摘要:

AbstractAddition of mercaptoethanol to the culture medium has permitted a mixed leukocyte interaction (MLI) to be achieved with mouse spleen cells in a chemically defined protein‐free medium. Results which confirm those obtained in culture medium supplemented with heterologous sera are: 1) the maximum incorporation of isotope occurred between 60 and 72 h of culture; 2) the index of stimulation was 3–15; 3) the number of responder and stimulator cells required for maximum incorporation was 3 x 106– 4 x 106and 4) immunization resulted in a higher level of incorporation that occurred earlier than the maximum response of normal cells. Other results obtained confirm previous reports which are in apparent conflict:i.e., 1) stimulation of parental strains (P1) by F1hybrids (P1x P2) may be either equal to or one‐half that induced by the other parental strains (P2); and 2) F1hybrids may or may not be stimulated by the parental strains. These latter two results were found to be dependent on the strains used. Other advantages of the system are discussed in terms of the elimination of artifacts that occur in medium containing serum and the usefulness in examination of molecular events occurring early in immune re

ISSN:0014-2980    

DOI:10.1002/eji.1830030702

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

摘要:

AbstractThis report describes the enhancement of the mouse mixed lymphocyte interaction which results from supplementing a protein‐free medium with either isologous or homologous sera. The degree of stimulation is affected by several variables which include serum preparation and concentration, the genetic relationship of the responder and stimulator cells to the source of sera, and the composition of the mediu

ISSN:0014-2980    

DOI:10.1002/eji.1830030703

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

摘要:

AbstractA dilution scheme for bone marrow‐derived (B) cells has been applied to estimate the frequency of precursor cells specific to sheep red cells (SRC) present in the spleens of nude mice.B cells were titrated over a range of 0.2 x 105– 1.8 x 105spleen cells of nude mice per microculture in the presence of a constant number of allogeneic spleen cells. Data from 6 limiting dilution experiments are presented. It is argued that only the B cells are being diluted out. The frequency of precursor cells specific for SRC was calculated by means of Poisson statistics. The estimates of these frequencies are in the range 0.9 x 10‐5– 2

ISSN:0014-2980    

DOI:10.1002/eji.1830030704

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

摘要:

AbstractComplementation experiments were carried out in which allogeneic spleen cells were added to the spleen cells from nude mice. Evidence is presented that anti‐Θ sensitive T cells are responsible for the complementation. Experiments are described in which the anti‐sheep red cell response is followed as a function of the number of allogeneic spleen cells used to supplement the nude spleen cell cultures. With increasing numbers of allogeneic cells, optimum complementation is observed and then, a rapid drop of the response as the number of allogeneic cells is increased further. As few as 20 x 103allogeneic spleen cells are able to complement 20 x 106nude spleen cells to give a significant response. A delay in the addition of allogeneic cells up to 24 h does not change the kinetics of the resp

ISSN:0014-2980    

DOI:10.1002/eji.1830030705

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

摘要:

AbstractSheep lymphocytes possessing surface Ig were labeled with125I‐labeled anti‐Ig antibodies. The radioactive complexes thus formed were dissolved from the cell membrane by treatment with the detergent Nonidet‐P40 and their molecular sizes estimated by sedimentation centrifugation. IgG and IgM (20–40 % as 19 S IgM) were shown to be present on the cell surface.Cells labeled with anti‐Ig antibodies and incubated at 37 °C lost 30–40 % of their radioactivity within 30–45 min, after which time the rate of loss decreased. By 3–4 h, approximately 50 % had been released and loss had almost stopped. Label associated with surface‐bound anti‐sheep lymphocyte globulin was also lost rapidly (20–30 % in 30 min), but unlike anti‐Ig antibodies, no further loss occurred. Anti‐Ig complexes retained by labeled cells during incubation at 37 °C were steadily degraded to a 3–4 S component. Sodium azide (0.015 M) significantly reduced the rate at which this degradation occurred (e.g.inhibition relative to degradation in the absence of azide was 94 % after 2 h and 67 % after 4 h incubation, respectively).When unlabeled lymphocytes were incubated at 37 °C for up to 20 h and then reacted with labeled anti‐Ig, the following was observed. The proportions of lymphocytes able to bind anti‐γ or anti‐μ‐chain antibody (as judged by autoradiography) decreased from 17 % to 3 % and 28 % to 18 %, respectively, during 20 h incubation. From measurements of Ig released during incubation, it was concluded that most of the IgG initially on cells binding anti‐γ‐chain antibody was probably cytophilic. IgM initially on the surface of cells binding anti‐μ‐chain antibody seemed to be released and replaced by the cells, al

ISSN:0014-2980    

DOI:10.1002/eji.1830030706

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

摘要:

