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1.
T淋巴细胞表面的TRBC受体不同介导E花结形成的E受体(CD2)和E2分子。CD2的配体,人红细胞表面的CD58(LFA-3)和绵羊红细胞表面的T11 TS,S42,S14及S110-220,与TRBC受体的配体无关,TRBC玫瑰花结的形成是通过不同于E花结和人自身玫瑰花结的受体-配体相互作用来实现的,进一步表明,人和猴T淋巴细胞表面和TRBC表面,可能都有独特的蛋白质分子介导TRBC玫瑰花结的形成。  相似文献   

2.
TRBC受体不同于已知的全T细胞表面分化抗原CD2,CD3/TCR复合物,CD5,CD6和CD7。CD2分子不参与TRBC玫瑰花结的形成,也不是介导E花结的唯一分子。至少有两个或两个以上蛋白质与TRBC玫瑰花结和E花结的形成有关,其中有的分子为E受体和TRBC受体所共有。因此,很可能有不同于CD2的分子参与了TRBC玫瑰花结的形成。  相似文献   

3.
树免疫细胞体外感染Ⅰ型人免疫缺陷病毒的实验研究   总被引:1,自引:1,他引:0  
至今可以感染Ⅰ型人免疫缺陷病毒(HIV-1)的动物只有黑猩猩和长臂猿,这严重阻碍了HIV-1的疫苗研究和治疗研究。因此,寻找新的可以感染HIV-1的动物模型成为十分迫切的课题。已知树鼩对许多重要的医学病毒易感,为了探讨树鼩是否可以感染HIV-1,利用不同辅助受体的5种HIV-1病毒株,体外感染云南野生成年树鼩的淋巴细胞和单核/巨噬细胞;同时还用这些病毒感染人外周血淋巴细胞或单核细胞。然后用RT-PCR、PCR和流式细胞术分别进行检测。用RT-PCR方法未检测到感染上清中有病毒粒子的存在,用PCR法未能发现树鼩的这些免疫细胞中有前病毒DNA,用流式细胞术也未能在这些感染HIV-1的树鼩细胞的表面检测到特异抗原;而感染HIV-1的人免疫细胞均为阳性结果。实验结果表明树鼩的这些免疫细胞在体外未能感染上HIV-1,可能的原因是树鼩的这些免疫细胞的HIV-1受体(CD4)和辅助受体(CCR5或CXCR4)与人的免疫细胞差别较大。  相似文献   

4.
本文研究了豚鼠E花环形成狗淋巴细胞(E-RFC)的类别。狗淋巴细胞于37℃孵育后,可提高E花环形成率。E-RFC与总淋巴细胞的SIg阳性率相近。E-EAC(豚鼠红细胞—抗体和补体包被的绵羊红细胞)混合花环实验表明一部分狗淋巴细胞同时具有E和补体二种受体,总淋巴细胞与补体受体淋巴细胞的E花环阳性率无显著差异。这些结果说明E受体不仅表现于一部分T细胞上,而且见于某些B细胞上。因此,不宜用E花环试验作为检测狗T细胞的方法。  相似文献   

5.
用经过氨乙基异硫脲(AET)或神经氨酸酶(VCN)处理过的绵羊红细胞(SRBC),酵母多糖—补体复合物(ZYC)和红面猴红细胞(SMRBC)作为标记,测定了健康恒河猴、熊猴、豚尾猴、红面猴和树鼩的外周血以及恒河猴淋巴样组织的淋巴细胞亚群,在这五种动物中,E_(AET)玫瑰花结形成细胞的百分比依次为78.1±6.4,77.7±4.2,76.0±6.4,82和24.9±7.2。ZYC形成细胞的百分比依次为11.4±4.2,9.0±3.8,12.8±2.2,15和15.7±7.4。恒河猴胸腺,脾脏和淋巴结的E_(AET)形成细胞的百分比分别为95.2±2.9,28.8±10.3,44.8±6.2。与人类不同,SMRBC不是恒河猴B淋巴细胞的标记。此外,还与其他作者的结果进行了比较。  相似文献   

6.
本文建立了一种较稳定、理想的人淋巴细胞体外诱导绵羊红细胞(SRBC)特异性抗体生成的系统。用SRBC体外刺激人扁桃体淋巴细胞,用溶血空斑法计数针对SRBC特异性抗体形成细胞。发现极低量抗原可诱导其抗体形成,抗体形成量随抗原量呈规律性变化;在抗原刺激后的第4天特异性抗体开始出现,第6天达高峰,并稳定维持至第8天;在辅助刺激剂美洲商陆(PWM)存在下,抗体形成量显著高于无PWM的情况;除去人扁桃体细胞中粘附细胞(主要是巨噬细胞)才能诱导最适抗体形成。将具感染性的HSV-1与SRBC一起加入淋巴细胞培养中,可显著抑制SRBC诱导的特异性抗体形成,这一抑制效应与病毒的感染量有关。此系统中同时加入α-干扰素则可部分解除病毒的抑制效应,并且解除效果与α-干扰素的剂量有关。  相似文献   

