首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
参与人自体花结(A花结)形成的分子(如CD2/LFA-3),与免疫细胞的粘附和激活有关。我们曾发现,人和猴淋巴细胞表面的树鼩红细胞(TRBC)受体不同于绵羊红细胞(SRBC)受体(CD2),可能是一种新的白细胞分化抗原。花结试验表明,树鼩的外周血淋巴细胞(TPBL)和胸腺细胞都能形成A花结,结花率分别为20.9%和11.1%;而绵羊红细胞花结(E花结)形成率分别是20.9%和1.1%。以四种单克隆抗体(McAb)(Leu 5,0-275,AICD2.1和E2 McAb)进行树鼩A花结和E花结的抑制与抗原调变试验,结果表明,这些抗体对树鼩的A花结都没有明显的抑制或调变作用,但对E花结的抑制及调变作用明显。说明TPBL表面的TRBC受体不同于SRBC受体,与CD2/LFA-3及E2分子无关。因此,TPBL的A花结与E花结形成机制不同。  相似文献   

2.
Phenomenon of the lymphocyte interaction with autologous erythrocytes was revealed in the patients with auto-immune diseases. Macroscopically this phenomenon appeared in the form of hemagglutination, and microscopically--of "rosette" formation. No lymphocyte interaction with autologous erythrocytes was found in the group of normal subjects and patients without autoimmune disorders.  相似文献   

3.
A minority (1–2%) of normal mouse lymphoid cells bind autologous erythrocytes and form rosettes. In this study we examined the antigenic specificity involved in the formation of such rosettes. A significant difference in the incidence of rosettes formed, respectively, with autologous and allogeneic mouse erythrocytes is found. Moreover, preincubation of lymphoid cells with low concentrations of syngeneic erythrocytic ghosts causes significant competitive inhibition of subsequent rosette formation. Allogeneic ghosts obtained from nonrelated or from congenic resistant strains of mice do not display this inhibitory effect under the same conditions. It is thus suggested that mouse autologous rosette-forming cells bear receptors for syngeneic H-2 antigens that are involved in the binding of autologous erythrocytes. More precisely, compatibility between lymphocyte and erythrocyte restricted to K or D only is sufficient to ensure a level of rosettes similar to that obtained when complete identity occurs for K, I, and D regions.  相似文献   

4.
As part of an investigation of mononuclear phagocytes in malignant lymphoma, measurement of immune-mediated erythrophagocytosis and rosette formation was carried out on cells grown in suspension culture at the monocyte (Day 0) and macrophage (Day 6) stages; the culture medium contained autologous serum. Cells were derived from 10 patients with untreated non-Hodgkin's lymphoma (NHL) and from 12 normal individuals. The results were subjected to Analysis of Variance and demonstrated a significant difference between the two groups with respect to erythrophagocytosis but not to rosette formation. In the NHL group, the proportion of erythrophagocytic cells showed no significant increase between the monocyte and macrophage stages (0.07 to 0.09), in contrast to the marked increase seen in the normal group (0.09 to 0.24). In a pilot investigation to examine the possible role of factors in the serum, cells derived from the NHL patients were cultured with serum from healthy donors; they showed no significant difference in the immune-mediated functions from those grown in autologous serum. Overall, the results provide further quantitative evidence of defective macrophage maturation in NHL, presumably reflecting the compromise of host defence mechanisms.  相似文献   

5.
The interaction of extravascular erythrocytes with lymphocytes, macrophages, polymorphonuclear leucocytes and fibroblast like cells in human gastric ulcer and in post-ulcer scar was studied by means of electron microscopy and cytochemical methods. It was shown that such interaction results in autologous rosette formation. There were also autorosette in the capillaries where autorosette forming cells were endothelial cells and lymphocytes. Many kinds of autorosette forming cells were connected with some peculiarities of ulcer process in the stomach.  相似文献   

6.
Three T cell markers (heterologous sheep rosette, autologous rosette, and theta antigen) have been studied in thymocytes after in vivo injection of a single dose of serum thymic factor (Facteur Thymique Sérique: FTS). Within 24 h after such treatment, sheep erythrocyte-binding cells increased 5 to 8 times, while autologous rosette-forming cells decreased by a factor of 3. Using cytotoxicity assays (trypan blue exclusion test and chromium release) it was observed that thymocytes from FTS-treated mice presented a higher sensitivity to antitheta serum and complement than control mice. These results are compatible with the hypothesis that exposure of immature T cells to thymic hormone may induce T cell maturation, as assessed by decreased number of immature autologous rosette forming cells (RFC) and increased number of mature T cells (sheep RFC and theta-positive cells). Facteur Thymique Sérique appears as an interesting probe to define the various intra-thymic cellular compartments of differentiation.  相似文献   

