摘要:

AbstractSeveral Ia+tumor cell lines and peritoneal exudate macrophages were tested as accessory cells (AC) for the activation of antigen‐specific T cells and for T‐B cooperation. The macrophages and all the Ia+tumor lines tested induced the release of lymphokines from T cells in a major histocompatibility complex (MHC)‐restricted fashion and reconstituted the antibody responses of AC‐depleted spleen cells or of purified T and B cells. However, only the normal macrophages but none of the tumor lines induced carrier‐specific T helper (Th) cells which help B cells for specific anti‐hapten antibody responses by linked recognition. For T‐B cooperation accessory cells were also required, but in contrast to ThCell activation any type of Ia+AC (e.g. macrophage or tumor line) was effective. Strong MHC‐restriction between the lymphocytes and the AC was seen if antigen‐pulsed AC were added into the AC‐depleted T‐B cooperation cultures. If the AC and antigen were concomitantly added to the AC‐depleted T‐B cultures, MHC‐restriction was less obvious. Concanavalin A supernatant reconstituted the response of AC‐depleted T‐B cultures provided antigen‐specific Thcells and the hapten‐carrier conjugate were present. If, however, tumor line‐activated T cells were added instead of macrophage‐induced Thcells, no cooperation with B cells took place even in the presence of Con A supernatant. The results obtained demonstrate a differential AC requirement for the induction of Thcells depending on t

ISSN:0014-2980    

DOI:10.1002/eji.1830150102

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractThe three mitogenic anti‐T3 antibodies, UCHT1, anti‐Leu‐4 and WT‐32, all produce a rapid increase in T cell intracellular Ca2+([Ca2+]j) in all individuals, as measured by quin2 tetra‐acetoxymethyl ester fluorescence. This indicates that the lack of responsiveness of approximately 30% of individuals to UCHT1 in proliferation assays is not due to failure of the antibody to elicit Ca2+mobilization and that a rise in [Ca2+]j is per se not adequate to induce cell division. Another mitogenic antibody, WT‐31, which is directed against the constant portion of the T cell receptor, did not, however, produce a rapid calcium rise in peripheral blood T cells. The clone HA1.7 gave a similar Ca2+response to UCHT1. WT‐31 did not induce a rise in [Ca2+]j, nor did the specific antigen to which the clone responded. Accessory cells may be required to induce Ca2+mobilization with these ligands. There was no response to IL2, or an antibody (anti‐ Tac) to the IL2 receptor. In contrast to peripheral blood T cells treatment of HA1.7 with WT‐31 led to an enhancement of the calcium response to subsequent UCHT1 addition. Furthermore, cross‐linking of WT‐31 on the surface of HA1.7 cells did produce a small rise in [Ca2+]j. The IL2‐independent malignant T cell line, HUT78, exhibited a calcium response to both UCHT1 and WT‐32. Both of these responses occurred without cross‐linking.The T cell receptor is closely associated with cell‐surface proteins, including the T3 antigen and these studies confirm the importance of the T3 antigen in T cell activa‐ tion. They also suggest that the relationship between the T cell receptor and the T3 antigen may vary in T cells in

ISSN:0014-2980    

DOI:10.1002/eji.1830150103

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractClass II major histocompatibility complex determinants restricting recognition of tuberculin antigens (purified protein derivative; PPD) were studied by using mono‐ clonal antibodies (mAb) to block lymphoproliferative responses. Anti‐class I1 mAb were shown to exert inhibitory effects at the level of the antigen‐presenting cells, without inducing suppressive lymphocytes or macrophages. Using panels of HLA‐ typed antigen‐presenting cells and nonalloreactive proliferative T cell lines, derived by limiting dilution, restriction elements for PPD responses appeared to correlate with the donor's HLA‐DRw6 specificity (one clone), MB1 (one clone), MB3 (one clone), or no established class II (or class I) specificity (three clones). mAb TÜ22, reacting with nonpolymorphic DC‐like determinants, strongly inhibited stimulation of all clones except that restricted by DR antigens, suggesting the DC‐like character not only of the MB1‐ and MB3‐associated, but also of the unassigned, restriction elements of these cloned lines. In contrast, stimulation of the DR‐restricted line was strongly inhibited by DWSB‐specific mAb which only weakly inhibited the stimulation of clones restricted by DC‐like determinants. These results suggest that clonally distributed PPD‐reactive proliferative lymphocytes from a single donor may be restricted by at least three different class Il determinants (HLA‐DR, MB, or a secon

