摘要:

AbstractMice of different genotypes were immunized withSalmonella anatum.The cross‐reactivity patterns of their IgM anti‐S. anatumlipopolysaccharide (LPSAN) antibodies were characterized by their relative avidity toward heterologous LPS.When the LPS fromS. cholera suis(LPSCHS) was used as the heterologous LPS, clear differences between mouse strains were found. DBA/2 and DBA/1 showed cross‐reacting IgM, whereas C57BL/10, C57BL/6, BALB/c‐Igband B10.D2 had mainly noncross‐reacting IgM. In C3H and C57BL/6‐Iga, individual mice express either the cross‐reacting or the noncross‐reacting antibodies.The IgM antibodies from individual mice were further characterized for their cross‐reactivity toward the LPS fromS. strasbourg(LPSSTR) andS. illinois(LPSILL). Only individual patterns with no correlation to the cross‐reactivity pattern with LPSCHSwere found. This shows that more than one antibody type is characterized by cross‐reactivity.(B 10.D2 × DBA/1)F1mice showed a biphasic distribution of cross‐reactivity. Of the F1x DBA backcross mice 21 % had IgM antibodies which showed no cross‐reaction with LPSCHS.This still is in agreement with one locus controlling this phenotype.This locus segregates independently from Ig allotype since no correlation was found between allotype and cross‐reactivity patte

ISSN:0014-2980    

DOI:10.1002/eji.1830060602

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractInjection of mice already making antibodies to 2,4‐dinitrophenylated (DNP) Ficoll with tolerizing doses of DNP‐pneumococcal polysaccharide (DNP‐lys‐S3) markedly inhibits the secretion of anti‐DNP antibodies by IgM antibody‐forming cells. The present study shows that the degree of inhibition depends not only on the dose of DNP‐lys‐S3 but also on the duration of exposure to antigen. DNP‐ lys‐S3 was detectable on the surface of antibody‐forming cells at a time when their rate of secretion was unimpaired, thus suggesting that the inhibition involves intracellular events subsequent to the binding of antigen to the cell membrane. The inhibition was reversible if antibody‐forming cells were exposed to antigen for 24 h, and then cultured for 18 h in its absence, but became irreversible if the treatment period was extended to 48 h. The relevance of this model of inhibition of lymphocyte function by antigen to possible mechanisms of B cell

ISSN:0014-2980    

DOI:10.1002/eji.1830060603

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractFactor B of the alternative pathway of complement activation was shown to be synthesized and secreted by unstimulated mouse peritoneal macrophages. The activity of B in the culture supernatants from macrophage monolayers was detected by consumption of C3 in reaction mixtures containing supernatant and guinea pig factors C3,Dand insoluble C3b. Using a monospecific antiserum, factor B in concentrated culture supernatants was shown by immunodiffusion and immunoelectrophoresis to be identical to factor B in mouse plasma and to form a characteristic complex with cobra venom factor in the presence ofD. A steady rate of factor B secretion was observed for 4 days providing the medium was changed every 24 h. Cycloheximide (0.5 μg/ml), an inhibitor of protein synthesis, caused inhibition (90%) of factor B production. Incubation of culture medium containing14C‐labeled amino acids with the macrophage monolayer resulted in incorporation of radioactivity into factor B as detected by autoradiography of precipitation lines formed with anti‐B antiserum. This indicated that synthesis of factor B had occurred. In the same culture supernatants the presence of newly synthesized C3 was also demonstr

ISSN:0014-2980    

DOI:10.1002/eji.1830060604

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractSpleen cells, from BALB/c mice primed with keyhole limpet hemocyanin (KLH), were stimulated with heat‐killed vaccine of roughPneumococcus pneumoniaeR36A (Pn) and/or phosphorylcholine (PC)‐coupled KLH to induce an anti‐PC responsein vitro.The response to PC‐KLH was found to be T‐dependent while it is T‐independent to Pn. The antibodies induced with either antigen had similar avidity and expressed the TEPC 15 idiotype exclusively; thus T cell involvement in the response to PC‐KLH failed to alter these parameters of the anti‐PC response.At the precursor cell level, Pn induced small clones with an average size of 10 plaque‐forming cells (PFC), whereas PC‐KLH gave rise to larger clones of 40–50 PFC. This difference in the proliferative potential of PC precursor B cells hinted at the possibility that Pn and PC‐KLH were stimulating different precursors. This was corroborated by the observation that a) when Pn and PC‐KLH were added to the same cultures a synergistic effect was seen,i.e.the number of plaques was greater than the sum of the responses induced by each antigen, and b) in microcultures, under conditions limiting B cells only, Pn plus PC‐KLH induced a higher fraction of responding wells than either antigen on its own. We postulate that Pn and PC‐KLH stimulate subpopulations of PC precursor cells which are T‐independen

