摘要:

AbstractSpecific secondary cytotoxic reactivity (as measured by51Cr‐release assay) against SV 40‐induced tumor‐associated antigens was generatedin vitroin spleen cells of tumor‐free (BALB/c × C57 BL/6)F1(CBF1) mice immunized against a syngeneic SV 40‐induced tumor of BALB/c origin (mKSA), followingin vitrosensitization for 5 days with the relevant antigens in mixed lymphocyte‐tumor cell cultures. In contrast, spleen cells of CBF1mice bearing the SV 40‐induced tumor demonstrated suppressed specific secondary cytotoxic reactivity following incubation with the corresponding antigens. Spleens from tumor‐bearing mice contained 4 times the number of mononuclear cells and 3 times the percentage of macrophages, as compared to spleens of normal mice. The percentage of B cells was also elevated in spleens of tumor‐bearing mice. There was a slight reduction in the percentage of T cells. The cytotoxic reactivity of spleen cells of tumor‐bearing mice was restored following removal of macrophages by either rayon adherence columns or iron and magnet, or incubation on plastic petri dishes. No such effect was seen with spleen cells of tumor‐free or normal mice. Spleen cells of tumor‐bearing mice inhibited thein vitrogeneration of secondary cytotoxic reactivity of spleen cells of tumor‐free mice, sensitizedin vitrowith SV 40‐induced tumor cells by mixing experiments. The suppressor cells were found to be macrophages by the 3 techniques for removal of macrophages described above. The addition of indomethacin (1–10 μg/ml), a noncompetitive irreversible prostaglandin synthesis inhibitor, to cultures of responding spleen cells from tumor‐bearing mice and stimulating SV 40‐induced tumor cells resulted in marked augmentation of spleen cells responsiveness. With higher indomethacin concentrations (100 μg/ml), no enhancement was seen. The augmenting effect was noted only when indomethacin was present during the initial 24 h of the 5‐day culture. Indomethacin at 1–10 μg/ml had no effect on cytotoxic reactivity of spleen cells of tumor‐free mice, whereas at higher concentrations (100 μg/ml) it had a strong suppressive effect. Preincubation of spleen cells of tumor‐bearing mice with indomethacin for 3 days abrogated their ability to suppress the generation of secondary cytotoxic reactivity of spleen cells of tumor‐free mice. It is hypothesized that indomethacin‐sensitive suppressor macrophages regula

ISSN:0014-2980    

DOI:10.1002/eji.1830100702

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

AbstractThe papain‐solubilized fragment of the H‐2Ddantigen, representing the NH2‐terminal 80% of the native glycoprotein, can be fragmented into five polypeptides using CNBr cleavage. These fragments have been isolated, characterized and subjected to amino acid sequence analysis using radiochemical microtechniques. It was possible to align these CNBr fragments by comparison of their NH2‐terminal amino acid sequence with the known amino acid sequence of the H‐2 Kbmolecule. Thus, the NH2‐terminal fragment, D, contains 23 residues and is followed by a glycopeptide, fragment C, of 75 residues. Following fragment C are three fragments held together by disulfide bonds: fragment b 4, which has 40 amino acid residues, a second glycopeptide, fragment b 2, of 90 residues, and fragment b 3, a peptide of approximately 55 residues which terminates at the site of papain cleavage. The complete amino acid sequence of the NH2‐terminal CNBr fragment, D, has been determined, and this is presented here along with sequence data for the NH2‐terminal 30 residues of each of the other four CNBr fragments of the papain fragment of H‐2Dd. A total of 146 positions have been examined in the approximately 280‐residue H‐2D papaindmolecule, and a total of 127 residues have been positively determined. Most of the unassigned positions may be tentatively assigned as Asp or Asn, the only amino acids so far not incorporated in radiolabeled form by our metabolic labeling procedures into the H‐2 Ddmolecule. Comparison of the sequence data obtained for the H‐2 Ddmolecule to data available for other histocompatibility antigens revealed homologies of approximately 90% with H‐2 Kband H‐2 Ld, and approximat

ISSN:0014-2980    

DOI:10.1002/eji.1830100703

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

AbstractMonoclonal antibody (McAb) H9/25 has previously been shown to react with an alloantigen expressed on subpopulations of mouse lymphocytes. We here investigated the expression of the antigen (H9/25 Ag) on functional subsets of T and B cells. Lymphocytes were depleted of H9/25 Ag‐bearing cells by complement‐dependent cytolysis or by the affinity to immobilized McAb H 9/25, and the residual immunological functions were tested. In these tests, killer T cells generated in mixed lymphocyte cultures and their precursors were found to express H9/25 Ag. In contrast, the activity and frequency of helper T cells specific to keyhole limpet hemocyanin carrier were not decreased by the depletion of H9/25 Ag‐bearing cells. On the other hand, IgG and IgM anti‐TNP plaque‐forming cells were found to express H9/25 Ag, while it was not detected on unprimed B cells, as tested by using TNP‐Ficoll and TNP‐lipopolysac‐charide. Only a small proportion of TNP memory B cells seemed to express the antigen. These results revealed significant differences between H 9/25 Ag and other known alloantigens in the distribution among functional subsets

