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1.
Abstract

Marijuana, and specifically its psychoactive component, THC, can up or down regulate lymphocyte proliferation in murine spleen cells depending in part on the method used to stimulate the cells. This study identifies a difference in THC induced disregulation using cells derived from two different secondary lymphoid organs, the spleen and the lymph node. It was found that THC treatment of mitogen (concanavalin A or phytohemagglutinin) stimulated cells derived from either organ resulted in suppression of the proliferative response. In contrast, spleen cells stimulated with anti-CD3 antibody and treated with low doses of THC displayed an enhanced proliferation whereas the response in lymph nodes did not change. The cell type involved with this THC immunoenhancement in spleen cells was found to be the Ly2 cell. Further differences in the THC modulation of Ly2 spleen cells as compared to lymph node cells were noted following stimulation with PHA. Proliferation of Ly2 cells of splenic origin was inhibited with low doses of THC whereas the Ly2 cells of lymph node origin were more resistant to this drug induced suppression. This study, therefore, demonstrates differences in the immunomodulatory capability of THC dependent upon the organ source of the lymphocytes.  相似文献   

2.
Using monoclonal anti-trinitrophenyl (TNP) antibodies complexed to TNP-myoglobin-coated gold particles, we analysed at the ultrastructural level the retention by follicular dendritic cells (FDC) of immune complexes containing various antibody isotypes. Gold-labelled immune complexes were injected subcutaneously or intravenously into naive mice and, after 24 h, germinal centres of draining lymph nodes or spleen were examined by electron microscopy. FDC generally retained complexes containing IgG2a and IgG2b better than those formed with IgG1 or IgG3. IgM was rarely retained. FDC isolated from lymph nodes or spleens were incubated in vitro with gold-labelled complexes in a serum-free medium. IgG2a and IgG2b complexes were also retained in vitro in large quantities by FDC; IgG1 and IgG3 complexes were retained in smaller quantities or in highly variable quantities compared with IgG2; IgM complexes were rarely seen on FDC. There was no difference between FDC isolated from lymph nodes or from spleen with respect to the Ig isotypes required for Fc-mediated retention of immune complexes.  相似文献   

3.
Five imidazole compounds were added to cultures of human lymphocytes which had been stimulated to undergo blast transformation by exposure to phytohaemagglutinin, poke-weed mitogen or allogeneic cells. Two compounds, clotrimazole and dacarbazine (DTIC) produced a dose related suppression of these responses. Nirnorazole was largely inactive whereas metronidazole and tinidazole actually enhanced the response -at least in those cultures stimulated by the plant mitogens. It is suggested that experiments of this kind are helpful in identifying those imidazole compounds that could be used as immunosuppressants in vivo.  相似文献   

4.
C57BL/6 mice were immunized intravenously (i.v.), intraperitoneally (i.p.), or subcutaneously with one dose of Bacillus Calmette-Guérin (BCG). At various time intervals after injection, the lymphocyte response, as measured by thymidine incorporation into DNA, and the number of immunoglobulin-secreting cells were determined in vitro before and after mitogenic stimulation with phytohemagglutinin, concanavalin A, or lipopolysaccharide. In unstimulated cultures, the spontaneous thymidine incorporation and immunoglobulin synthesis of spleen cells were increased to some extent in mice infected i.p. or i.v. with BCG, as compared with noninfected mice. In contrast, after mitogenic stimulation, a marked depression of the proliferative response of spleen cells to both T- and B-cell mitogens and a marked inhibition of LPS-induced immunoglobulin secretion were observed in mice infected i.v. and to a lesser extent in those infected i.p. The depression of lymphoblastogenesis in spleens was fully established 15 days after infection and persisted for a long period of time. When unfractionated or plastic-adherent spleen cells from BCG-infected mice were cultured with normal spleen cells, a strong depression of their reactivity to phytohemagglutinin, concanavalin A, and lipopolysaccharide was observed. After the removal of cells adherent to plastic, the response was partially restored in the nonadherent population from mice infected i.p., but not in that from mice infected i.v. After mitogenic stimulation, lymph node cells of mice inoculated subcutaneously showed a response to mitogen higher than that of normal cells. These results thus demonstrate that, depending on the route of administration, BCG exerts very different effects.  相似文献   