7.
The incubation ratio of sheep red blood cells (SRBC) to lymphocytes is a critical factor in rosette formation, whereas the length of time SRBC and lymphocytes are incubated together does not significantly affect the percentage of lymphocytes forming rosettes. The graph obtained by plotting percentage of rosette formation against the ratio of SRBC to lymphocytes is similar to that resulting from the formation of bimolecular complexes. If rosette formation is analogous to formation of bimolecular complexes, maximal rosette formation occurs when the system is saturated, i.e., with excess SRBC, and is a measure of the total capacity of a lymphocyte population to form rosettes. In addition, the percentage of rosette formation observed at a limiting SRBC/lymphocyte ratio gives an indication of the avidity of the lymphocytes for SRBC. This interpretation may provide an explanation for the difference between the "active" and "total" rosettes. When the log of the SRBC/lymphocyte ratio is plotted against percentage of rosette formation, a straight line is obtained, suggesting that within a given normal lymphocyte sample, T cell subsets with different avidities are not detected by rosette formation at different SRBC/lymphocyte ratios.  相似文献   

8.
Human lymphocytes from different lymphoid organs were examined for rosette formation with autologous erythrocytes. The autorosette-forming cells (A-RFC) were shown to belong to a T cell subset including less mature lymphocytes. When normal human peripheral blood lymphocytes were stimulated with low doses of the plant lectin concanavalin A (Con A), in the presence of autologous plasma, the A-RFC levels were strongly enhanced. This response gave rise to two peaks: the first one coincided with the peak of thymidine incorporation but the maximum increase occurred 5 or 6 days later when the proliferative response was impaired. Depletion of A-RFC before stimulation with Con A led to a clear-cut decrease in autorosette levels at both peaks of the response. It is concluded that Con A, generally used for polyclonal activation against heteroantigens, may also result, in terms of A-RFC marker, in expansion of an autoreactive T cell population.  相似文献   

9.
We found that the formation of multilayer rosettes by transformed human blood lymphocytes after phytohemagglutinin (PHA) stimulation is correlated with conformational changes of the chromatin as seen by premature chromosome condensation (PCC). The frequency distribution of grades of PCC and multilayer rosette formation suggests that changes in chromatin are a prerequisite for rosette formation. Rosette formation was most pronounced for 24-h and 48-h cultures. Chromatin decondensation and rosette formation showed identical patterns. The possibility that multilayer rosette formation is directly dependent on conformational changes of chromatin is discussed.  相似文献   

10.
Spontaneous rosette formation in humans is restricted to a subpopulation of the circulating T cells. We have previously shown that the interaction between lymphocytes and autologous red blood cells (auto-RBC) is not mediated by a self-recognition mechanism, since allogeneic (allo-) RBC bind to T cells through the same receptors. In this work, we have extended these observations to thymocytes. Using a mixed-rosette assay in which one type of erythrocyte was identified by FITC labeling, we have shown that almost all the thymocytes which attached auto-RBC could also fix allo-RBC. However, as for the peripheral blood lymphocytes (PBL), binding of human RBC to thymocytes occurred with varying affinities according to the erythrocyte's origin. In order to further study the specificity of the erythrocyte to lymphocyte binding in rosette formation, PBL were mixed with auto-RBC and erythrocytes of xenogeneic (xeno-) origin. Although very disparate incidences of rosettes were found according to the species from which the RBC were derived, most of the autorosetting lymphocytes also had receptors for xeno-RBC. In addition, preincubation of PBL with monoclonal antibody OKT11A (directed against the sheep RBC receptors on T cells) completely abrogated rosette formation with all the erythrocytes tested (human auto- and allo-, sheep, pig, and rabbit) except mouse RBC. Taken together these data strongly suggest that human auto- or allo-, as well as sheep or some other xeno-RBC, bind to T lymphocytes by a single receptor and that the combining sites are expressed with different densities or varying affinities depending upon the RBC's origin. Therefore, spontaneous autorosettes may represent T lymphocytes having high-affinity receptors for sheep RBC.  相似文献   

11.
Increasing evidence indicates that rosettes which spontaneously from between human T cells and E might be of physiologic relevance. We show here that another T cell-surface molecule than CD2 is involved in rosette formation. Four mAb have been obtained reacting with human T cells that block rosettes with E from many species, including autologous cells. They react with a molecule, we termed E2, which is actively synthetized by T and monocytic cells. Immunoprecipitation revealed a major 32-kDa band. Immunoblots revealed a major 32-kDa band and a minor 20-kDa band. This molecule was detected on all T cells tested--and present at high densities on corticothymocytes, but at low densities on medullary thymocytes. It was also found on monocytes but not on B cells. However B-CLL cells did carry this molecule. E2 molecules were also detected on nonhematologic cells. Together with the recent evidence that 3 molecules from the erythrocyte surface are also involved for rosettes, intricate molecular interactions would account for adhesion of T cells to autologous E and possibly autologous nucleated cells.  相似文献   