ISSN:0014-2980    

DOI:10.1002/eji.1830100704

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

AbstractThe fine specificity of murine B 10.A/SgSn (B 10.A) T cells reactive with hen egg‐white lysozyme (HEL) has been studied through the use of reduced, carboxymethylated HEL, a set of peptides encompassing the entire molecule, and a set of variant lysozymes from other species. Cells were taken from the lymph nodes draining the site of immunization at the base of the tail, and were restimulatedin vitrowith immunogen or analogue to measure T cell reactivity.Unlike B cell reactivity, which we have shown to be mainly associated with an epitope preserved in the N‐C peptide (residues 1–17, Cys 6‐Cys 127, 120–129) most T cell reactivity appears to be directed towards a limited number of determinants on cyanogen bromide cleavage fragment II of HEL (LII) (13–105). This was confirmed by a cell‐dilution assay in which antigen‐reactive units are measured; reactivity was highest to LII, intermediate to N‐C, and low but significant to cyanogen bromide cleavage fragment III (LIII) (106–129). Furthermore, priming with LIIis as effective as immunization with HEL and results in the same extensive cross‐reactivities to variant lysozymes.Although LIIreactivity predominates in the response to HEL, injection of LIIIand N‐C reveals sizeable reactivity to the homologous peptides and to HEL. By crossstimulation studies, specific epitopes could be defined in certain regions of HEL. B 10. A is clearly responsive to the overlap between N‐C and LII(residues 13–17), and to an epitope in the region 106–121, but is poorly responsive to the C‐terminal portion (120–129). The response to 106–121 is characterized by an exquisite specificity in which as little as a single amino acid subst

ISSN:0014-2980    

DOI:10.1002/eji.1830100705

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

AbstractTwo distinct modes of unresponsiveness to hen egg‐white lysozyme (HEL) have been demonstrated in the “nonresponder” C57 BL/10 Sn (B10) mouse strain at the level of T cell proliferation. The first is an apparent inability to respond to a peptide of HEL comprising 70% of the molecule, LII(amino acids 13–105), when HEL is used as immunogen. On its own, LIIis capable of eliciting a strong response from B10 draining lymph node cells, but this capacity is concealed when the whole molecule is used for immunization (by suppressor cell activity raised against another part of HEL, as described by Adorini et al.,J. Exp. Med.1979.150: 293). In the B 10.A mouse, LIIand HEL are equally immunogenic.The second is an actual failure, presumably unrelated to suppression, to contrive a response to particular determinants on HEL, demonstrated for certain epitopes on LIIand LIII(amino acids 106–129). Such a failure to respond was maintained despite an increase in the immunizing dose of peptide to a molarity at which HEL itself could overcome Ir gene control. B10 cells responding to a high dose of HEL, or to the immunogenic lysozyme from ring‐necked pheasant, were also unable to respond to these epitopes.These deficits in responsiveness appear to be characteristic manifestations of the relevant haplotype of the major histoconapatibility complex. They may not only reflect the balance between competing T cell subpopulations, but also the constraints of associative recognition that may underlie the presentation of particular antigenic sp

ISSN:0014-2980    

DOI:10.1002/eji.1830100706

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

AbstractFully allogeneic, chimeric mice were established by adult thymectomy of (A × B) F1animals, grafting parental A‐type thymus under the kidney capsula, followed by lethal (900 rd) irradiation and reconstitution with B parental‐type bone marrow cells treated with xenogeneic anti‐T cell antiserum plus complement. Followingin vivosensitization with inactivated Sendai virus (SV) suspensions, no virus‐specific T cells could be detected within the spleen cells of the mice. Upon stimulation with third‐party allogeneic cells in a primary mixed lymphocyte culture, spleen cells of all animals generated alloreactive cytotoxic T lymphocytes (CTL). More interestingly, upon secondaryin vitrostimulation with inactivated SV‐conjugated B‐type stimulator cells, B‐type‐restricted, virus‐specific CTL were inducible in each case. Upon restimulation with SV‐conjugated A‐type stimulator cells, A being the H‐2 type of the grafted thymus, T cells of some but not all mice generated A‐type‐restricted, virus‐specific CTL. The data suggest that in allogeneic, chimeric mice virus‐specific CTL can be induced. Moreover, virus‐specific CTL, restricted to the H‐2 type of the lymphoid stem cell inoculum, are more readily inducible than those restricted to

ISSN:0014-2980    

DOI:10.1002/eji.1830100707

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

AbstractIn contrast to normal IgG, some of the IgG molecules, which appear in compensation as a result of allotype suppression of IgG molecules of the major VHsubgroup (a locus), were found to have an easily identifiable idiotypic specificity. For each of three donors' IgG, a different idiotypic specificity was present, and each idiotypic specificity was found on the Fab, as expected, but not on the Fc fragment. Further analysis of the IgG of one donor revealed that the idiotypic specificity was present on 15% of the Fab γ fragments. The idiotypic specificity was expressed on IgG which also bore an allotypic specificity of the y locus VHsubgroup of IgG which comprised most (72%) of the total compensatory IgG. This suggests that suppression of clones synthesizing the a locus major VHsubgroup results in compensation by minor VHsubgroup clones more limited in variability. These clones may then proliferate to synthesize larger amounts of IgG bearing the same idiotypic specificity which thereby becomes more easily detectable by immunization of rabbits