7.
淋巴细胞在有丝分裂原或特异性抗原刺激下,部分淋巴细胞周围吸附多层羊红细胞,称为巨大E-花环(Giant SRBC rosette,E_G花环)。关于E_G花环的形成已屡见不鲜,但对其形成机理的探讨尚付缺如。我们用SRBC受体和SRBC的凝集反应证实了SRBC和SRBC间的结合是通过受体分子连接起来的。并推测受体分子和SRBC的结合价为两价或两价以上而和人T细胞的结合价则为一价。提取的游离受体使RRBC凝集的原因可能是暴露了受体在T细胞表面时被隐蔽的部位,这些部位提供了与RRBC结合的机会。当然也不能排除在SRBC受体的制备中还存在着与RRBC结合的组分。  相似文献   

8.
淋巴细胞在有丝分裂原或特异性抗原刺激下,部分淋巴细胞周围吸附多层羊红细胞,称为巨大E-花环(Giant SRBC rosette,E_G 花环)。关于E_G 花环的形成已屡见不鲜,但对其形成机理的探讨尚付缺如。我们用SRBC 受体和SRBC 的凝集反应证实了SRBC 和SRBC 间的结合是通过受体分子连接起来的。并推测受体分子和SRBC 的结合价为两价或两价以上而和人T 细胞的结合价则为一价。提取的游离受体使RRBC 凝集的原因可能是暴露了受体在T 细胞表面时被隐蔽的部位,这些部位提供了与RRBC 结合的机会。当然也不能排除在SRBC 受体的制备中还存在着与RRBC 结合的组分。  相似文献   

9.
黄玲  徐叔云 《生理学报》1990,42(5):469-475
本文利用实验性“甲高”和“甲低”小鼠模型,观察了甲状腺素(L-T4)对绵羊红细胞(SRBC)诱导小鼠脾细胞产生 IgM 的影响。并采用放射配体结合法,测定了不同甲状腺机能状态的小鼠在免疫反应过程中,脾淋巴细胞上 β-肾上腺素能受体(β-Adr.R.)的密度及亲和力的变化。结果发现,用 SRBC 免疫后第3—5天,甲高小鼠脾细胞产生的 IgM 及脾淋巴细胞上β-Adr.R.密度的增加均明显高于对照小鼠(P<0.01),甲低小鼠则相反,其 IgM 的生成及脾淋巴细胞上β-Adr.R.密度的增加均明显低于对照小鼠(P<0.01),受体亲和力不随小鼠甲状腺机能状态及免疫状态的改变而改变(P>0.05)。以上结果提示,L-T_4能促进小鼠对SRBC 的免疫反应,其机制可能与淋巴细胞上 β-Adr.R.的密度变化有关。  相似文献   

10.
为应用猕猴和树鼩动物模型研究毒品成瘾对神经/免疫系统的影响提供基础数据,对大麻素及阿片受体在正常猕猴和树鼩神经系统和免疫系统的表达进行初步确定.采集正常猕猴和树鼩新鲜组织(皮质、小脑、脑干、海马、脊髓、脾脏),应用半定量逆转录PCR和实时定量PCR的方法检测大麻素与阿片受体mRNA在猕猴和树鼩各组织中的表达情况.猕猴脑部各区包括脾脏均表达大麻索受体1(CNR1),而大麻素受体2(CNR2)只表达于脾脏内.三类阿片受体中,mu(μ)受体表达最为广泛,在以上各组织中均有表达;delta(δ)受体表达的组织最少,只在海马表达;kappa(κ)受体表达介于两者之间,分别在皮质、小脑、脑干、脊髓中表达.在树鼩组织中,CNR1和CNR2表达于整个大脑重要脑区中,且CNR1表达量高于同一区域内CNR2表达的鼍:脾脏中CNR2的表达较高,而CNR1不表达.三类阿片受体只有检测到μ受体在脑部与脾脏表达,且在各个脑区的表达量明显高于脾脏的表达量;δ体和κ受体在被检各个组织中均无表达.总体而言,两种大麻素受体在猕猴和树鼩体内表达情况与人类和鼠的情况类似,而三类阿片受体在猕猴体内表达情况与人类吏为接近.猕猴和树鼩可能可用于人类毒品成瘾的研究;猕猴在某些神经受体的表达更接近人类,其在研究毒品成瘾的机理和对免疫系统的影响方面仍有不可替代的地位.  相似文献   