12.
In connection with our discovery of a strong immunosuppressive activity of cyclolinopeptide A (CLA), we investigated immunosuppressive properties of antamanide and a number of its analogues, including symmetrical antamanide, and compared them with the activities of cyclosporin A and CLA. The peptides were investigated by using plaque forming cell (PFC), graft-versus-host (GvH), delayed type hypersensitivity (DTH), and autologous rosette formation cell (ARFC) tests. Antamanide and symmetrical antamanide exhibit an immunosuppressive activity lower than CLA. Linear antamanide fragments are also active. At higher concentrations of the latter peptides, toxic effects occur.  相似文献   

13.
CD2 (E receptor, LFA-3 receptor) and E2 molecules (Bernard, 1988) on human T lymphocytes, CD58 (LFA-3, lymphocyte function associated antigen 3) on human erythrocytes and S14,S42,S110-220 molecules (Bernard, 1987) of sheep erythrocytes are involved in rosette formation of human T lymphocytes with human or sheep erythrocytes. Rosette formation of human and macaque pan-T lymphocytes with tree shrew (Tupaia belangeri) red blood cells (TRBC) (TRBC rosette) has shown different physicochemical properties from that of rosette formation with sheep red blood cells (E rosette) (Ben, 1985). CD2, CD3/TCR complex, CD5, CD6, and CD7 are not involved in TRBC rosette formation (Zheng, 1990). In order to know whether E2, LFA-3,S14,S42 and S110-220 molecules are involved in TRBC rosette formation or human and macaque T lymphocytes, rosette inhibition and antigenic modulation or co-modulation were performed with relevant monoclonal antibodies (McAbs), and hemolytic assay and slide agglutination were also conducted. TRBC rosette formation of human and rhesus monkey PBL was not blocked by E2 McAb (inhibition rate 2.8% and 2.1%, respectively). In contrast, human E rosette formation was obviously blocked at inhibition rate of 49.8% and macaque E rosette formation was slightly inhibited (13.3%). The modulation or co-modulation of E2 molecule with E2 McAb did not affect human TRBC rosette formation. Similar results were shown in rosette formation inhibition of Jurkat cells.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

14.
The effect of ferric citrate on active E, EA, and EAC rosette formation by human peripheral blood mononuclear (PBM) cells was examined. Active E and EAC rosette formation was significantly inhibited at four of the five concentrations tested. Inhibition of EAC rosette formation was generally lower than that observed with active E rosette formation. Treatment with Fe3+ had no effect on EA rosette-forming cells.  相似文献   

15.
Concanavalin A (Con A) induces rosette formation of erythrocytes around polymorphonuclear leucocytes and lymphocytes in cell suspensions of autologous human blood cells. The effect which is most characteristic in a concentration between 25 and 50 microgram/ml is due to Con A bound on the erythrocyte membrane. A similar effect, although less pronounced, was observed with phytohaemagglutinin at concentrations of 10 and 25 microgram/ml. The treated erythrocytes showed a higher affinity to polymorphonuclears when compared with lymphocytes. At the contact area, the membrane of the erythrocyte became highly folded while its free surface was smooth and spherical. The effect of the local concentration and immunobilization of the lectin on the erythrocyte membrane and the similarity of the contact pattern to that of erythrophagocytosis are discussed.  相似文献   

16.
Self-recognition assessed by rosette formation by lymphocytes with erythrocytes of syngeneic or autologous origin is a very primitive function that is present before lymphoid system development proper in the thymus. Autologous rosette-forming cells (A-RFC) have been found in the very early yolk sac of pregnant mice of 10–11 days gestation. Moreover, when these 10- to 11-days' gestation pregnant mice were subcutaneously injected with facteur thymique sérique (FTS) 1 day before A-RFC examination, it appears that FTS reduces the number of A-RFC in the yolk sac by 63%. Thus it has not been possible to determine whether FTS acted by changing the migration capacity or the expression of receptors on the cell surface.  相似文献   

