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71.
Frozen-stored human spleen cells (SC) cultured with streptococcus preparation OK-432 acquired direct cytotoxicity to autologous as well as allogeneic tumor cells. The activated cells started to produce cytocidal cytokine TGIF, which is distinct from previously known cytokines.We examined the possibility of allogeneic adoptive immunotherapy (AIT) using these OK-432-stimulated spleen cells (OK-SC) in two cancer patients. Rapid necrosis of cancer tissue and remarkable decreases of tumor markers in tumor effusion were observed. There were no severe side effects.  相似文献   
72.
Summary Rat kidney and spleen glucosyl-galactosyl-hydroxylysine glucosidase (EC.3.2.1.107) whose specificity for the hydroxylysine-linked disaccharide units present in collagens depends upon the substrate's free amino group was tested for its glycosidase activity on the ketoamine form of glycated [14C]Glc-Globin. The most stable preparations of the enzyme from normal and diabetic rat tissues, partially purified by ultracentrifugation and ammonium sulphate fractionation, were used. These glucosidase preparations did not release any significant amount of radioactive neutral hexose. But a radioactive glycopeptide of about 1,400 Da was released from [14C]Glc-Globin at a pH optimum of 4.0. It appears to be released by a peptidase activity present in the kidney and spleen of normal and diabetic rats.  相似文献   
73.
Summary Non-lymphoid cells (marginal metallophils, follicular immunecomplex-retaining cells, interdigitating cells), which are present in certain areas of the white pulp in the mouse spleen were characterized by means of (immuno)enzyme histochemical techniques, carbon uptake and experiments with lethal X-irradiation. Marginal metallophils are clearly present at the inner border of the marginal zone and show a very strong, E-600 sensitive, non-specific esterase (NSE) activity. Follicular immune-complex-retaining cells show a weak and diffuse NSE activity and no carbon uptake as shown by the combined application of an immunohistoperoxidase technique (for the demonstration of immune complexes), enzyme histochemistry (for NSE activity) and carbon uptake (for phagocytosis). Interdigitating cells show a distinct focus of NSE activity in the cytoplasm, weak carbon uptake and high radiation sensitivity. Demonstration of NSE activity is useful for the identification of the different non-lymphoid cells in the white pulp of the mouse spleen. It is suggested that the in vitro observed dendritic cells of Steinman and Cohn (1973) belong to the mononuclear phagocyte system, as transitional cells are encountered with cytological features of both dendritic cells and macrophages. These in vitro dendritic cells (or a portion of them) are probably similar to the interdigitating cells.Abbreviations HRP horseradish peroxidase - IDC interdigitating cells - PALS periarteriolar lymphocytic sheath - NSE non-specific esterase  相似文献   
74.
The recovery of the B lymphocyte compartments was investigated in lethally irradiated mice reconstituted with fetal liver cells. This was done by means of immunofluorescence on frozen sections of spleen, lymph nodes and Peyer's patches. The first B lymphocyte recovery in the spleen was observed on day 8, a few days earlier than in lymph nodes and Peyer's patches (day 13). These early B cells in the spleen were found in the central part of the periarteriolar lymphatic sheath (PALS). Later on, while increasing in number, the B cells formed growing follicles at the periphery of the PALS. Subsequently, brightly fluorescent B cells appeared in the marginal zone, which surrounded the follicles. Another two weeks later, around day 30, also germinal center formation was observed in the follicles of the spleen. B cell development in lymph nodes and Peyer's patches started somewhat later than in the spleen, but once started, the recovery of the different compartments was completed very fast. Germinal center reactions were found in lymph nodes and Peyer's patches already on day 25, and thus earlier than in the spleen, but later than the first occurrence of the strongly fluorescent cells in the marginal zone. Apparently, germinalcenter formation is not essential for the recovery of the population of brightly fluorescent B cells in the marginal zone after irradiation and reconstitution.  相似文献   
75.
Mixed lymphocyte reactions and in vitro antibody responses to dinitrophenol (DNP) after immunization with DNP-Ficoll were measured in spleen cells from mice following infection with 200 Trichinella spiralis larvae. A depression of the mixed lymphocyte reaction was observed at 14 through 84 days after infection. A reduced response to concanavalin A stimulation was demonstrated over a similar time period, 7 through 63 days of infection. The addition of mitomycin C-treated spleen cells from mice infected with T. spiralis to cultures of normal splenocytes suppressed the mixed lymphocyte reaction by 28% to 65%. The antibody response to DNP-Ficoll immunization was enhanced 20 days after infection, a time when the T-dependent antibody response to sheep erythrocytes was depressed.  相似文献   
76.