5.
The anatomical progression of chlamydial infection was studied in different areas of the placenta, using a mouse model and two inoculation times: early pregnancy (day 7, group A) and midpregnancy (day 11, group B). The first population cells affected were decidual cells and neutrophils located just at the limits of the maternal and fetal placenta. The following invaded area was the layer of giant cells. Complete colonization of the maternal placenta occurred after day 15 of pregnancy independently of the inoculation time, the metrial gland being the last area to be invaded; numerous granulated metrial gland (GMG) cells were infected. Finally, chlamydial inclusions were observed in labyrinthine trophoblastic cells from day 18 of pregnancy onward. Since no fetal damage was observed, it seems that an indirect mechanism involving the lysis of GMG cells and neutrophil infiltration of the decidua and metrial gland may be the pathogenic mechanism that leads to abortion.  相似文献   

6.
Phytohaemagglutinin (PHA), Concanavalin A (Con A), interleukin-2 (IL-2), and monoclonal antibodies to CD3 (CD3MoAbs) are used for the assessment of the T-cell receptor (TCR) BV gene family expression in autoimmune disorders and multiple sclerosis, and to produce clones for assessment of cytokine profiles in progressive human immunodeficiency virus infection. The authors examined the effects of these stimulants on the TCR Vβ repertoire of resting and blastic CD4+ and CD8+ normal human peripheral blood lymphocytes, using three-colour cytofluorometry and a panel of anti-TCR Vβ monoclonal antibodies. IL-2 was associated with an increased percentage of blastic CD4+ cells expressing Vβ5.1 (from median of 3.7% to 8.0%, P  = 0.0002) and blastic CD8+ cells expressing Vβ5.3 (1.0 to 1.5%, P  = 0.0039). CD3MoAb caused a slight increase in Vβ6.7 + blastic CD4+ cells (4.5 to 6.9%, P  = 0.0078). PHA did not alter the Vβ repertoire of blastic cells. Con A caused skewing in CD8+ blastic cells, toward expression of Vβ5.2/5.3 (3.1 to 8.1%) and Vβ5.3 (0.8 to 4.8%) ( P  = 0.0020). Thus, IL-2 stimulation causes slight alterations in the Vβ repertoire that should be taken into account in certain research settings. Con A produced skewing in CD8+ blastic cells suggesting that, in the presence of CD8, either Con A binds selectively to certain Vβ or the three-dimensional complex created by Con A's binding to other T-cell surface molecules induces preferential Vβ5 stimulation.  相似文献   

7.
A case with lymphadenopathy of the left side of the neck in a 38-year-old male is described. He had a history of several relapses of about 10 years duration. Swollen lymph nodes were histologically similar to those of the hyaline-vascular type of Castleman's disease, but contained clear-cut lymph sinus and a sheet-like proliferation of plasma cells. Lymph follicles showed proliferation and atrophic germinal centers, in which cellular hypertrophy in the wall of ramifying small blood vessels, called angiosclerosis, was frequently encountered. During its progress, the patient developed plasmacytoma of the lymph nodes with varied clinical manifestations such as polyneuropathy, disturbance of gait, unusual perspiration, hirsuitism, gynecomastia, bilateral papilledema, and albumino-cytologic dissociation in cerebrospinal fluid.  相似文献   

8.
As a member of the Eph family of receptor tyrosine kinases, EphA7 plays an important role in cancer. However, the expression and significance of Eph receptors in esophageal squamous cell carcinoma (ESCC) remain unclear. Here, we detected the expression of EphA7 by immunohistochemistry in a sample of 352 patients with ESCC, and aimed to investigate the expression status of EphA7 in ESCC and its impact on prognosis. The results showed that low EphA7 expression significantly correlated with lymph node metastases (N0: 29%; N1: 64%. p<0.001), poor degree of tumor differentiation (G1: 31%; G2: 49%; G3: 58%. p=0.009) and pTNM staging (I+II: 33%; III+IV: 58%. p<0.001). Furthermore, in a combined analysis, patients with low EphA7-expressing tumors showed a shorter overall survival than those with high expression, resulting in a five-year overall survival rate of 47.4% vs. 52.6%, respectively (p=0.016). Consequently, patients with a low EphA7 expression have poorer prognosis in ESCC compared with those manifesting high expression.  相似文献   