ISSN:0014-2980    

DOI:10.1002/eji.1830150104

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractThis report describes the role of T cell‐derived lymphokines in induction of macrophage (Ma) tumor cytotoxicity. M tumor cytotoxicity was tested with the murine Ma‐like tumor PU5‐1.8. This MΦ‐like tumor reacts to stimulation with T cell‐derived lymphokines and shows tumor cytotoxicity comparable to resident peritoneal MΦ. The experiments demonstrate that immune interferon (IFN‐γ) secreted by T cell clones in limiting dilution microcultures was insufficient to induce MΦ tumor cytotox icity. Induction of MΦ tumor cytotoxicity by T cell‐derived supernatants with quantities of IFN‐γ undetectable in the IFN assay, however, was completely inhibited by an antiserum raised against recombinant IFN‐γ. Taken together, these results could be thus explained: (a) a T cell‐derived lymphokine distinct from but serologically cross‐reactive with IFN‐γ induces MΦ tumor cytotoxicity, and (b) IFN‐γ activity in supernatants positive for induction of MΦ tumor cytotoxicity escapes detection in the IFN assay but can still be inhibited by the anti‐IFN‐γ antiserum in the MΦ tumor cytotoxicity assay. The latter explanation requires positive evidence for another T cell‐derived lymphokine inducing MΦ tumor cytotoxicity together with IFN‐γ. This lymphokine was found in the supernatant of T cells in limiting dilution cultures and a long‐term T cell clone and was called Mγ cytotoxicity‐inducing factor 2 (MCIF2). MCIF2 synergizes with IFNγ induction of MΦ tum

ISSN:0014-2980    

DOI:10.1002/eji.1830150105

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractInjection of (CBA × A)F1cells into neonatal CBA mice rendered them tolerant to skin grafts of (CBA × A)Fi origin. Limiting dilution analysis revealed a very low frequency of tolerogen‐inducible cytotoxic T lymphocyte precursors (CTL‐P) in spleens of tolerant mice. Twoin vitroprocedures allowed, however, the induction of tolerogen‐specific CTL‐P of high frequencies in tolerant mice: (a) the “by‐pass” activation of spleen cells from tolerant mice by concanavalin A under short‐term bulk culture conditions followed by culture of limiting numbers of activated responder cells, and (b) absorption of spleen cells from tolerant mice on monolayers of tolero‐gen‐activated T cells from normal syngeneic mice. Furthermore, spleen ceils from tolerant mice, recently challenged with a tolerogen ‐ bearing skin graft, specifically suppressed the activation of tolerogen ‐ reactive splenic CTL‐P from normal CBA mice under limiting dilution conditions. These data confirm the presence of tolerogen‐specific CTL‐P of high frequency in tolerant mice and suggest their functional inactivation

ISSN:0014-2980    

DOI:10.1002/eji.1830150106

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractTwo rat monoclonal antibodies (mAb) have been produced which recognize a clonespecific determinant on the alloreactive cytotoxic T lymphocyte (CTL) clone 3F9. CTL clone 3 F9 of BALB/c origin is specific for H‐2Dband can be grown by weekly restimulation with irradiated stimulator spleen cells expressing H‐2Dbin the presence of interleukin 2. Two mAb against T cell clone 3F9, 44‐22‐l(IgG2a) and 46‐6 B5(IgM), have been proven to be clone specific: they inhibit cytotoxic activity of 3F9 only and bind specifically to 3 F9 when compared in a panel of different CTL clones, or cells from different mixed lymphocyte cultures (MLC), BALB/c thymus and spleen cells. The mAb 44‐22‐1 has been used to sort cells from a primary MLC BALB/c anti‐ H‐2Dbby fluorescence‐activated cell sorter (FACS) to select CTL expressing 3 F9 clonotype‐specific determinants. The lymphocytes reactive with 44‐22‐1 represent a minor subpopulation of the CTL of the primary MLC. The specific alloreactive cytotoxicity of unsorted lymphocytes of the bulk primary MLC could not be inhibited by the mAb 44‐22‐1 and 46‐6 B5 whereas the sorted 3 F9 clonotype‐positive cultures could be inhibited very effectively. All the CTL clones derived from the FACS‐sorted clonotype‐positive culture show all the same properties and are identical with clone 3F9 with respect to antigen‐specific cytotoxicity, inhibition of cyto

ISSN:0014-2980    

DOI:10.1002/eji.1830150107

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractThe thymic nurse cell (TNC) consists of an epithelial cell enclosing lymphoid elements and is found in enzymic digests of the thymus. Although these structures have been implicated in the normal intrathymic development of T lymphocytes, little is known about thein situstructure of this unusual cell complex. In this study, various dyes were introduced into the intact thymus and their differential permeability was used to demonstrate that the TNC exists as a sealed structurein situ.The lymphocytes within the TNC were shown to be isolated from the general thymic environment. Prelimi‐ nary studies on these lymphocytes and the physiology of their active release from individual, micromanipulated TNC in microcultures are reporte

