摘要:

AbstractT and B cells continually migrate around the body by recirculating between blood and lymph via lymphoid tissues. This is an important way of fostering the cell‐cell interactions required for the initiation of an immune response. Data from previous studies of T and B cell recirculation, based on relatively complex approaches, have been interpreted as evidence that the recirculation of B cells is more sluggish than for T cells. We have shown from a study in sheep that this is not the case. Lymphocyte migration through both the intestine and the prescapular lymph node was analyzed by cannulating efferent lymphatics. The lymph cells were labeledin vitrowith Hoechst 33342, or other fluorochromes, then injected i.v., and the rate of their recirculation into the lymph was determined by fluorescence microscopy. A multicolor immunofluorescence assay was used to classify each recirculated cell as either a T or B cell. This established that the T and B cells from intestinal lymph and from prescapular lymph recirculate with similar kinetics. The recovery of i.v. injected T and B cells was the same in prescapular lymph, but fewer injected B cells than T cells were recovered in intestinal lymph. Thus, although the recirculation kinetics are the same for T and B cells, the two populations are handled differently in intestinal tissues and a lymph node remote from the gu

ISSN:0014-2980    

DOI:10.1002/eji.1830180602

出版商:WILEY‐VCH Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractWe have studied the expression and sequences of T cell receptor γ and δ chain gene messages in intrathymic T cell precursors of mice irradiated with 600 rads. On day 7 after irradiation a high level of expression of γ and δ chain messages was detected in thymocytes which were composed of a relatively high proportion of CD3+CD4−CD8‐thymocytes. During further development of the precursors from day 7 to day 14 after irradiation, γ and δ chain messages fell to low levels and α and β mRNA levels increased. Nucleotide sequence analysis of 14 γ and 10 δ chain complementary DNA (cDNA) in the thymocytes on day 7 revealed that there were 7 functional γ chain transcripts composed of Vγ2‐Jγ2‐Cγ2 or Vγ1‐Jγ4‐gene segments, and only 1 functional δ chain transcript composed of the VδM23‐Dδ1‐Dδ2‐Jδl‐Cδgene segments. The repertoire of γ chain and δ chain genes used in “radioresistant” intrathymic T cell

ISSN:0014-2980    

DOI:10.1002/eji.1830180603

出版商:WILEY‐VCH Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractTo identify the molecular localization and specificity ofMycobacterium lepraeantigenic determinants inducing T cell activation, we studied the reactivity ofM. leprae‐reactive T cell clones from two tuberculoid leprosy patients towards a battery of different mycobacterial strains and purified mycobacterial antigens. Of the 38 T cell clones tested 8 appeared to beM. lepraespecific (specificity A), another 8 were cross‐reactive with at least one of the three mycobacterial strains,M. lepraemurium, M. vaccaeandM. scrofulaceum(specificity B), 5 were reactive with most but not all strains (specificity C) and the remaining 18 were reactive with all 17 mycobacterial strains tested (specificity D), but not with nonmycobacterial antigens. All T cell clones were tested with the 36K and 65K antigen isolated fromM. leprae, and with theM. lepraeandM. bovisBCG 65K proteins produced inE. coliby recombinant DNA. Four T cell clones appeared to recognize epitopes on the 36K antigen, nine T cell clones recognized the 65K antigen. These 2M. lepraeantigens, 36K and 65K, thus seem to contain major T cell epitopes. At least 3 different epitopes could be defined on the 36K antigen of which one isM. lepraespecific, one of specificity B and one of specificity C. Two distinct epitopes were discerned on the 65K antigen of which one isM. lepraespecific and one of specificity D. TheM. leprae‐specific epitopes on the 36K and 65K antigen may help in the development of a specific serodiagnostic and skin

ISSN:0014-2980    

DOI:10.1002/eji.1830180604

出版商:WILEY‐VCH Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractAn oligonucleotide probe corresponding to nucleotides of a cDNA encoding the T cell‐associated proteinase 1 (TSP‐1) was chosen to study the induction and expression of TSP‐1‐specific transcripts in mouse T lymphocytes and tissues. We demonstrate that TSP‐1 mRNA is only expressed in activated T lymphocytes and is absent from all mouse tissues tested including those containing resting mature T lymphocytes. Expression of the TSP‐1 gene was observed in T lymphoctesin vitroin response to either phorbolester (phorbol 12‐myristate 13‐acetate), Ca2+ionophore (A23187), lectin or alloantigen. In general, TSP‐1 mRNA appeared and peaked later compared to interleukin 2 transcripts. Furthermore, TSP‐1 mRNA was induciblein vitroin both Ly‐2+and L3T4+lymphocyte populations treated with alloantigen and/or lectin. The transcription of the TSP‐1 gene was always accompanied by the expression of proteinase activity. High expression of TSP‐1 transcripts was also observed inin vivoderived T effector cells specific for lymphocytic choriomeningitis virus. However, TSP‐1 mRNA was predominantly associated with virus‐specific Ly‐2+T cells and correlated with their proteinase and cytolytic activities. The data suggest that TSP‐1 gene transcription is a useful marker to characterize T

ISSN:0014-2980    

DOI:10.1002/eji.1830180605

出版商:WILEY‐VCH Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractStromal cells which grow as an adherent layer of Whitlock‐Witte cultures are thought to be an essential component of the lymphohemopoietic microenvironment. Stromal cell lines from bone marrow (BM) and spleen have been obtained by treatment of cultures with 5fluorouracil and selected for their lymphocyte support capacity by measuring the clonal growth of stromal cell‐dependent lymphocyte lines in methyl cellulose.Established stromal cell lines differed significantly from stromal cells in primary Whitlock‐Witte cultures with respect to expression of certain hemopoietic cell surface markers. For example, the Thy‐1 and Mac3 antigens were expressed by stromal cell lines obtained from BM and spleen, but not by stromal cells in primary cultures. Features common to all stromal cells include synthesis of actins, the neural adhesion molecule N‐CAM, and a variety of collagens. Two types of common leukocyte antigens were not significantly expressed.The proliferation and total protein synthetic capacity of lymphocyte‐supportive stromal cell lines was sensitive to ionizing radiation. After exposure of the cells to 200 rads, the incorporation of either [3H]thymidine or [3H]Leucine was reduced to less than 50% of control values, but the growth of lymphocytes was augmented in the presence of an irradiated stromal cell layer.The proliferation of stromal cell lines was also affected by exposure to a variety of growth factors. Addition of epidermal growth factor or endothelial cell growth factor augmented BM or spleen‐derived stromal cell proliferation, while interferon‐γ had the opposite effect. In general, but not exclusively, lymphocyte growth was inhibited by factors which augmented the proliferation of stromal cells.Novel methods are described for isolating stromal cells and determining their capacity to support lymphocyte growthin vitro.Evidence is presented that this ability is not restricted to BM‐derived stromal cells. The function of stromal cells was not dependent on their ability to proliferate, and this may be modulated by immunoregulatory and ot

ISSN:0014-2980    

DOI:10.1002/eji.1830180606

出版商:WILEY‐VCH Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractThe T cell receptor (TcR) for antigen is composed of variable α and β subunits in noncovalent association with the invariant T3 multimer. TcR/T3 transcripts accumulate in a specific sequence during T cell development; TcR α transcripts are the last in the series to accumulate. To explore the regulation of TcR α gene expression, we investigated a T lymphoma cell clone which constitutively expresses TcR β, T3 † and T3 e mRNA, but essentially lacks detectable TcR α mRNA. The cell clone can be induced to accumulate substantial amounts of TcR α mRNA in response to phorbol myristate acetate (PMA) or calcium ionophore A23187. Two different protein synthesis inhibitors also induce TcR α mRNA. The following evidence indicates that PMA, A23187 and cycloheximide induce TcR α by different mechanisms: (a) treatment with a combination of two agents induces greater than additive amounts of TcR a mRNA than that induced by a single agent; (b) the immunosuppresent cyclosporin A specifically inhibits A23187‐mediated TcR α mRNA induction, whereas it fails to inhibit PMA or cycloheximide‐mediated induction; and (c) both A23187 and PMA increase the rate of TcR α gene transcription, while cycloheximide influences TcR α mRNA accumulation by post‐transcr

ISSN:0014-2980    

DOI:10.1002/eji.1830180607

出版商:WILEY‐VCH Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractAlterations in the progression of the inflammatory disease in mice with established collagen‐induced arthritis (CIA) byin vivotreatments with either anti‐T cell antibodies or an immunosuppressive drug, whose main targets of action are T cells, were studied. It was demonstrated that thein vivoadministration of either monoclonal anti‐L3T4, anti‐Ly‐2 or the combination of anti‐L3T4 and anti‐Ly‐2 failed to modify the inflammatory disease after the arthritis had been initiated. Nevertheless, the progression of disease was decreased by treatments with rabbit anti‐mouse lymphocyte sera (ALS) in mice with established CIA. While there was a substantial reduction in the proliferative responses to the T cell mitogen concanavalin A (Con A) in these ALS‐treated mice, proliferation to a B cell mitogen, lipopolysaccharide, was unaffected. Furthermore, treatments with anti‐Thy‐1.2 monoclonal antibody (mAb) by itself did not alter the progression of the ongoing inflammatory disease, but combined treatments with both anti‐Thy‐1.2 and anti‐L3T4 mAb prevented the further advancement of the arthritic disease. Although mice receiving either anti‐Thy‐1.2 alone or both anti‐Thy‐1.2 and anti‐L3T4 exhibited complete absence of Thy‐1+cells within their inguinal lymph nodes, the proliferative responses to Con A by LN cells from mice treated with the combination of anti‐Thy‐1.2 and anti‐L3T4 were drastically reduced compared to the responses of either the anti‐Thy‐1.2 or anti‐13T4‐treated groups. Finally, daily treatments with cyclosporin A, an immunosuppressive drug which preferentially acts on T cells, were also effective in modifying the clinical course of the arthritic disease in mice with established CIA. These results suggest that immunocompetent cells which express the Thy‐1 surface marker, most likely Thy‐1+T cells, may play a role in maintaining a

ISSN:0014-2980    

DOI:10.1002/eji.1830180608

出版商:WILEY‐VCH Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractPartial characterization and frequency determination of the progenitors for thymic T cells in various organs were made b transferring cells directly into the thymus (intrathymically, i.t.). B0.Thy‐1.1 (H‐2b, Thy‐1.1) mice were used as the donor, and C57BL/6 (H‐2b, Thy‐1.2) mice that had been whole body irradiated with 800 rads and reconstituted with 107syngeneic (B6) bone marrow (BM) cells were used as the recipient. BM cells, spleen cells and thymus cells from young adults and fetal liver cells (day 14 of gestation) were treated with anti‐Thy‐1.1 antibody plus complement, and trasferred i.t. The generation of Thy‐1.1+donor type cells in the recipient's thymus was investigated by using flow cytometry. From the time course of generation, it was shown that the progenitor cells in the thymus were distinct from those in other organs. After the transfer of thymic non‐T cells, donor‐type cells began to generate on the 4th day, the proportion of donor‐type T cells increased quickly thereafter, and the progenitors in this organ ceased to produce T cells by day 21. On the other hand, a latent period of about 10 days was required for progenitor cells in the BM, spleen or fetal liver to generate T cells, and T cell producing‐activity of the progenitor cells in these organs lasted as long as 7 weeks.The frequency of progenitor cells was analyzed by transferring serial dilutions of anti‐Thy‐1.1 plus complement‐treated cells i.t. and investigating the generation of donor‐type T cells in the recipient's thymus on day 11 in the case transferred with thymic cells and on day 21 in other cases. The proportion of negative recipients which did not contain detectable levels of donor‐type cells was plotted on a logarithmic scale against the number of cells transferred on a linear scale. The progenitor cell frequencies in BM, spleen, thymus and fetal liver were estimated to be 12.5 × 10−5, 6.25 × 10−5, 0.22 X10−5and 0.14 × 10−5, respectively. The reliability of the frequency determination was supported by the finding that when a limited number (103) of a 1:1 mixture of BM cells from two mutually identifiable donors was transferred it., most of the recipients were negative for donor‐type T cells and 3 out of 4 positive recipients wer

ISSN:0014-2980    

DOI:10.1002/eji.1830180609

出版商:WILEY‐VCH Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractFunctions of T cells derived from single progenitor cells were investigated. B10. Thy‐1.1 recipient mice were either whole body‐irradiated and marrow reconstituted or thymus‐shielded, irradiated and marrow reconstituted, and limited numbers (3 × 103or 6 × 103) of a 1:1 mixture of bone marrow cells from C57BL/6 and B6.Lyt‐2.1 mice were transferred intrathymically (i.t.). Donor‐type (Thy‐1.2+) cells of the thymus of a small portion of recipients which expressed the phenotype of either Ly‐2.2 or Ly‐2.1 but not both were regarded to be a clone of T cells derived from a single progenitor cell, and such clones were assayed for polyclonal helper (Th) and polyclonal cytolytic (CTL) activities as well as alloantigen‐specific proliferative (mixed lymphocyte reaction; MLR) and CTL activities. Clones taken 4 weeks after transfer (4‐week‐old clones) which were generated in the thymus of whole body‐irradiated recipients showed polyclonal CTL but not polyclonal Thactivity, whereas 4‐week‐old clones generated in the thymus of thymus‐shielded recipients showed both polyclonal CTL and Thactivities. Similarly, 4‐week‐old clones generated in whole body‐irradiated recipients responded with CTL to alloantigens when induced in the presence of T cell growth factors but not with MLR, whereas 4‐week‐old clones generated in thymus‐shielded recipients showed both MLR and CTL to alloantigens. Repertoire difersifi‐cation of 4‐week‐old clones, however, was incomplete, since clones generated in whole body‐irradiated recipient did not necessarily respond with CTL to all alloantigens examined, and those generated in thymus‐shielded recipients did not necessarily respond with MLR to all the antigens. On the other hand, T cell clones were shown to fully mature by 7 weeks after transfer in terms o

ISSN:0014-2980    

DOI:10.1002/eji.1830180610

出版商:WILEY‐VCH Verlag GmbH    

年代:1988

数据来源: WILEY

摘要:

AbstractA human IgE‐producing myeloma has been cultivatedin vitroas a continuous cell line (U‐266) since 1968. Analysis of immunoglobulin production during early passages of the cell line demonstrated a high synthesis rate of monoclonal IgE. Analysis of late passages, cultivated after 1980, revealed a 3‐6‐fold lower rate of IgE secretion, This decrease was accompanied by the appearance of small amounts of IgA in the culture medium together with IgE. RNA was extracted from a late passage of U‐266 and analyzed by Northern blotting, using ϵ and α‐specific oligonucleotides as hybridization probes. The results showed the presence of ϵ as well as α‐specific mRNA. Moreover the results demonstrated that the latter mRNA was derived from the α2 locus and that the ϵ and the α2‐specific mRNA contained the same V region sequences. Southern blot analysis of DNA from the late passage of the U‐266 cell line failed to reveal a recombinatory switch from the ϵ locus to the α2 locus. The expression of α2 is thus likely to be caused by differential splicing rather than by an isot

ISSN:0014-2980    

DOI:10.1002/eji.1830180611

出版商:WILEY‐VCH Verlag GmbH    

年代:1988

数据来源: WILEY