9.
使用抗CD3单抗诱导新鲜分离的人外周血单个核细胞(PBMC)凋亡,同时观察细胞因子对其影响。18h后电镜发现处理组发生典型凋亡改变,DNA电泳出现典型阶梯状条带。TUNEL法流式细胞仪检测发现处理组凋亡发生率39.6%,显著高于对照组(<0.01)。IFN-7/TNF-a可显著增强抗CD3单抗诱导的凋亡。IL-1~IL-3、TNF-=对凋亡无明显影响。CsA可抑制抗CD3单抗诱导的凋亡,但加入IFN-y则可完全逆转这种作用。结果表明抗CD3单抗可诱导PBMC发生凋亡,IFN-Y、TNF-与抗CD3有协同作用。  相似文献   

10.
The present study has examined the effects of arborinine, an alkaloid obtained from Erthela bahiensis, a Brazilian plant popularly used as diuretic, antidiabetic, antithermic and expectorant, on the viability and function of immune system cells in vitro using a murine model. Rat spleen and thymus cells were cultured with 10nM, 1µM e 10µM of the drug in the presence or absence of pokeweed (PWM), lipopolysaccharide (LPS), or concanavallin (ConA) mitogens. Cellular proliferation was analyzed by H3‐thymidin uptake after 48 and 72 hr. Our results showed an inhibitory effect of arborinine on splenocytes proliferation under ConA or PWM stimulation and increased apoptosis on splenocytes and thymocytes stimulated with PWM in 24 hr. A decrease was observed on Interferon gamma (IFN-γ) production by ConA- or LPS-stimulated splenocytes in 48 hr and 72 hr and ConA- or PWM-stimulated thymocytes in 72 hr. In contrast, an increase on lymphoproliferation was observed on LPS-stimulated splenocytes and ConA- or PWM-stimulated thymocytes in 48 hr. On this period, apoptosis decreased on LPS- or PWM-stimulated splenocytes and IFN-γ production increased in PWM stimulated thymocytes. Arborinine also induced a decrease on Interleukin-10 production by splenocytes and thymocytes stimulated with ConA or PWM. There was no significant variation on the necrosis rate of the cells treated with arborinine or any change on their viability or function values in the absence of mitogenic stimulus.  相似文献   

11.
The aim of this study was to investigate how patterns of lymph nodes recurrence after radical surgery impact on survival of patients with pT1-3N0M0 thoracic esophageal squamous cell carcinoma. One hundred eighty consecutive patients with thoracic esophageal squamous cell carcinoma underwent radical surgery, and the tumors were staged as pT1-3N0M0 by postoperative pathology. Lymph nodes recurrence was detected with computed tomography 3-120 months after the treatment. The patterns of lymph nodes recurrence including stations, fields and locations of recurrent lymph nodes, and impacts on patterns of survival were statistically analyzed. There was a decreasing trend of overall survival with increasing stations or fields of postoperative lymph nodes involved (all P<0.05). Univariate analysis showed that stations or fields of lymph nodes recurrence, and abdominal or cervical lymph nodes involved were prognostic factors for survival (all P<0.05). Cox analyses revealed that the field was an independent factor (P<0.05, odds ratio=2.73). Lymph nodes involved occurred predominantly in cervix and upper mediastinum (P<0.05). In conclusion, patterns of lymph node recurrence especially the fields of lymph nodes involved are significant prognostic factors for survival of patients with pT1-3N0M0 thoracic esophageal squamous cell carcinoma.  相似文献   

12.
In the Local Lymph Node Assay (LLNA), a stimulation index of 3 (SI = 3) is established as a threshold value for hazard identification of sensitization. The corresponding EC3 value, the effective concentration inducing a threefold increase compared to controls, can possibly predict threshold levels for sensitization in humans. Exposure to a dose below the threshold dose would not result in an induction of an immune response. Each repeated contact would be considered and viewed as a new contact and as long as the dose is below the threshold there will be no response, even after repeated exposures. However, repeated exposure may result in local accumulation eventually resulting in a dose that induces a response above the threshold for immunization. We investigated lymph node responses after short and prolonged exposure to formaldehyde donors, chemicals that are highly reactive with proteins and may thus persist in the skin. The studies were performed with formaldehyde and formaldehyde releasers (formaldehyde, paraformaldehyde, Quaternium-15, 2-Chloro-N-(hydroxymethyl)acetamide, and hexamethylenetetramine), at concentrations that induce a SI = 2, i.e., below the threshold for hazard identification. For all test chemicals investigated enhanced lymph node responses were obtained when comparing long-term prolonged exposure to short-term exposure, while three of five chemicals induced responses above SI = 3. Our results show that repeated and prolonged exposure to doses below the EC3 value can induce reactions above the SI = 3, the hazard identification threshold for sensitization in mice. So, when discussing the possible use of the EC3 as benchmark for risk assessment, one should consider duration of exposure and the possibility of local accumulation of the chemical under investigation.  相似文献   

13.
14.
The expression of I-Ak antigens in normal C3H/FeJ adult and 15-day embryonic mice has been investigated by indirect immunofluorescence staining of tissue cryostat sections with the anti I-Ak antigen monoclonal antibody 10-2.16. In adult mice I-Ak antigens were expressed in Langerhans-like cells in the skin, epithelium of the gastrointestinal tract, endometrium, thymic reticuloepithelial cells, and several capillary endothelia. On the other hand, these antigens were not detected in Kupffer cells, alveolar macrophages, brain or mammary gland. In 15-day-old embryos the expression of Ia-like antigens was restricted to thymic reticuloepithelial cells, isolated spleen cells, and capillaries of the gastrointestinal tract.  相似文献   

15.
In previous studies, we have shown that intact, heat-killed, gram-negative bacteria (GNB) and gram-positive bacteria (GPB) can stimulate the production of various proinflammatory and anti-inflammatory cytokines. The objective of the present study was to investigate whether the production of tumor necrosis factor alpha (TNF) and interleukin-10 (IL-10) by human monocytes stimulated by intact heat-killed or live Haemophilus influenzae or Streptococcus pneumoniae is mediated by CD14. Two anti-CD14 monoclonal antibodies (MAbs) were used to study the interaction between human monocytes and bacteria; lipopolysaccharide (LPS) was used to validate the effect of anti-CD14 MAb. MAb 18E12 decreased significantly TNF and IL-10 production upon stimulation with LPS or heat-killed bacteria and TNF production during stimulation by live bacteria. MAb My-4 decreased production of TNF and IL-10 by monocytes stimulated with LPS, IL-10 but not TNF production upon stimulation with heat-killed H. influenzae, and production of neither TNF nor IL-10 upon stimulation with S. pneumoniae. Together, these results led to the conclusion that CD14 is involved in the recognition and stimulation of human monocytes by intact GNB and GPB. Consequentially, the option for adjunctive treatment of severe infections with anti-CD14 MAb is postulated.  相似文献   

16.
目的:利用逆转录聚合酶链扩增检测胃癌常规病理检查阴性的淋巴结微转移的发生及与免疫组化结果的关系。方法:利用逆转录聚合酶链反应(RT—PCR)方法检测480枚胃癌胃周淋巴结癌胚抗原(CEA)mR-NA基因表达,同时比较RT—PCR与免疫组化方法的检测敏感性。结果:利用TT—PCR检测CEA mRNA是一种很敏感的方法。检测138例胃癌患者取材的480枚胃周淋巴结。免疫组化阳性率27.5%(132/480)。RT—PCR阳性率58.8%(282/480),两组之间有显著性差异(P〈0.01);RT—PCR阳性率随着病期进展而增大。结论:RT—PCR技术是比免疫组化更敏感的方法,可以预测胃癌病人淋巴结微转移,有效避免已有微小转移的患者被漏诊、误诊。  相似文献   

17.
A peptide based on the complementarity determining region (CDR) 3 of a pathogenic anti-DNA monoclonal antibody that bears the 16/6 idiotype (Id) was shown previously to be a dominant T-cell epitope in experimental SLE, and to be capable of inhibiting SLE-associated responses. When injected, concomitant with active immunization with the pathogenic human anti-DNA, 16/6 Id + mAb, pCDR3 inhibited the proliferation of LN-derived T cells stimulated in vitro with the 16/6 Id mAb. The inhibition of the specific proliferative responses could be reversed by the addition of exogenous IL-2 to the cultures. Analysis of secreted cytokine profile in supernatants of these cultures demonstrated that pCDR3 treatment reduced significantly the levels of both IL-2 and IFN- &#110 that were elevated further in cells of the 16/6 Id-immunized mice. The CDR3-based peptide was shown here to immunomodulate in vivo experimental SLE, induced by the human anti-DNA 16/6 Id + antibody. The beneficial effects of pCDR3 on the clinical manifestations of SLE were associated with downregulation of the Th1-type (IL-2, IFN- &#110 ) and proinflammatory (TNF- &#102 ) cytokines, whereas the immunosuppressive cytokine TGF- &#103 was up regulated.  相似文献   

18.
Aims: To investigate the effect of Notch2 and Notch3 on cell proliferation and apoptosis of two trophoblast cell lines, BeWo and JAR.Methods: Notch2 and Notch3 expression in BeWo and JAR cells was upregulated or downregulated using lentivirus-mediated overexpression or RNA interference. The effect of Notch2 and Notch3 on cell proliferation was assessed by the CCK-8 assay. The effect of Notch2 and Notch3 on the apoptosis of BeWo and JAR cells was evaluated by flow cytometry using the Annexin V-PE Apoptosis kit. Lentivirus-based overexpression vectors were constructed by cloning the full-length coding sequences of human Notch2 and Notch3 C-terminally tagged with GFP or GFP alone (control) into a lentivirus-based expression vector. Lentivirus-based gene silencing vectors were prepared by cloning small interfering sequences targeting human Notch2 and Notch3 and scrambled control RNA sequence into a lentivirus-based gene knockdown vector. The effect of Notch2 and Notch3 on cell proliferation was assessed by the CCK-8 assay. And the effect of Notch2 and Notch3 on the apoptosis of BeWo and JAR cells was evaluated by flow cytometry using the Annexin V PE Apoptosis kit.Results: We found that the downregulation of Notch2 and Notch3 gene expression in BeWo and JAR cells resulted in an increase in cell proliferation, while upregulation of Notch3 and Notch2 expression led to a decrease in cell proliferation. Moreover, the overexpression of Notch3 and Notch2 in BeWo and JAR cells reduced apoptosis in these trophoblast cell lines, whereas apoptosis was increased in the cells in which the expression of Notch3 and Notch2 was downregulated.Conclusions: Notch2 and Notch3 inhibited both cell proliferation and cell apoptosis in BeWo and JAR trophoblast cell lines.  相似文献   

19.
PROBLEM: T cells bearing αβ T cell receptor (TcR) and γδ TcR are present at the fetomaternal interface, and the latter, which express surface activation markers, can react with fetal trophoblast cell antigens. What is the role of these cells? METHOD: Using stress-abortion-prone DBA/2-mated CBA/J and abortion-resistant C57/B16 mice, αβ, γδ, and CD8+/- T cell subsets were measured in spleen and uterine decidua. The effect of immunization against abortion and administration of anti-TcR antibody in vivo was examined. Cytokine synthesis was measured by intracellular staining of Brefeldin A-treated cells. RESULTS: Abortion-prone matings showed an unexpected accumulation of γδ T cells beginning in the peri-implantation period and this was suppressed by immunization against abortion. The immunization deleted γδ T cells producing the abortogenic cytokines, TNF-α and γ-interferon, and increased production of the anti-abortive cytokines, IL-10 and transforming growth factor-β2 (TGF-β2). Immunization also boosted the number of αβ T cells which were present in the decidua as early as 2 days after implantation. In vivo injection of GL4 (anti-δ) depleted γδ T cells producing Th1 cytokines in the peri-implantation period, and prevented abortions, whereas H57 (anti-β) decreased the number of αβ T cells and led to 100% abortions. CD8+ T cells present in peri-implant decidua before onset of abortions were mostly αβ TcR+, although some were γδ+. Changes in γδ and αβ T cells in pregnancy were most dramatic in uterine tissue. CONCLUSION: Although decidual γδ T cells after formation of a distinct placenta and fetus produce anti-abortive TGF-β2-like molecules and IL-10, prior events can lead to abortion. High local production of TNF-α and γ-interferon develop during the peri-implantation phase because of an excessive increase in the Th1 cytokine+ subset of γδ cells; these cytokines may be contributed by other tissues in decidua, and the contribution of bioactive factors by γδ T cells may augment the cytokine pool. In contrast, αβ T cells (which may be inactivated by stress that causes abortions) may mediate the anti-abortive effect of alloimmunization. Alloimmunization involves a shift from a Th1 to a Th2 pattern in the γδ T cells in decidua.  相似文献   

20.
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