The kinetics of infection with Theileria parva in cattle were studied by examining the total cellularity and numbers of parasites in a range of lymphoid organs from animals killed at intervals during the course of the infection. With the dose of T. parva stabilate used, macroschizonts were initially detected in the drainage lymph node about 7 days after inoculation and death of the host resulted on Day 18–19. Associated with the initial detection of parasites, there was a marked increase in cellularity of the drainage lymph node and a more gradual and less pronounced increase in cellularity of the other lymphoid organs. From about Day 12 onward, there was a gradual decrease in the cellularity in all of the lymphoid organs, so that in animals examined in the terminal stages of the infection there was often cellular depletion. The pattern of these cellular changes was similar in groups of Boran and Friesian cattle, although both the increase in cellularity and the terminal depletion were more marked in the Friesians. Blood leukocyte counts in infected Boran started to drop as early as Day 7 of infection and by Day 14 had reached values less than 25% of normal. Quantitation of parasitic schizonts indicated that the numbers of parasites in the lymphoid organs do not increase in a simple exponential manner. Rather, there appears to be an early rapid increase in parasite numbers followed by a phase of less rapid multiplication. Because of the marked changes which occured in total cellularity of the lymphoid organs during the course of the infection, a significant discrepancy was found between the replication rate of the parasite as calculated using total numbers of parasites and that obtained using schizont index (SI). These results indicated that the use of SI, as described in previous studies, is not a reliable method of determining the replication rate of the parasite.  相似文献   
77.
Following primary in vitro Stimulation by Plasmodium berghei, IgM titers by the indirect fluorescent antibody test (IFAT) were negative in in vitro reconstituted syngeneic mouse spleen cultures containing T cells and macrophages, or B cells and macrophages, or macrophages alone, but IgM titers of 1:20 were obtained from cultures containing B cells, T cells, and macrophages. IFAT IgG titers were negative for cultures with T cells and macrophages together, or macrophages alone, but rose to 1:40 with cultures containing B cells and macrophages and 1,80 with cultures of B cells, T cells, and macrophages together. After a second in vitro challenge, IgM and IgG titers were similar to the stimulated cultures from immunized mice; the IgM titer reached only 1:20 but the IgG titer rose to 1:160. Total immunoglobulin was higher in the cultures from immunized mice than from in vitro primed cultures.  相似文献   
78.
Summary The structural characteristics and cellular elements of the boundary zone between the white and red pulp of the human spleen were studied by SEM and TEM. The boundary zone consisted of both the perifollicular region and the region surrounding the periarterial lymphoid sheath. The perifollicular region was further subdivided into two, equally thick layers. The inner half layer of the perifollicular region outside the mantle zone of the lymph follicle was composed of tightly packed medium-sized lymphocytes, interspersed by a small number of reticular cells. The outer half layer was composed of a reticular cell meshwork containing blood cells in vessels, which communicated with the splenic cords of the red pulp. Intermittent rows of reticular cells distinguished the outer from the inner half layer. The region surrounding the periarterial lymphoid sheath revealed the same type of reticular cell meshwork as the outer half layer of the perifollicular region. Capillary ends opened into the reticular cell meshwork, which suggested the presence of an open circulation in the human spleen. A deep lymphatic vessel which communicated with the periarterial lymphoid sheath was noted.  相似文献   
79.
FGF-1改构体对小鼠脾细胞增殖与凋亡的影响   总被引:3,自引:1,他引:2  
目的:主要探讨非促分裂改构人酸性成纤维细胞生长因子(MrhFGF-1)对balb/c小鼠脾细胞增殖和凋亡的影响。方法:采用3H-TdR掺入的方法检测MrhFGF-1同野生型hFGF-1相比对脾细胞增殖的影响,实验组分为(1)对照组;(2)FGF-1处理组;(3)ConA处理组;(4)FGF-1+ConA处理组。用流式细胞仪定量分析MrhFGF-1对脾细胞的凋亡保护作用,(1)对照组;(2)DEX处理组;(3)DEX+FGF-1(hFGF-1、rhFGF-1、MrhFGF-1)处理组。结果表明,利用DNA重组技术构建的一种非促分裂FGF-1突变体MrhFGF-1和野生型FGF-1相比,对脾细胞的促细胞增殖能力明显降低,但其对细胞凋亡保护作用的影响并无显著性变化,说明FGF-1的促细胞增殖能力和细胞凋亡保护信号通路并非由同一信号通路来实现的。  相似文献   
80.
胃肠宁对利血平所致大鼠脾虚模型的影响   总被引:1,自引:0,他引:1  
目的 观察胃肠宁对大鼠脾虚证模型的影响.方法 36只大鼠随机分为正常对照组、脾虚模型组、四君子汤组和胃肠宁组,每组9只.采用利血平复制大鼠脾虚模型,连续灌胃14 d后,处死大鼠,分离肝、十二指肠和血清,测定各组大鼠血浆LDH、AKP、AchE、CK和肝组织匀浆中SOD、MDA、GSH-Px、NOS含量变化,并观察各组大...  相似文献   
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