11.
人和猴T淋巴细胞表面TRBC受体和E受体的比例研究   总被引:2,自引:1,他引:1  
In 1985, rosette formation of human and macaque pan-T lymphocytes with tree shrew red blood cells (TRBC) (TRBC rosette) was first found by Ben K et al, showing different physico-chemical properties from that of rosette formation with sheep red blood cells (E-rosette). In order to approach the correlation between TRBC receptor, E receptor (CD2) and other differentiation antigens (CDs) on T lymphocytes, rosette inhibition assay and antigenic modulation or co-modulation were performed with monoclonal antibodies (McAbs) to CDs, and the distribution of TRBC receptor in other peripheral immunocytes, cell lines was also examined. TRBC rosette appeared in 88.8% of E rosette positive peripheral blood lymphocytes (E(+)-PBL) and in 4.16% of E(-)-PBL. TRBC receptor was also found on all T cell lines tested (CEM, H33 HJ-JA 1, Jurkat, MLA-144, Molt-3, Molt-4, Molt-4 clone 8, PEER) and some myeloid lines (U 937 and HL 60), but not on human granulocytes, B cell lines (Daudi, Raji and Reh) and myeloid line K 562. The modulation or co-modulation of CD 3, TCR, CD 5, CD 6 and CD 7 with McAbs OKT 3, T 108 (F 1), T 136 (F 101-15), T 149 (M-T 604) and T 152 (7 G 5) did not affect TRBC rosette formation of PBL. TRBC rosette of human and rhesus monkey PBL was not inhibited by T 11.1 McAb OKT 11 (CD 2 McAb), in contrast human and rhesus monkey E rosette formations were obviously blocked at inhibition rates of 77.9% and 49.3%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

12.
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   

13.
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   

14.
A new method of detecting the C3b receptor is reported. A particular merit of this method is that anti-RBC rabbit antiserum is not required. Rosettes were formed with human B lymphocytes, B lymphoblasts and granulocytes, using sheep erythrocytes (SRBC) sensitized with fresh human serum (FHS). T lymphocytes and T lymphoblasts did not form rosettes. The percentage of cells forming rosettes with this method approximated the percentage of rosettes formed with EACm. However, FHS coated SRBC did not react with most cells of B cell type chronic lymphocytic leukemia (CLL), whereas EACm rosette formations showed a definite reaction. On the other hand, 34--58% of cells of chronic myelocytic leukemia (CML) bound with the indicator red cells. SRBC sensitized with fresh rabbit or guinea pig serum formed rosettes with PBL, tonsil cells, B lymphoblasts and granulocytes. Complement and IgM antibody were required for this reaction, as in EAC rosette formation.  相似文献   

15.
Sheep erythrocytes (E) were treated with papain or neuraminidase to evaluate what effect these enzymes would have on the E rosette test for human T lymphocytes. Few or no rosettes were detected with sheep erythrocytes treated with papain (EP). Sensitization of EP with rabbit antibody and mouse complement resulted in a rosette indicator (EPAC) which could be used to detect peripheral blood complement receptor lymphocytes (CRL) and thymocyte CRL without having to perform the rosette assay at 37 °C. Neuraminidase treatment of E (EN) enabled the detection of approximately 20% more rosette-forming cells (RFC) in human peripheral blood lymphocyte (PBL) suspensions compared to untreated E. Rosette studies on a patient with severe combined immunodeficiency disease and on human lymphoblastoid cell lines showed that the additional rosettes detected with EN were T lymphocytes.  相似文献   

16.
Peripheral blood lymphocytes from healthy humans formed stable E rosettes with sheep erythrocytes (SRBC) at 37°C after culture with phytohemagglutinin or the divalent cation ionophore A23187. Cells manifesting this phenomenon exhibited “blast” morphology, appeared by 16 hr of culture, increased dramatically in percentage and absolute number by 62 hr, and persisted in large numbers for the duration of culture (182 hr). Unstimulated lymphocytes formed rosettes at 4°C but not at 37°C. Increased “stickiness” due to surface-bound lectin mitogen was not the cause of rosette formation at 37°C.Formation of E rosettes at 37°C has previously been considered a property of lymphocytes less differentiated than the circulating T cell (e.g., thymocytes, leukemic lymphoblasts). The present findings indicate that this property can be “reexpressed” during blastogenesis in culture.This observation also demonstrates technical problems associated with the use of SRBC to quantitate lymphocytes with complement receptors (B cells) by the EAC rosette assay in culture. False positives resulted from 37°C E rosette formation, but this was overcome by replacing the SRBC with guinea pig erythrocytes in the EAC assay.  相似文献   

17.
Cat thymocytes, bone marrow cells, and peripheral blood leukocytes (PBL) formed rosettes with guinea pig (GP) and gerbil (G) erythrocytes (E). In PBL from adult cats the frequency of rosettes was 27% with GPE and GE, while an average of 33% bone marrow cells formed rosettes with GPE and only 4% with GE. Thymocytes from kittens showed a high percentage of rosettes with both GPE and GE (35 to 81%), with the frequency of each type varying with the thymus tested. Fluorescein isothiocyanate labeling of one of the erythrocyte species revealed these cells to be rosetting with different nucleated cells; i.e., a low percentage (3-5%) of the rosettes formed with PBL and bone marrow had both labeled and unlabeled erythrocytes. In contrast, "mixed" rosettes were observed with a significant number of thymocytes, averaging 33% of thymocytes from six animals. A further distinction between the GE- and GPE-rosetting cells was revealed by a monoclonal antibody which blocked GE rosette formation without interfering with the binding of GPE to PBL and thymocytes. PBL could be depleted of either GPE- or GE-rosetting cells, with retention of IgG+ cells and cells capable of rosetting with the second erythrocyte species in the nonrosetting fractions. Stimulation of the latter nonrosetting fractions with pokeweed mitogen for induction of Ig synthesis revealed a T-lymphocyte specificity of the GE- and GPE-rosetting cells. PBL depleted of GE-rosetting cells yielded an increased Ig production, two- to threefold above the control; in contrast, depletion of GPE-rosetting cells from PBL resulted in a failure of the remaining cells to respond. These results suggest that T-suppressor cells of the cat are contained in the GE-rosetting fraction and T-helper cells are rosetted with GPE.  相似文献   

18.
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   

19.
Rosette formation by human thymocytes   总被引:6,自引:0,他引:6  
A proportion of lymphocytes in human fetal and post-natal thymus, and in blood, formed rosettes with red blood cells from sheep and pig. The count of rosette-forming cells (RFC) among human thymocytes varied widely, from 2–216 per thousand cells, and was higher in fetal than in post-natal life. The count of RFC among human thymocytes was not reduced by specific rabbit anti-human immunoglobulin sera, indicating that the receptor was not of immunoglobulin character; the reaction was inhibited by antithymocyte serum and metabolic poisons and certain enzymes. The receptor may be equivalent to other “non-specific” glycoprotein hemagglutinins in plants and viruses.The importance of species differences in immunological assays is emphasized. Thus human thymocytes gave high counts of RFC only with red blood cells of sheep and pig; moreover thymus lymphocytes from only man and pig, but not several other species including rodents, were highly reactive with sheep red blood cells. The capacity for rosette formation could be a marker for T cells in human blood.  相似文献   

20.
Human T cells spontaneously bind sheep E and this reflects physiologic interactions between specific adhesion molecules, principally T cell CD2, and the sheep equivalent of LFA-3. This interaction is important in T cell adhesion and in transmission of accessory activational signals. In this respect, E rosettes provide a partial analogue for T cell:accessory cell interaction and rosetting induces functional alterations in T cells. In studies of Ag-dependent T cell activation, we have obtained evidence that the formation of covalent Schiff bases between ligands on APC and T cell is an essential element. In our study, the specific chemical criteria defining Schiff base formation were applied to T cell E rosettes formed at room temperature, as follows: 1) Prior formation of Schiff bases on T cell epsilon-amino groups by glutaraldehyde inhibited E rosette formation. 2) Rosette formation was inhibited in the presence of exogenous lysine. 3) Reduction of constitutive T cell aldehydes by NaBH4 inhibited subsequent E rosette formation. In response to these chemical modifications of cellular ligands, T cell E rosette formation and T cell inductive interaction with APC were affected in the same way. 4) Oxidation of NaBH4-treated T cells by NaIO4 or galactose oxidase to regenerate cell-surface aldehydes on N-acetylneuraminic acid or galactose residues respectively, consistently restored E rosette formation. 5) Conversion of reversible Schiff bases to irreversible secondary amines by NaCNBH3 stabilized E rosettes against mechanical disruption. Together, these data demonstrate that E rosettes provide an analogue for the Schiff base-forming reactions that are essential in specific T cell activation.  相似文献   

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