/6, and high levels are dominant in F1hybrids. In the periphery, the antigen is found on a few percent of lymph node and not on splenic T cells, and it is absent in nude mice. Among thymocytes, the distribution of the B14 determinant largely overlaps with that of the TL antigen and of molecules binding peanut agglutinin. The B14 antibody reacts only minimally with hydrocortisone‐resistant thymus cells. Biochemical analysis shows that B14 antibody, anti‐TL antibody and peanut agglutinin bind to separate molecules. The target of the B14 antibody may be either an immature, thymic form of Thy‐1, or another molecule associated with it. Two polypeptides, of 40 and 35 kDa are precipitated by both B14 and anti‐Thy‐1 antibodies from biosynthetically labeled thymus cell lysates, and two others, of 27 and 17 kDa, from surface‐iodinated thymus cell preparations. B14‐2‐14 offers an additional method for identification and selection of thymocytes at different stages of differentiation, and should also be useful for studi

ISSN:0014-2980    

DOI:10.1002/eji.1830130610

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractAnti‐idiotypes produced against monoclonal anti‐H‐2 antibodies have been used to examine idiotope sharing among a panel of anti‐major histocompatibility complex (MHC) antibodies detecting the same and different specificities. Both xenogeneic anti‐100‐30 and anti‐3‐83, which did not react with predominant idiotypes in conventional alloantisera, detected shared idiotopes on 3‐83 and 100‐30 as well as on 2 other monoclonal anti‐H‐2Kkantibodies. All 4 monoclonal antibodies recognized the same epitope cluster on the Kkmolecule and detected the same serological specificity, H‐2.5. In contrast, syngeneic and allogeneic anti‐idiotype produced against the same monoclonal antibodies did not detect these cross‐reactive determinants. In several instances, xenogeneic anti‐idiotype reacted with anti‐MHC antibodies which recognized distinct H‐2 determinants, suggesting that anti‐MHC antibodies detecting the same or different specificities may share idiotypic determinants. These reagents may be useful pro

ISSN:0014-2980    

DOI:10.1002/eji.1830130611

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY