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51.
Irradiated LCL cells from several sources activated the blood lymphocytes of a panel of donors. Individual differences were present but were small. Stimulated blood lymphocytes were more potent activators (after X-irradiation) than small lymphocytes in a one-way mixed lymphocyte reaction, indicating that the state of metabolic activity of the `stimulating' lymphocyte affects the level of activation achieved. However, LCL cells incubated for several days after irradiation had not lost stimulatory capacity. Lymphocytes of pigs, rabbits, rats and mice were much less responsive than human lymphocytes. The response of animal lymphocytes generally varied with the species of origin of the serum used in the cultures.  相似文献   
52.
Properties of T cells from inflammatory lesions were analysed by comparing the response of peripheral blood (PB) and synovial fluid (SF) T cells from 19 patients with a range of arthropathies to enriched allogeneic dendritic cells (DC) in a primary mixed leucocyte reaction (MLR). In 17 patients the proliferative response of SF T cells was significantly (P less than 0.05) less than that of PB lymphocytes. The reduced response of SF T cells was observed in all disease categories studied and could not be attributed to differences in cell number requirements or response kinetics. Addition of recombinant interleukin-2 enhanced the response of SF T cells in a dose-dependent manner. Cell mixing experiments suggested that active suppression was not the underlying mechanism of the poor MLR response of SF T cells. In contrast to the MLR response. SF T cells were able to mount vigorous proliferative responses to recall antigen presented by autologous antigen-presenting cells. The possibility is discussed that T cells compartmentalized at inflammatory lesions are a unique population with a diminished ability to interact with DC and respond to primary stimuli but an ability to respond to secondary antigenic challenge.  相似文献   
53.
This study investigated whether the high expression of adhesion molecules on enriched preparations of circulating dendritic cells (DCs) was an intrinsic property of the cells or whether it was a consequence of the procedure used to isolate them from blood. Expression of the beta 1, beta 2 integrins (CD11/CD18 family) and other adhesion molecules on DCs in whole blood was compared with that on isolated DCs. Dendritic cells were identified by flow cytometry as leucocytes that were positive for human leucocyte antigen (HLA)-DR, but negative for CD3, CD14, CD16, CD19 and CD56. In contrast to a minority of DCs in whole blood, the majority of isolated DCs expressed the beta 2 integrins and there were a greater number of cells bearing CD44, CD54 and some of the beta 1 integrins (notably CD49b, CD49d, CD49e and CD29). An increase in the proportion of DCs bearing adhesion molecules was generally apparent at the isolation stage when mononuclear cells, which had been incubated overnight, were centrifuged on a metrizamide gradient to enrich for cells of low density. Inclusion of an inhibitor of protein glycosylation and exocytosis (brefeldin A) at all stages of separation partially prevented an increase in the percentage of DCs bearing CD18, C29 and C54 whereas the inclusion of cycloheximide (an inhibitor of polypeptide synthesis) interfered with increases in the percentage of cells bearing CD29 and CD54. Neither of these antagonists had an effect on the intensity of adhesion molecule expression. We suggest that some of the adhesion-dependent functions of isolated DCs are caused, in part, by an upregulation of surface adhesion molecules induced by the enrichment procedure.  相似文献   
54.
The response of human, rabbit and guinea-pig thymocytes in culture to blastogenic stimulants such as phytohaemagglutinin (PHA) and staphylococcal filtrate (SF) was usually considerably less than that seen with equivalent numbers of peripheral blood and lymph node lymphocytes.  相似文献   
55.
Rapid identification and differentiation of orthopoxviruses by PCR were achieved with primers based on genome sequences encoding the hemagglutinin (HA) protein, an infected-cell membrane antigen that distinguishes orthopoxviruses from other poxvirus genera. The initial identification step used a primer pair of consensus sequences for amplifying an HA DNA fragment from the three known North American orthopoxviruses (raccoonpox, skunkpox, and volepox viruses), and a second pair for amplifying virtually the entire HA open reading frame of the Eurasian-African orthopoxviruses (variola, vaccinia, cowpox, monkeypox, camelpox, ectromelia, and gerbilpox viruses). RsaI digest electropherograms of the amplified DNAs of the former subgroup provided species differentiation, and TaqI digests differentiated the Eurasian-African orthopoxviruses, including vaccinia virus from the vaccinia virus subspecies buffalopox virus. Endonuclease HhaI digest patterns distinguished smallpox variola major viruses from alastrim variola minor viruses. For the Eurasian-African orthopoxviruses, a confirmatory step that used a set of higher-sequence-homology primers was developed to provide sensitivity to discern individual virus HA DNAs from cross-contaminated orthopoxvirus DNA samples; TaqI and HhaI digestions of the individual amplified HA DNAs confirmed virus identity. Finally, a set of primers and modified PCR conditions were developed on the basis of base sequence differences within the HA genes of the 10 species, which enabled production of a single DNA fragment of a particular size that indicated the specific species.  相似文献   
56.
Gammadelta T cells are expanded in human IgA nephropathy and in a rat model of adriamycin (ADR)-induced nephropathy. Despite different diseases and species, these renal gammadelta T cells use a restricted set of gammadelta T cell receptor (TCR) genes. To explore whether this phenomenon of post injury expansion of gammadelta T cells occurs in autoimmune-mediated glomerulonephritis, we studied gammadelta TCR genes in Heymann nephritis (HN). Gammadelta T cells were increased in HN kidneys (p<0.001). These gammadelta T cells predominantly expressed Vgamma6/Vdelta1 genes and used canonical matching sequences previously seen in the other models of renal injury. Gammadelta T cells from the kidneys expressed high levels of TGF-beta, IL-4 and IL-5. The gammadelta T cells from both ADR-treated and HN kidneys expressed NKG2D, the NK cell-activating receptor. These results demonstrate that the majority of gammadelta T cells in the HN kidney use a canonical Vgamma6/Vdelta1 TCR--the gammadelta TCR previously described in the rat ADR-treated kidney. The restriction in gammadelta TCR seen in two completely different models of kidney injury and the expression of an innate activating molecule NKG2D suggests that the gammadelta T cells may be responding to tissue stress from injury and producing a regulatory response.  相似文献   
57.
In earlier studies, primary proliferative and cytotoxic T-cell (CTL) responses to influenza virus were produced in vitro by using mouse dendritic cells (DC) pulsed with virus or viral peptide as the stimulus for syngeneic T cells in 20-microliters hanging-drop cultures. We have now adapted this system for producing primary responses with cells from non-immune donors to produce primary proliferative and CTL responses to human immunodeficiency virus I (HIV) and to HIV peptides in vitro using cells from normal human peripheral blood. All donors in this study were laboratory personnel with no history of HIV infection. DC enriched from peripheral blood were exposed to HIV in vitro and small numbers were added to T lymphocytes in 20-microliters hanging drops. Proliferative responses to virus-infected DC were obtained after 3 days in culture. After 6 days, CTL were obtained that killed virus-infected autologous--but not allogeneic--phytohaemagglutinin (PHA)-stimulated blast cells. Proliferative and CTL responses were obtained using cells from 14 random donors expressing a spectrum of major histocompatibility complex (MHC) types but the CTL, once produced, showed killing restricted by the MHC class I type. Treatment of cultures with monoclonal antibody (mAb) to CD4-positive cells at the beginning of culture blocked the development of both proliferative and CTL responses, but treatment after 5 days had no effect on the CTL activity. Treatment with MCA to CD8-positive cells at the beginning of culture did not block proliferation significantly, but treatment either before or after the 5-day culture period blocked CTL responses. Collaboration between proliferating CD4-positive cells and CD8-positive cells may thus be required to produce CTL of the CD8 phenotype. DC exposed to HIV also produced CTL that killed autologous blast cells pulsed with gp120 envelope glycoprotein. However, DC infected with whole virus did not produce CTL that lysed target cells pulsed with a synthetic peptide, which included a known T-cell epitope of gp120 (representing amino acids 111-126). DC pulsed with gp120 were a poor stimulus for the development of CTL. In contrast, DC pulsed with the peptide (111-126) stimulated both proliferative and CTL responses. The latter killed not only target cells pulsed with the peptide itself or with gp120 but also killed virus-infected autologous blast cells. CTL were again obtained reproducibly with this peptide using donors expressing a spectrum of MHC types.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
58.
Lymphocyte Stimulation   总被引:1,自引:0,他引:1  
  相似文献   
59.
The patient presented with the typical features of Down syndrome: hypotonia, brachycephaly, flattened occiput, bilateral prominent medical epican-thic folds, flat nasal bridge, protruding tongue, low-set dysplastic ears, short broad hands, bilateral clinodactyly and simian crease. The karyotype of this child was originally reported as normal. High-resolution chromosomes revealed extra material on the long arm of chromosome 18. The mother's karyotype showed a reciprocal translocation between the long arm of 18 and the long arm of 21 at band q23 and q22.1, respectively. FISH performed separately with two different 21q cosmid probes gave two signals on the mother's metaphases and three signals on the prob-and. These findings confirmed that the proband is trisomic for the long arm of chromosome 21 at loci D21S65 and D21S19.  相似文献   
60.
A pilot study is reported of HLA-A, B, and C antigens in 141 East African Blacks comprising patients with Burkitt's lymphoma or nasopharyngeal carcinoma, either with active disease or in long-term remission, together with comparable controls. This study forms part of a wider program investigating host factors in these diseases. A protocol was selected for optimal testing of cells processed and cryopreserved between 1972 and 1976, largely under field conditions, which employed a two-color fluorochromasia typing procedure. Antigen distribution and computed haplotype frequencies in the total unrelated population are given. New findings include an approximately equal frequency of Aw23 and Aw24, a high (18%) incidence of Bw21, and the gametic associations of Aw36 with Bw44, and Aw30 with Bw45. Of the major group of B15-related antigens reported earlier, SV is the most common, and there are strong linkages of SV with Cw2 and Bw with Cw3. The possible presence of further variants at the A- and B-loci is reported. The proportion of B-locus antigen “blanks” in this study is 5.9%. Relationships have been sought between the HLA antigens and diseases studied: the antigen A29, possibly in linkage with Bw42, shows a correlation with disease susceptibility, and associations are suggested between Bw44 (in possible combination with Aw36) and resistance to both BL and NPC, and between Bw45 and long-term remission in NPC.  相似文献   
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