17.
A rosette-type assay of the physical interaction between lymphocytes and monocytes after treatment with neuraminidase-galactose oxidase (NGAO) is reported. Monocyte-lymphocyte (ML) rosette formation and subsequent lymphocyte proliferation occurred when either lymphocytes or homologous monocytes were treated with NGAO and cultured together. Maximal ML rosette formation took place at 37 degrees C 4 hr after culture in media containing 10% serum at lymphocyte to monocyte ratios of 10:1 to 20:1. The percentage of rosette formation correlated with the extent of thymidine incorporation when increasing concentrations of NGAO were used. When NGAO-treated monocytes were added to untreated T and non-T lymphocytes, they bound preferentially to T lymphocytes and induced proliferation only in the T subpopulation. These results indicate that the ML rosette assay measures a highly specific monocyte-lymphocyte physical interaction after a mitogenic stimulus which is an early event in lymphocyte activation since it reflects the degree of subsequent lymphocyte proliferation.  相似文献   

18.
Adherent cells in human peripheral blood mononuclear cells were removed by the attachment to the plastic surface of tissue culture dishes. After removal of adherent cells, early rosette-forming cells (early RFC), which were characterized by early (5 min) rosette formation with sheep blood cells (SRBC) at an SRBC to lymphocyte ratio of 8:1, were separated from nonrosetting cells by sedimentation on Ficoll-Hypaque gradient. Total (60 min) rosette formation was carried out with the early RFC-depleted cell population on the gradient interface by the use of neuraminidase-treated SRBC at an SRBC to lymphocyte ratio of 20:1 and the resulting rosette-forming cells (late RFC) were sedimented by gradient centrifugation. These T cell subpopulations, early RFC-enriched and late RFC-enriched, were reasonably pure with respect to the ability to bind SRBC and contained less than 0.5% monocytes. Monocyte preparations, which were obtained after vigorous washing of the adherent cell layers on tissue culture dishes, responded to phytohemagglutinin P (PHA-P) or concanavalin A (Con A) with negligible incorporation of 3H-thymidine. There was no significance difference in the responsiveness to PHA-P between early RFC-enriched and late RFC-enriched populations either in the absence or in the presence of graded numbers of additional autologous monocytes. However, the response of early RFC-enriched population to Con A was significantly poor as compared with that of late RFC-enriched one unless additional monocytes were added. In the presence of 20% autologous monocytes in the culture, the Con A-induced response of early RFC-enriched population was markedly enhanced to reach close to that of late RFC-enriched population. These results suggest that early RFC and late RFC might be different from each other in their responsiveness and in their need for monocytes on the stimulation with Con A.  相似文献   

19.
Mouse thymocytes and erythrocytes form rosettes when incubated together at 4 degrees C. The frequency is much higher when the thymocytes and erythrocytes are MHC-identical. If the indolizidine alkaloid swainsonine (SW) is present during rosette formation at concentrations of 1 microgram/ml (5.7 microM) or greater, rosette formation between MHC-identical pairs is inhibited to levels comparable to those observed for MHC-different pairs; rosette formation by MHC-different pairs is not affected. This was confirmed by examining 17 different MHC-identical combinations (9 completely syngeneic and 8 differing in non-MHC genes) and 13 MHC-different combinations (3 of these identical everywhere except at MHC). A SW-inhibitable component of rosette formation was observed only when thymocyte and erythrocyte were completely identical at MHC. Thus F1-parent pairs behaved as if allogeneic, although both F1-F1 and parent-parent had a SW-inhibitable rosetting component. Similarly, inbred strains only partially MHC-identical (B10.BR-B10.A, B10.D2-B10.A) behaved as if allogeneic. The SW-inhibitable component of rosetting could be partially but significantly blocked by including monoclonal antibodies against Thy-1, and anti-CD4 plus anti-CD8 (together but not separately); anti-class-I-MHC produced some inhibition of marginal significance. Monoclonal antibodies against class-I-MHC, LFA-1, and CD3 did not block. Pretreatment of erythrocytes with neuraminidase, greatly reduced the SW-inhibitable component of rosetting. The SW effect would appear to be due to a direct interaction of SW with a cell surface structure involved in syngeneic rosette formation rather than the known ability of SW to block the processing of N-linked sugar structures. The results are consistent with cell surface lectins and cell surface sugars playing a role in rosette formation.  相似文献   

20.
A distinction between B-CLL and other malignant B-cell lymphomas in the leukaemic phase may be difficult. Mouse red blood cell rosette formation of lymphocytes from 97 patients with B-CLL and 19 patients suffering from other B-cell lymphoproliferative disorders was examined together with lymphocyte rosette formation of healthy controls. The majority of circulating lymphocytes of B-CLL patients formed rosettes with mouse red cells, whereas there was no relationship between the number of peripheral neoplastic B-cells and that of rosette forming cells in other lymphoproliferative diseases. The relatively simple mouse red blood cell rosette assay proved to be of value in the differentiation of otherwise nearly related conditions.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号