ISSN:0014-2980    

DOI:10.1002/eji.1830060605

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractA previously designed isotopicin vivomethod for measuring delayed hypersensitivity was used with nonantigenic (or weakly antigenic) phlogogenic substances. A strong reaction was observed in some circumstances, witnessing the fact that the method has a specific and a nonspecific component. The reaction is drastically augmented by a mild whole‐body irradiation of the reacting animals. In the case of the studied substances (carbon, oil and bentonite) the reaction is bound by polymorphonuclear neutrophils (PMN), but it was found to be independent of the number of circulating PMN in the bloo

ISSN:0014-2980    

DOI:10.1002/eji.1830060606

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractPeptide fragments, obtained from equine growth hormone by cyanogen bromide cleavage and further chemical treatment, were isolated and identified. Their immunological reactivities were tested by hemagglutination and complement fixation methods using rabbit antisera against native hormone.Antigenic determinants were detected in the fragments comprising amino acid sequences 5–72 and 73–123, this last one being predominant. Fragment 124–178 had very low reactivity. Nitration of peptide 73–123 did not modify its immunological properties, but oxidation diminished them.Comparison of the antigenicity of equine growth hormone fragment 73–123 with that of the homologous ovine growth hormone fragment 86–123 lent support to the hypothesis that at least one antigenic determinant area in the horse hormone fragment is dependent on sequ

ISSN:0014-2980    

DOI:10.1002/eji.1830060607

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractImmune guinea pig lymph node cells were fractionated on Ig anti‐Ig or HSA anti‐HSA affinity columns or on plastic surface in medium containing carbonyl iron. These techniques selectively removed B lymphocytes, K lymphocytes or adherent cells. The residual cells (Fc receptor‐negative T lymphocytes) responded to soluble antigenin vitroin the same way or even better compared with nonfractionated cells. In addition, there was no indication that antigen‐antibody complexes were superior to antigen in triggering lymph node cells or purified lymph node T lymphocytes into DNA synthesis. The results obtained suggested that memory T lymphocytes can be stimulated by antigen auton

ISSN:0014-2980    

DOI:10.1002/eji.1830060608

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractTwo sublines of CBA/H mice congenic for the Igl allotype locus were used to study donor‐allotype IgG2aconcentrations in the serum of mice injected intravenously with thymus cells. High concentrations (up to several mg/ml) were found in x‐irradiated recipients(exposed to 650 rad, or to 900 rad with a restorative injection of fetal liver cells). The highest concentrations were seen 1–2 months after injection, but detectable quantities were still present in most individuals after 377 days. No donor‐allotype Ig was detected in non‐irradiated recipients. Cell for cell, lymph node cells were about as efficient as thymus cells at transferring IgG production. Although pluripotent hema‐ topoietic stem cells were found in the thymus, their concentration (about 10−8) was too low to account for the results. It is suggested that the thymus contains B lymphocytes, or their precursors, with considerably greater powers of self‐maintenance and expansion than are possessed, on average, by the B lymphocytes

ISSN:0014-2980    

DOI:10.1002/eji.1830060609

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractDinitrophenylated polysucrose (DNP‐Ficoll) elicits T cell‐independent IgM anti‐DNP antibody formation in mice. This antigen also elicits a heterogeneous IgG1 and IgG2 anti‐DNP response, which is operationally as T‐independent as the IgM response. However, a concomitant graft‐versus‐host reaction markedly enhances the IgG response (allogeneic effect). These results confirm those of others, indicating that a certain proportion of the precursors of IgG‐producing cells can be triggered by some T‐independent antigens. However, our results suggest that even with such antigens optimal triggering of IgG precursors req

ISSN:0014-2980    

DOI:10.1002/eji.1830060610

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractIncubation of trinitrophenylated hemocyanin (TNP‐KLH)‐primed spleen cells with microgram amounts of 2,4‐dinitrophenyl (DNP) or 2,4,6‐trinitrophenyl (TNP) conjugates of pneumococcal polysaccharide type 3 (SIII) for as little as 5 min at 4 °C results in a specific “block” of the 19 S and 7 S adoptive memory response to TNP‐KLH. This hapten‐SIII‐induced block of anti‐hapten memory B cell responsiveness seems to be an example of specific receptor blockade. The block is specific and can be prevented by simultaneous incubation of the primed cells with hapten‐protein conjugates which presumably compete with the hapten‐polysaccharide for attachment to the B cell surface via anti‐hapten Ig receptors. Removal via capping of these Ig receptors by exposure of TNP‐KLH‐primed memory cells to rabbit anti‐mouse Fab serum for 45 min at 37 °C renders these cells refractory to the blocking effect of hapten‐SIII. Once the hapten‐SIII has attached to the memory cells, these blocked cells can be “rescued” (i.e.returned to a state of responsiveness) by incubating these cells with either mouse anti‐SIII at 37 °C or rabbit anti‐DNP serum at 4 °C. Since a papain digest of the IgG fraction of rabbit anti‐DNP did not rescue the cells while the intact IgG did, a capping off of the TNP‐SIII was proposed as the mechanism for this return to responsiveness of the hitherto blocked cells. A rescue was not seen by treatment of recipient mice with such B cell mitogens as dextran sulfate, end

ISSN:0014-2980    

DOI:10.1002/eji.1830060611

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY