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41.
FAS receptor (FAS, CD95) and FAS ligand (FAS-L, CD95-L) are complementary members of a particular apoptotic pathway that plays a major role in immune regulation. The activation of FAS-L may trigger cytotoxic mechanisms leading to the death of FAS-expressing cells. Tumor cells and tumor-infiltrating lymphocytes (TIL) may express FAS and FAS-L in various proportions, and their interplay may affect tumor behavior. In the present study, we explored the expression of FAS and FAS-L in 28 mammary carcinomas (19 ductal and 9 lobular) and in their lymph node metastases. The expression of these mediators in immunostained sections was graded and evaluated comparatively between normal and neoplastic mammary epithelium, between tumor cells and TILs, and between mammary carcinoma cells and their lymph node metastases. We demonstrated the coexpression of FAS and FAS-L by breast carcinoma cells and TIL, with FAS expressed more strongly by normal epithelial cells and TIL than tumor cells. FAS-L was better stained on tumor cells than on TIL. There was equal or greater expression of FAS and FAS-L in the primary tumors and their TIL than in the metastatic counterparts. Comparing the expression of FAS with that of FAS-L, we recorded FAS equal or stronger than FAS-L in the primary mammary tumors and the reversal of their expression, FAS-L greater than FAS in the lymph node metastases. These results are consistent with reports of studies with other tumors, suggesting that the upregulated FAS-L indicates an increased ability of tumor cells to induce apoptosis in TIL and in the normal tissues invaded. However, it is understood that the FAS/FAS-L system, although essential for apoptosis, is only a contributing factor to the complex process of tumor invasion and antitumor defense.  相似文献   
42.
淋巴结血管内T细胞淋巴瘤1例报道及文献复习   总被引:1,自引:0,他引:1  
目的 探讨血管内淋巴瘤 (IVL)的临床病理特征。方法 对 1例腹股沟淋巴结IVL临床、病理组织学及免疫表型进行观察分析并复习文献。结果 男性 31岁 ,不明原因高热伴消瘦 5 0天 ,右腹股沟直径 1cm淋巴结 1枚 ,B超示肝脏轻度增大 ,血LDH明显升高伴ESR及转氨酶轻度升高 ,外周血WBC 3 3× 10 7/L ,骨髓像、多种病原及各肿瘤相关抗原检测均无异常。病理活检 :腹股沟淋巴结大部分破坏 ,代之以大量扩张的中小血管 ,腔内充满大量异型淋巴样细胞 ,局部伴管壁、管周浸润并累及结外脂肪组织。瘤细胞免疫表型CD4 5、CD4 5RO、CD3阳性 ,CK、CD6 8、CD79α、CD2 0均阴性 ,血管壁及内皮细胞CD31、CD34阳性。行CHOP化疗后症状缓解 ,现仍在随访中。结论 IVL是一罕见的非霍奇金淋巴瘤 ,好发于中枢神经系统及皮肤 ,其他部位少见 ,绝大数为B细胞型 ,T型罕见 ,以浅表淋巴结活检确诊者尚无报道。临床表现有一定提示性 ,确诊靠组织病理学检查 ,部分病例对化疗敏感 ,但多数病例预后差  相似文献   
43.
Inflammatory pseudotumors (IPTs) of the lymph node and spleen are an uncommon, benign cause of lymphadenopathy and/or splenomegaly that often bear striking clinicopathologic similarities to the inflammatory myofibroblastic tumors (IMTs) found in soft tissues. These tumors have classically been grouped together under the umbrella category of "inflammatory pseudotumor." Recent evidence shows that IMTs are in fact neoplastic processes that often harbor balanced chromosomal translocations involving the ALK kinase gene. These translocations result in expression of ALK kinase in IMTs as assessed by immunohistochemical studies. However, the relationship between IMT and IPT of the lymph node and spleen is uncertain. To determine if ALK tyrosine kinase expression is also present in IPT, 13 cases of IPT (9 involving lymph nodes, 4 splenic lesions) were examined for the presence of ALK tyrosine kinase by immunohistochemical staining on paraffin-embedded tissue. In addition, in situ hybridization studies for Epstein-Barr virus--encoded RNAs (EBER) and immunoperoxidase studies for human herpesvirus-8 (HHV8)--specific proteins were performed. All cases had clinical, morphologic, and immunophenotypic findings typical of IPT and had varying proportions of fibroblastic and inflammatory components. Age ranged from 11 to 75 (median, 40) years; 8 subjects were male, and 5 were female. None of the cases (0 of 13) had positive staining for ALK kinase or HHV8, and in 1 a lymph node (1 of 13) was focally positive for EBV (EBER) by in situ hybridization. The absence of ALK kinase as detected by immunohistochemical studies in IPT of the lymph node and spleen suggests that this entity is biologically distinct from the histologically similar IMT.  相似文献   
44.
The receptor, c-kit, and its ligand, stem cell factor (SCF), are important regulators of ovarian follicle growth and development. The aim of this study was to identify the sites of expression of mRNA for c-kit and SCF in prepubertal and mature (pregnant and non-pregnant) animals. Ovaries were recovered from prepubertal animals, non-pregnant sows and five sows at approximately 3 months of gestation. Ovine SCF and c-kit DNA were cloned into plasmid vectors to produce RNA probes. Expression of mRNA encoding SCF and c-kit were detected via in situ hybridization. Both mRNA were detected throughout ovaries from all animals. This study provides evidence that the growth-factor complex is required throughout follicle development, and also for continued maintenance of the corpus luteum (CL) in the mature animal. SCF mRNA was localized to the granulosa cell layer and was also extensively expressed in endothelial tissue and throughout the CL. c-kit mRNA was detected in the theca layer, oocytes and also in CL. In conclusion, expression of SCF and c-kit mRNA in granulosa and theca cells, respectively, indicate an important interaction between somatic cells throughout follicle development and that in the mature animal, SCF and c-kit potentially have a role in maintaining progesterone secretion by the CL. The observations of continued expression of SCF and c-kit throughout development suggest that there may be differences in the role of this receptor-ligand complex between large mono- vs. poly ovulatory species, such as the pig.  相似文献   
45.
We investigated the association between human leucocyte antigen (HLA) antigens and lymph node metastasis in 724 gastric cancer patients. Among patients who had poorly differentiated adenocarcinoma with or without HLA-DR4 antigen, lymph node metastasis was detected in 80.8 and 54.9%, respectively (relative risk (RR)=3.5, P = 0.0005, corrected P = 0.0285). It was more common in patients with a family history of cancer death (RR = 7.7). Among signet ring cell carcinoma patients with or without HLA-1152 antigen, lymph node metastasis was detected in 57.7 and 19.7%, respectively (RR =5.6, P=0.0001, corrected P=0.0086). It was more common in patients who were smokers (RR = 8.3). Our findings suggest that HLA-DR4 and HLA-1152 antigens are associated with lymph node metastasis in gastric cancer.  相似文献   
46.
The occurrence of pregnancy-associated endometrial alpha 1-globulin (alpha 1-PEG), a 29-32 kd insulin-like growth factor binding protein, now termed type 1 or IGF-bp1, has been examined in the human ovary by monoclonal and polyclonal antibody based radioimmunoassay and immunohistological techniques. Follicular fluids aspirated from 51 follicles of 32 women undergoing hyperstimulation involving buserelin or clomiphene-based protocols contained 35.5-276.0 ng/ml (mean 101.0 mg/ml) of immunoreactive IGF-bp1. Mean fluid concentrations were three times the level of IGF-bp1 detected in paired serum samples, available for 21 women. Immunoreactive IGF-bp1 in follicular fluid exhibited similar dose-response curves to purified protein and amniotic fluid and immunoreactive IGF-bp1 coeluted in gel filtration with a peak of [125I]-IGF-1 binding corresponding to the elution profile of purified IGF-bp1. Gel filtration also revealed the presence in follicular fluid of a greater than 100 kd binding protein with a binding capacity equal to IGF-bp1 under the conditions employed. A highly significant correlation (P less than 0.001) was found between follicular fluid progesterone and IGF-bp1 and a correlation of lower significance was found between oestradiol and IGF-bp1 (P less than 0.05). However, only low levels of immunoreactive IGF-bp1 were detected in supernatant media of granulosa cells in culture (range undetectable to 2.3 ng/ml). Employing monoclonal antibody-based immunohistology, immunoreactive IGF-bp1 was consistently associated with luteinized granulosa cells of corpora lutea rather than paraluteal cells and its intensity of reactivity appeared to reflect luteal phase steroid hormone profiles. No consistent reactivity was detected in preovulatory follicles and granulosa cells in culture, although reactivity was associated with primordial oocytes. Immunoreactive IGF-bp1 was detected in six of nine supernatant media of explants of luteal tissue obtained from five corpora lutea, with levels ranging from undetectable to greater than 200 ng/ml. These observations suggest that IGF-bp1 is primarily related to luteinization of the granulosa and the resultant luteal cells, and if produced by the luteal cells, additional exogenous factors are required to induce production by granulosa cells in vitro.  相似文献   
47.
Cell mediated lympholysis (CML) has been proposed as an in vitro model of the rejection process that results from transplantation of allogeneic tissue. To date, the absolute frequencies of cytotoxic T lymphocytes (CTL) and their precursors (CTL.P) have not been directly estimated in man because of technical difficulties. Through optimizing the conditions for radiometric detection of 51Cr release and the attendant improvement in CML sensitivity, direct CTL frequency estimates have been determined in peripheral blood (PBL), spleen (SPL), and lymph nodes (LNC) after in vitro allostimulation using unrelated human cells and limiting dilution assays. The mean frequency of CTL generated from PBL is 1 in 826 cells (0.121% +/- 0.101%) which, from preliminary experiments, is significantly greater than that generated from either LNC or SPL (p less than 0.05). With restimulation of primed cells on day 10, the frequency of CTL generated from PBL was increased 400%. The CTL.P frequency (0.0064% +/- 0.0050%) was approximately 5% of the corresponding CTL frequency. The CTL.P frequencies were found to be minimal estimates as both accessory "filler" cells and T cell growth factors increased the level of detection of CTL.P an average of threefold. The limiting cell dilution assay as detailed in this report should be a powerful tool for defining the cellular requirements and related factors necessary for optimal induction of a CTL response and should provide the means for determination of the immunogenetic requirements and the allospecificity of human cytotoxic lymphocytes.  相似文献   
48.
The inducible adhesion molecules mediate important functions in the lymphoid tissues. We have investigated the expression of intercellular adhesion molecule 1 (ICAM-1), endothelial leucocyte adhesion molecule 1 (ELAM-1), vascular cell adhesion molecule 1 (VCAM-1), and platelet endothelial cell adhesion molecule (PECAM/CD31), using immunocytochemistry on cryostat sections of five lymph nodes from patients with Castleman's disease of the hyaline-vascular type. All five cases were characterized by marked hyperplasia of follicular dendritic reticulum cells, which were extensively present even in the mantle zone. Hyperplastic follicular dendritic reticulum cells showed marked expression of VCAM-1, and weak expression of ICAM-1. In two cases, several dysplastic giant cells with aberrant, polyploid nuclei showed aberrant expression of ELAM-1, an endothelium-restricted molecule. Dysplastic giant cells were positive with DRC-1 (an antibody to dendritic reticulum cells), VCAM-1 and occasionally ICAM-1, were negative for the endothelial cell markers factor VIII-related antigen and CD31 and were non-proliferating (Kl-67-). Cells positive for ICAM-1 or VCAM-1 were rare in the interfollicular areas. In all cases vascular hyperplasia was prominent, but endothelial cells were poorly activated in terms of expression of inducible adhesion molecules and of HLA-DR antigens. The possibility that dysplastic follicular dendritic reticulum cells have a pathogenetic role in Castleman's disease is discussed.  相似文献   
49.
We diagnosed tuberculosis in an illegally wild-captured pet ring-tailed lemur manifesting lethargy, anorexia, and cervical lymphadenopathy. Whole-genome sequencing confirmed the Mycobacterium tuberculosis isolate belonged to lineage 3 and harbored streptomycin resistance. We recommend reverse zoonosis prevention and determination of whether lemurs are able to maintain M. tuberculosis infection.  相似文献   
50.
目的 探讨X线照射对小鼠月国窝淋巴结淋巴滤泡的影响。方法 采用组织学、免疫组织化学及三维重塑技术 ,观察小鼠全身X线照射后月国窝淋巴滤泡的变化。结果 小鼠全身X线照射后月国窝淋巴结重量迅速减小 ,淋巴细胞数量下降 ,淋巴滤泡被破坏。结论 X线照射可破坏淋巴滤泡 ,并经过一定时期可以重新聚集 ;再构筑的淋巴滤泡不是新产生的而是受损淋巴滤泡再生形成的  相似文献   
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