ISSN:0014-2980    

DOI:10.1002/eji.1830100708

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

AbstractRabbit anti‐SII pneumococcal polysaccharide IgG antibody was cross‐linked by dithiobis (succinimidyl propionate). The IgG dimers were visualized by electronmicroscopy and resembled two Y‐shaped structures connected in random orientations. The three arms of the Y's were of equal length. The six globular domains of the IgG protomers could be seen, but the Fab arms and Fc stems could not be distinguished from each other. Electron microscopy revealed that the dimers were bound to the globular heads of C1 q. From the dependence of the weight average molecular weight on dimer concentration, an equilibrium constant of about 106M−1was derived for the binding of dimers to C1 q. The number of IgG dimers which could be accommodated at a single C1q molecule was derived to be three. The data do not allow a clear distinction between noncooperative and cooperative binding.The binding equilibrium was independent of whether the IgG dimers were liganded with an SII nonasaccharide hapten or not. The results are at variance with an allosteric mechanism of the action of antigen in C1 activation. They lend support to the association hypothesis of complement activation. The data suggest that clusters of about six IgG molecules, connected by a multivalent antigen or arranged at the cell surface, are recognized by C1 q with a binding constant of about

ISSN:0014-2980    

DOI:10.1002/eji.1830100709

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

AbstractThe present experiments analyze the functional properties of helper T cells specific for “minor” histocompatibility antigens. T cells from C3H/HeJ mice, primedin vivoand highly enrichedin vitrofor reactivity to membrane antigens of C3 H/Tif B cells, specifically proliferate, and provide polyclonal help to splenic B cells from strains carrying a variety of different H‐2 haplotypes on C3H or BALE backgrounds, while failing to respond to cells carrying the same H‐2 haplotypes on C 57 BL or A backgrounds. Since it has been previously demonstrated (A. A. Augustin and A. Coutinho,J. Exp. Med.1980.151: 587) that B cell activation in this system strictly requires direct, specific recognition of B cell surface antigens by helper cells and does not result from the production of soluble “mitogenic” or “nonspecific helper factors”, it is concluded that this phenomenon represents specific, major histocompatibility complex (MHC)‐unrestricted T cell help. In addition, it has now been found that expression of helper activity requires viability of the helper cells and is partially radiation‐sensitive. Lack of MHC restriction is not a general property of specific helper cells which directly recognize B cell “minor” antigens, since BALB.C3 H anti‐C3 H/Tif T cells appear to be restricted by H‐2 in their polyclonal helper activity. The helper activity mediated by specific anti‐“minor”, H‐2‐restricted helper cells could not be inhibited by anti‐VHantibodies, and the inhibition obtained with anti‐Ia antibodies appeared to operate at the level of B cell induction, rather th

ISSN:0014-2980    

DOI:10.1002/eji.1830100710

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY

摘要:

AbstractLymphokines produced by antigenic or mitogenic stimulation of human, guinea pig and mouse lymphocytes were tested for their effects on monocytes or macrophages of the same and heterologous species, to determine whether there is any species restriction in their reactivity. Supernatants from lymphocyte cultures were tested for migration inhibitory activity in an indirect agarose microdroplet assay and for their ability to augment cytolytic activity of macrophages or monocytes in a [3H] thymidine‐release assay. Supernatants of human peripheral blood mononuclear cells, stimulated with phytohemagglutinin or purified protein derivative of tuberculin (PPD) were able to strongly inhibit the migration of human monocytes and guinea pig peritoneal exudate cells (PEC), but had no detectable effect on mouse PEC. The human Supernatants could also significantly augment the cytolytic activity of human monocytes, but had no effect on cytotoxicity by mouse peritoneal macrophages. Conversely, Supernatants of PPD‐stimulated spleen cells from mice immune to bacillus Calmette‐Guérin (BCG) strongly inhibited the migration of, and significantly augmented cytolysis by, mouse PEC, but had no detectable effects on human monocytes. Moreover, Supernatants of concanavalin A‐stimulated lymph node cells from guinea pigs inhibited the migration of guinea pig PEC and human monocytes, but had no effects on mouse PEC. The migration inhibitory effects of the human and mouse Supernatants did not appear to be mediated by interferon (IF), since partially purified type‐1 IF had no detectable effect. In addition, Supernatants of human lymphocytes stimulated byCorynebacterium parvumstrain 5888, that induced little or no IF, were able to inhibit the migration of, and augmented cytolysis by, human monocytes. TheseC. parvumsuper‐natants also showed migration inhibitory activity on mouse PEC but did not induce cytolytic activity in

ISSN:0014-2980    

DOI:10.1002/eji.1830100711

出版商:WILEY‐VCH Verlag GmbH    

年代:1980

数据来源: WILEY