AbstractRandom bred rabbits were injected with human serum albumin (HA) at birth to induce tolerance to HA. Tolerant animals were then immunized with a p‐azobenzenesulfonic acid derivative of human albumin (HA‐D31). A proportion of these animals, 42 %, (27/64) responded with the production of antibody to HA‐D31(TCR‐responders). Matings were carried out between TCR‐responders and between TCR‐nonresponders, and the offspring were subjected to the same procedures as their parents. Selective breeding of TCR‐responders produced 70 % (12/17) responders after two generations. Selective breeding of TCR‐nonresponders produced only TCR‐nonresponders after the third generation. Fourth generation offspring of TCR‐nonresponders, which were not injected with HA at birth, produced an antibody response to HA‐D31. The specificity of this antibody was analyzed by agglutination‐inhibition tests and was found to be similar to that of antibody produced in unselected rabbits. The genetic control of responsiveness to HA‐D31in HA‐tolerant rabbits

ISSN:0014-2980    

DOI:10.1002/eji.1830030707

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

摘要:

AbstractIt has been shown previously that preparation of F(c)5μ and Fabμ fragments from IgM is limited both by low yields and incomplete cleavage and that digestion with hot trypsin is superior to papain in the absence of cysteine. The present study demonstrates that by using trypsin digestion, F(c)5μ fragment is relatively much more stable than Fabμ fragment. Optimum conditions for splitting with trypsin were 60°C for 20 min.Sedimentation constants of F(c)5μ and Fabμ fragments were 10.9 and 3.7 S, respectively. Molecular weights derived from polyacrylamide disc electrophoresis in sodium dodecyl sulfate were 340 000 and 48 000 for F(c)5μ and Fabμ respectively. The molecular weight of F(c)5μ fragment falls to 33 600 after partial oxidative sulfitolysis.Amino acid and sugar composition of the fragments were determined and accounted for approximately 85 % of the IgM molecule. That portion which was lost is most likely a glycopeptide cleaved from the h

ISSN:0014-2980    

DOI:10.1002/eji.1830030708

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

摘要:

AbstractThe immunosuppressive activity of busulphan, an anti‐tumor agent, was studied using cell‐transfer experiments. Spleen cells from busulphan‐treated donors were many times less active than normal cells, while normal cells could restore competence to busulphan‐treated mice. It was concluded that the drug acts directly upon immunocompetent cells, but has no effect upon the environment in which they work. Further experiments showed that spleen from busulphan‐treated donors did not show synergy with normal marrow or thymus cells, and that neither marrow nor thymus cells from these donors show synergy with the reciprocal normal cell. It was concluded that busulphan affects both thymus‐dependent (T) and thymus‐independent (B) cells. However, marrow alone restored competence to busulphan‐treated recipients which, therefore, must contain an excess of T cells. This may be because mice normally contain an excess of T cells, or because there is a subpopulation of T cells outside the thymus and spleen, unaffect

ISSN:0014-2980    

DOI:10.1002/eji.1830030709

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

摘要:

AbstractResponse to phytohemagglutinin was investigated in adult mouse spleen cells of congenic strains which differ only at the H‐2 locus. The stimulation of spleen cells was assessed by release of lymphotoxins and DNA synthesis.The results obtained show that the response to PHA markedly varied according to the genetic origin of spleen cells. Cells with H‐2aand H‐2bspecificities responded better to PHA than those with H‐2fand H‐2sspecificities. Furthermore, there was good correlation between the amount of released lymphotoxins and the level of DNA synthetic response.These results are discussed on the basis of an H‐2 linked genetic control of PHA response in mo

ISSN:0014-2980    

DOI:10.1002/eji.1830030710

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

摘要:

AbstractThe cell‐mediated lympholysis (CML) technique has been used to investigate antigenic strength in mice. Investigations of the parameters of the technique led to calculation of specific chromium release on the basis of the effect of 5‐day mixed lymphocyte cultures (MLC) incubated for 4 h with 3‐day51Cr‐labeled phytohemagglutinin (PHA) transformed blast cells in a ratio of 50:1.The specificity of the reaction was established in mirror experiments and both major histocompatibility locus and M‐locus (non H‐2) incompatible MLC were tested against the appropriate PHA blasts. While strong MLC stimulation occurred in both these types of incompatible combinations, a specific killing capacity for CML developed only in the former. Furthermore, M‐locus gene productsper sedo not seriously influence the outcome of allograft survival a result consistent with those of others working in the rat and man, in which species the capacity to respond in MLC and to kill in CML and/or to reject allografts can be separated.The fact that M‐locus stimulation does not lead to cell killing could be due to the absence of a concomitant serologically defined incompatibility; if so, the serologically undetectable lymphocyte activating determinants of the major histocompatibility system linkage group could have a similar biological function to that

ISSN:0014-2980    

DOI:10.1002/eji.1830030711

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY