摘要:

AbstractEvidence has been presented to show that chemokinesis and chemotaxis of human neutrophil granulocytes can be controlled by distinct cellular mechanisms and by different chemicals. Materials such as human serum albumin or fibrinogen had chemokinetic but no chemotactic properties. Highly purified preparations of serum‐derived peptides containing classical anaphylatoxin had detectable chemotactic activity only. Chemokinetic as well as chemotactic substances were required for the expression of chemotaxis in the form of efficient directional locomotion. The roles of chemokinesis and chemotaxis in the regulation of directional locomotion have been analyzed.Further experiments showed that the chemotactic response conforms to the law of Weber‐Fechner. The number of cells which had accumulated in response to a chemotactic stimulus was proportional to the logarithm of the concentration of the chemical substance. Readaptation from high to low chemotactic stimulus intensities occurred only to a limited ext

ISSN:0014-2980    

DOI:10.1002/eji.1830080102

出版商:WILEY‐VCH Verlag GmbH    

年代:1978

数据来源: WILEY

摘要:

AbstractWe studied the function of fetal thymocytes, derived from thymus progenitor cells of 14‐day‐old fetuses in an organ culture system, in anin vitrohumoral immune response. The unprimed cultured fetal thymocytes suppressed the T‐dependent primary immune response of adult syngeneic spleen cells against sheep red blood cells, but failed to suppress the response against the T‐inde‐pendent antigen NIP‐POL [4(hydroxy‐3‐iodo‐5‐nitrophenyl)acetyl‐coupled polymerized flagellin]. The suppression was abolished by anti‐Thy‐l serum and complement treatment. Using a differential killing procedure, the suppressor cells were characterized as “low” Thy‐1 cells. In addition, they were resistant to hydrocortisone. Suppression could only be achieved when the cultured fetal thymocytes were added during the first 48 h of culture, suggesting that their action occurred during the induction phase of the response. The implications of the high frequency of suppressor cells

ISSN:0014-2980    

DOI:10.1002/eji.1830080103

出版商:WILEY‐VCH Verlag GmbH    

年代:1978

数据来源: WILEY

摘要:

AbstractPrecursor analysis of the function of murine B cells with surface IgD has been accomplished using an alloantiserum directed against a δ allotype and cellular affinity chromatography. Spleen cells from 3‐week‐old C57BL.Igemice were treated with a TNP‐labeled anti‐δ allotype serum, washed and passed through an anti‐TNP affinity column. The cells passing such a column were depleted of IgD‐bearing lymphocytes by immunofluorescence and also showed a greatly reduced ability to develop into specific antibody‐forming cell clonesvs.the fluorescein (FL) hapten in a limiting dilution microculture systemin vitro.In contrast, the IgD‐bearing cells eluted from such columns were slightly enriched in precursor activity compared to the original population. Moreover, brief treatment with anti‐δ serum alone produced a partial reduction in the precursor frequencyvs.FL with C57BL.Igespleen cells (which bear the appropriate δ allotype) but not C57BL/6 spleen cells (which are negative for this δ allotype). This effect varied with the age of the spleen donor, but was most dramatic with splenocytes from 2 to 3‐week‐old mice. This contrasts with the effect of anti‐pi pretreatment, which only inhibited neonatal precursors. The results are interpreted in terms of the maturation of murine B cells and the function of IgD and IgM receptors in t

ISSN:0014-2980    

DOI:10.1002/eji.1830080104

出版商:WILEY‐VCH Verlag GmbH    

年代:1978

数据来源: WILEY

摘要:

AbstractThis report describes model systems which show low primaryin vitrosyngeneic cytotoxic responses to a Moloney‐induced YAC tumor (syngeneic in A mice) and a Rauscher‐induced RBL5 tumor (syngeneic in C57BL/6 mice) and examines different approaches to overcome these defects.Two major findings were obtained: (a) spleen cells from A mice, injected with tumor cells from anin vitrotumor line YAC‐1, derived from YACL, could generate a significant syngeneic cytotoxic response. In contrast, spleen cells from A mice injected with tumor cells from thein vivotumor line failed to generate a syngeneic cytotoxic response. Thus, tumor cells from thein vitroline were more immunogeneic that those from thein vivoline. (b) Spleen cells from A mice which were injected with the crossreactive allogeneic tumor RBL5, could generate significant cytotoxic responses to the syngeneic tumors YAC and YAC‐1. Similarly, spleen cells from C57BL/6 mice injected with the cross‐reactive allogeneic tumor YAC‐1, could generate a significant cytotoxic response to the syngeneic tumor RBL5. Thus, cross‐reactive allogeneic tumors could stimulate syngeneic cytotoxicity. The theoretical and the practical implications of these studies

ISSN:0014-2980    

DOI:10.1002/eji.1830080105

出版商:WILEY‐VCH Verlag GmbH    

年代:1978

数据来源: WILEY

摘要:

AbstractRetinoic acid (RA), a vitamin A derivative with anti‐tumor activity, was assayed for its effects on the immune system in mice. High doses of this compound (1000 μg/mouse/day) have toxic effects and cause depletion of the peripheral lymphoid organs (spleen, thymus) while leaving the bone marrow cells unaffected. Both thein vivoandin vitroinduction of cell‐mediated cytotoxicity (CMC) to allogeneic tumor cells is stimulated at least tenfold by low doses (25–300 μg/mouse/day) of RA while high doses suppress CMC induction. RA is shown to be a specific adjuvant for the induction of cytotoxic thymus‐derived lymphocytes (T cells) and not a general T cell mitogen or adjuvant. It does not enhance the proliferative response in the mixed lymphocyte culture nor does it stimulate lymphocyte proliferation in response to the mitogens concanavalin A and phytohemagglutinin. The induction of cooperating T cells and the delayed‐type hypersensitivity reaction are also not stimulated by RA. In contrast to the reported stimulatory effects of retinyl palmitate and retinyl acetate, RA does not stimulate the humoral response to erythrocytes. The strong adjuvant effects that RA has on the induction of CMC at low doses may be responsible for its anti‐t

ISSN:0014-2980    

DOI:10.1002/eji.1830080106

出版商:WILEY‐VCH Verlag GmbH    

年代:1978

数据来源: WILEY

摘要:

AbstractWe have investigated the sequential interaction of macrophages, initiator T lymphocytes (ITL) and recruited T lymphocytes (RTL) in the development of a T cell‐mediated response to soluble antigens. Macrophages were pulsed with soluble antigens and used to sensitize ITLin vitro.The ITL were irradiated to prevent their proliferation and then injected into the footpads of syngeneic mice. Sensitized ITL were found to recruit immunospecific RTL in the draining lymph nodes, as determined by a thymidine uptake assay of the lymph node cellsin vitro.The richest source of lymphocytes with ITL activity was the thymus, and progressively less activity was detectable among spleen or lymph node lymphocytes. The magnitude of the subsequent RTL response could be modified by genetic differences between the ITL and the antigen‐pulsed macrophages that were used to sensitize them. Thus, ITL conveyed an immunogenic signal to RTL whose magnitude reflected the genotype of the macrophages, but whose specificity was directed by determinants of the soluble anti

ISSN:0014-2980    

DOI:10.1002/eji.1830080107

出版商:WILEY‐VCH Verlag GmbH    

年代:1978

数据来源: WILEY

摘要:

AbstractIn previous studies we found that the generation of a cell‐mediated immune reaction required interaction between sensitized initiator T lymphocytes (ITL) and syngeneic recruited T lymphocytes (RTL). ITL were sensitizedin vitroagainst allogeneic mouse fibroblasts and injected into a footpad of syngeneic recipient mice. ITL were observed to migrate from the connective tissues of the footpad to the draining popliteal lymph node (PLN). Sensitized ITL recruited RTL from the blood circulation into the PLN. This recruitment led to the generation of immunospecific effector and memory lymphocytes.In the present study we investigated the cellular characteristics of ITL and RTL. We found that both ITL and RTL were positive for Thy‐1 antigen, and were absent from B mice. However, ITL and RTL differed in their response to various treatments. ITL were sensitive to adult thymectomy and resistant to antithymocyte serum (ATS). RTL were resistant to adult thymectomy and sensitive to ATS. Sensitized ITL were adherent to nylon wool or histamine‐rabbit serum albumin‐Sepharose, while RTL were not retained on such columns.ITL and RTL also differed in their relative distributions in various lymphoid organs and migratory pathways. The thymus demonstrated ITL but not RTL activity. In contrast, lymph node lymphocytes were a rich source of RTL, but had no detectable ITL activity. Both ITL and RTL could be demonstrated in the spleen. Thus, ITL and RTL functions are mediated by distinct subclasses of T lymphocytes which reside in particular compartments of the immune

ISSN:0014-2980    

DOI:10.1002/eji.1830080108

出版商:WILEY‐VCH Verlag GmbH    

年代:1978

数据来源: WILEY

摘要:

AbstractThe variable portion of the light chain (VL) of protein 315 was studied as a model for antibody composed of two “like” chains. VLexists as a dimer which contains the binding subsite for the dinitrophenyl (Dnp) ring of Dnp ligands. Circular dichroism analysis of hapten‐protein complex demonstrated that the geometry of the Dnp hapten in the (VL)2binding site is different from that in the Fv (composed of VL–VH) site. The VLdimer was found to be present in two distinct, pH‐dependent conformations which differ markedly in their binding properties. At pH 8.0 VLdimer binds two Dnp‐lysine per dimer, whereas at pH 6.0 only one ligand is bound per (VL)2. The association constant of (VL)2for Dnp‐L‐lysine at pH 6.0 is 3–4‐fold higher than that at pH 8.0. The geometry of the hapten in the combining site is also different in the two conformers of (VL)2as can be judged from the disappearance at pH 6 of the 480 nm and 390 nm absorbance bands in the difference spectrum of VL‐bound Dnp‐caproate. The pH‐dependent changes in the difference spectra between bound and free ligands were used to follow the transition between the two conformers of VLdimer. It was concluded that the pKa of this transition is at pH 6.9. The change in VLconformation is also expressed in a 2–3‐fold enhancement of VLfluorescence between pH 6 and pH 8, suggesting that the conformation at pH 8 which binds two ligands is more open, whereas at pH 6 a more tight conformation exists, binding one ligand with higher affinity. Such changes were not observed with Fv which is composed of both VLand VH‐These data suggest that an antibody site composed of two like chains (VL–VL) can undergo marked conformational changes at physiological pH values. The relevance of this finding to problems of receptors on thymus

ISSN:0014-2980    

DOI:10.1002/eji.1830080109

出版商:WILEY‐VCH Verlag GmbH    

年代:1978

数据来源: WILEY

摘要:

AbstractProtein A fromStaphylococcus aureus, in soluble form or coupled to Sepharose beads, acts as a polyclonal B cell activator (PBA) for human lymphocytes in blood and spleen.PBA activity was demonstrated in spleen cells by the ability of protein A to induce the formation of intracellular immunoglobulin synthesis and to activate polyclonal antibody secretion demonstrated against fluorescein isothiocyanatecoupled sheep erythrocytes in a modified hemolysis in gel assay. More plaqueforming cells (PFC) were seen in unseparated cells than in purified B cells. In blood lymphocytes, only few PFC were activated by soluble protein A.Protein A increased DNA synthesis in blood and spleen cells. At a concentration of 100 μg/ml the peak response was on day 4 or 5, but at 1 μg/ml the peak response occurred later. On day 4 of culture, high mitogenic activity was seen in unseparated lymphocytes or mixtures of separated B and T cells, whereas in enriched B and T cell suspensions activity was low. On day 7, however, DNA synthesis in both the enriched B and T cells was higher than in mixtures of B and T cells. Protein A stimulated DNA synthesis in thymus cells with a peak response on day 6. It is concluded that protein A alone or as an IgG complex can activate both B and T cells, though the mechanism of activation is not known and may be different for B and T cell

ISSN:0014-2980    

DOI:10.1002/eji.1830080110

出版商:WILEY‐VCH Verlag GmbH    

年代:1978

数据来源: WILEY

摘要:

AbstractMice genetically selected for high (Ab/H) or low (Ab/L) humoral antibody responses were infected withSchistosoma mansoniin order to assess the role of antibodies in innate and acquired immunity to this parasite. Ab/H mice produced higher levels of humoral antibodies to schistosome antigens, but were more susceptible to infection than Ab/L mice. This was shown by the higher number of parasites recovered from Ab/H mice, by the larger size of the parasites themselves, by the number of schistosome eggs and their rate of deposition in the host liver. In addition, Ab/L mice could develop an acquired resistance to schistosome re‐infection which was as good as, or possibly even better than the resistance developed by Ab/H mice. These findings suggest that humoral antibodiesper semay not play a critical role in schistosome immunity, and at the same time call attention to the possible importance of macrophages in determining the results observe

ISSN:0014-2980    

DOI:10.1002/eji.1830080111

出版商:WILEY‐VCH Verlag GmbH    

年代:1978

数据来源: WILEY