ISSN:0014-2980    

DOI:10.1002/eji.1830150108

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractThe antagonistic effects of macrophage (MΦ)‐derived interleukin 1 (IL1) and prostaglandin Ez(PGE2) on thymocyte proliferation were uncoupled and studied. Elimination of PGE2from the culture medium of prostaglandin Ez‐stimulated MΦ was achieved by dialysis of the media or by indomethacin treatment of the Ma. IL1 secretion appears to be PGE2independent. Experiments using exogenous PGEzrevealed a quantitative relationship between the two monokines. PGE2(1.25 ng/ml) reduced the proliferative effect of IL 1 produced by 1.5 × 105peritoneal MQ, to 50%. This PGE2dose increased significantly the levels of intracellular cAMP. Separation of peritoneal exudate MΦ on a bovine serum albumin discontinuous gradient demonstrated that the main part of PGE2synthesis was in a fraction of lower density, large MΦ, whereas IL1 activity was detected in all tested f

ISSN:0014-2980    

DOI:10.1002/eji.1830150109

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractHuman peripheral blood monocytes were separated into four different subpopula‐tions by means of a discontinuous bovine serum albumin gradient. Of the least dense population, 7% were present in fraction A, 11% in fraction B, 28% in fraction C and of the most dense, 34% were in fraction D. The rest (17%) of the recovered cells sedimented as a pellet, of which 95% were dead. The monocytes of fraction D (ϱ = ⩾ 1.075 kg/l) were major interleukin 1 (IL1) producers and their presence enhanced immunoglobulin synthesisin vitro. Fraction C (ϱ = ⩾ 1.070 kg/l) were the major prostaglandin E2(PGE2) producers and demonstrated suppressor activity onin vitroIgG and IgM synthesis. Fractions A and B had minimal production of either IL1 or PGE2and lesser effects on the IgG and IgM synthesis. These data demonstrate functional heterogeneity of peripheral blood monocytes with respect to production of both IL1 and PGE2as well as accessory cells for immunoglobulin sy

ISSN:0014-2980    

DOI:10.1002/eji.1830150110

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY

摘要:

AbstractIn man, B cell maturation factors obtained from T cells or T cell lines have been shown to induce antibody formation in mitogen or anti‐immunoglobulin activated B cells, and in some continuous B cell lines, but the relationships between these factors and B cell differentiation factors in antigen‐specific antibody responses is unclear. We have now shown that supernatants from phytohemagglutinin‐activated tonsil cells, or from the Gibbon Ape T cell line ML A‐144, can substitute for T cells in the specific antibody response by human blood B cells to influenza virus. Thus, T cell‐depleted non‐rosette‐forming (E−) cells prepared from peripheral blood mononuclear cells made antibody when cultured with antigen and factor together, whereas control cultures of E−cells with either antigen or factor alone did not. Moreover, E−cells cultured with factor and influenza virus strain A/X31 made antibody to A/X31, but not the non‐cross‐reacting strain, B/HK (andvice versa)showing that the response was antigen specific. The activity in these supernatants, therefore, fulfilled the functional definition of T cell‐replacing factor (TRF). The possibility that interleukin 2 (IL2) present in the TRF‐containing supernatants was expanding residual T cells in the E−preparations to provide normal T cell help was excluded in three different ways. First, E−cells depleted of T (Leu4+) cells to undetectable levels made normal amounts of antibody when cultured with antigen and TRF. Secondly, a limiting dilution technique was employed to show that help in cultures of E−cells and TRF was not mediated by antigen‐specific T helper cells. Thirdly, TRF‐containing supernatants depleted of IL2 retained activity, whereas purified IL2 was inactive. Preliminary purification of TRF by gel filtration on Ultrogel AcA54 columns showed that all the activity eluted in a single peak between 35000 and 43000 molecular weight. This distinguishes human TRF from IL2 and from other B cell maturation factors with a molecular weight range of 15000–20000 which act on continuous Bcell lines.In addition to TRF, supernatants from phytohemagglutinin‐activated tonsils also contained a factor which could induce polyspecific IgM production, but only in cultures containing significant numbers of T cells. This additional activity may have been due to IL2, and provides an explanation for the apparent T cell‐dependent effects sometimes observed in experiments designed to test B cell differentiation

ISSN:0014-2980    

DOI:10.1002/eji.1830150111

出版商:WILEY‐VCH Verlag GmbH    

年代:1985

数据来源: WILEY