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41.
Application of Serum-Free Culture Medium for Preparation of A-NK Cells   总被引:4,自引:0,他引:4  
To compare the differences between proliferation and cytotoxicity of adherent natural killer (A-NK) cells cultured with serum-free medium AIMV and standard serum-containing medium in vitro, and also observe the assisting effect of IL-12 on the activation and the morphology character of IL-2-treated A-NK cells, cellular proliferation was evaluated by MTT method in vitro. The morphology of the target cells killed by A-NK cells was observed through electroscope. All of the A-NK cells cultured in serum-free medium AIMV could rapidly proliferate and keep high cytotoxicity compared with that in standard serum-containing medium. A-NK cells activated by both moderate-dose IL-2 and IL-12 were superior to the high-dose IL-2-treated A-NK cells. These data indicated that serum-free medium AIMV could replace standard serum-containing medium for culturing A-NK cells, and moderate-dose IL-2 and IL-12 could reduce side effects caused by high-dose IL-2. The study provided a new experimental basis for experimental and clinical preparation of A-NK cells. Cellular & Molecular Immunology.  相似文献   
42.
CD69, known as an early activation marker antigen on T and B cells, is also expressed on platelets and activated neutrophils, suggesting certain roles in inflammatory diseases. In order to address the role of CD69 in the pathogenesis of arthritis, we established CD69-null mice. CD69-null mice displayed a markedly attenuated arthritic inflammatory response when injected with anti-type II collagen antibodies. Cell transfer experiments with neutrophils, but not T cells or spleen cells, from wild-type mice into CD69-null mice restored the induction of arthritis. These results indicate a critical role for CD69 in neutrophil function in arthritis induction during the effector phase. Thus, CD69 would be a possible therapeutic target for arthritis in human patients.  相似文献   
43.
Brachydactyly type A (BDA) is defined as short middle phalanges of the affected digits and is subdivided into four types (BDA1‐4). To date, the molecular cause is unknown. However, there is some evidence that pathogenic variants of HOXD13 could be associated with BDA3 and BDA4. Here, we report a Chinese autosomal dominant BDA3 pedigree with a novel HOXD13 mutation. The affected individuals presented with an obviously shorter fifth middle phalanx. The radial side of the middle phalanx was shorter than the ulnar side, and the terminal phalanx of the fifth finger inclined radially and formed classical clinodactyly. Interestingly, the index finger was normal. The initial diagnosis was BDA3. However, the distal third and fourth middle phalanges were also slightly affected, resulting in mild radial clinodactyly. Both feet showed shortening of the middle phalanges, which were fused to the distal phalanges of the second to the fifth toes, as reported in BDA4. Therefore, this pedigree had combined BDA3 and atypical BDA4. By direct sequencing, a 13 bp deletion within exon 1 of HOXD13 (NM_000523.4: c.708_720del13; NP_000514.2: p.Gly237fs) was identified. The 13 bp deletion resulted in a frameshift and premature termination of HOXD13. This study provides further evidences that variants in HOXD13 cause BDA3‐BDA4 phenotypes.  相似文献   
44.
Comparative genomic hybridization (CGH) analyses have detected gains of copy number on 13q, especially at 13q31-q32, in cell lines and primary cases of various types of lymphoma. Since amplification of chromosomal DNA is one of the mechanisms that can activate tumor-associated genes, and because 13q amplification had been reported in various other types of tumors as well, we attempted to define by fluorescence in situ hybridization (FISH) a common region at 13q31-q32 in which to explore genes that might be targets for the amplification events. Although the commonly amplified region we defined was relatively large (approximately 4 Mb), only one true gene, GPC5, was found there. GPC5 was over-expressed in lymphoma cell lines that had shown amplification, in comparison with those that had not. Our findings suggest that GPC5 is a likely target for amplification, and that over-expression of this gene may contribute to development and/or progression of lymphomas and other tumors.  相似文献   
45.
IL-1 is a pro-inflammatory cytokine consisted of two molecular species, IL-1alpha and IL-1beta, and the IL-1 receptor antagonist (IL-1Ra) is a natural inhibitor of both molecules. Although it is suggested that IL-1 potentiates immune responses mediated by T(h)2 cells, the role of IL-1 in asthma still remains unclear. In this study, we demonstrate that the ovalbumin (OVA)-induced airway hypersensitivity response (AHR) in IL-1alpha/beta-deficient (IL-1alpha/beta(-/-)) mice was significantly reduced from the levels seen in wild-type mice, whereas the responses seen in IL-1Ra(-/-) mice were profoundly exacerbated, suggesting that IL-1 is required for T(h)2 cell activation during AHR. OVA-specific T cell proliferation, IL-4 and IL-5 production by T cells, and IgG1 and IgE production by B cells in IL-1alpha/beta(-/-) mice were markedly reduced compared with these responses in wild-type mice; such responses were enhanced in IL-1Ra(-/-) mice. Using IL-1alpha(-/-) and IL-1beta(-/-) mice, we determined that both IL-1alpha and IL-1beta are involved in this reaction. Both IgG1 and IgE levels were reduced in IL-1beta(-/-) mice, while only IgE levels were affected in IL-1alpha(-/-) mice, indicating a functional difference between IL-1alpha and IL-1beta. These observations indicate that IL-1 plays important roles in the development of AHR.  相似文献   
46.
IL-12家族新成员及其在免疫应答中的重要调节作用   总被引:3,自引:0,他引:3  
白细胞介素-12(Interleukin-12, IL-12)家族成员IL-12、 IL-23、 IL-27三者及其各自受体在结构上的相似性, 使得它们在发挥调节NK细胞活性、 T细胞增殖和细胞因子产生以及抗体类别转换等方面的功能相互重叠但又不完全相同.而2007年发现的该家族的另一新成员IL-35, 结构上虽与其他3个成员同源, 但却具有独特的生物学功能, 是一种主要由调节性T细胞(Treg)分泌的抑制性细胞因子.IL-12家族各成员以及同其他细胞因子之间存在着相互协同、相互拮抗的网络, 不仅在细胞内感染及炎症过程中起着重要的调节作用, 而且与银屑病、多发性硬化症、 Crohn' s病等多种临床疾病的发病密切相关.IL-12家族相关生物制品在自身免疫性疾病、感染性疾病以及肿瘤的治疗中有着广阔的应用前景.  相似文献   
47.
PROBLEM: To determine if interleukin-16 (IL-16), IL-17, and IL-18 are present at the murine fetomaternal interface during pregnancy as a first step towards investigating their roles in fetomaternal relationship. METHODS: Expression of IL-16, IL-17, and IL-18, was assessed by immunohistochemistry (IHC) in the BALB/c x BALB/k (H2d x H2k), and the CBA/J x BALB/c non-abortion prone, and CBA/J x DBA/2 abortion prone matings. Enzyme-linked immunosorbent assay (ELISA) were performed for the two latter cytokines to compare local production in the abortion prone CBA/J x DBA/2 versus the non-abortion prone CBA/J x BALB/c matings. RESULTS: Expression of IL-17 was borderline. The anti-IL-16 staining specifically localized in the uterine stroma and glandular epithelium and was rather low in the placenta. IL-18 staining started in the peri-implantation uterus in the basal proliferative stroma, and was also traced, although weaker, in the glandular epithelium. In the immediate post-implantation period, a weak stromal staining persisted but there was a strong labeling of the ectoplacental cone. Interestingly, when the ectoplacental cone differentiates into placenta having a major histocompatibility complex (MHC) class I + spongiotrophoblast and a (MHC class I-) labyrinth, a very strong transient labeling of uterine natural killer (u-NK) cells was found. Later in gestation, IL-18 was also produced by giant cell and spongiotrophoblast. Finally, we compared by ELISA the production of IL-17/-18 in CBA/J x DBA/2 and CBA/J x BALB/c matings. We detected significantly more IL-18 in the non-abortion prone combination decidua or placenta. CONCLUSION: The three cytokines IL-16, IL-17, and IL-18 were detected at the fetomaternal interface with a tissue specific, stage-dependent distribution. The predominance of IL-18 secretion in the non-resorption prone matings lead us to question the general validity of the classical T-helper (Th)1/2 paradigm.  相似文献   
48.
Pro-B cells are early B-cell progenitors that retain macrophage potential. We have studied MHC class II molecules and invariant chain inducibility on four class II negative mouse pro- B-cell clones. We analyzed the effects of IL-4 and IFN-γ, which represent the major inducers of class II in the B-lymphoid and monocytic/macrophage lineages, respectively. After 48 h of treatment with either cytokine, three pro-B-cell clones (C2.13, A1.5, and F2.2) expressed intracellular invariant chain and cell-surface class II molecules. One clone (D2.1) remained negative. As already reported, more differentiated 70Z/3 pre-B cells were inducible by IL-4 only. These data suggest that the induction of class II and invariant-chain genes are subject to regulation throughout B-cell differentiation.  相似文献   
49.
T regulatory cells-in addition to clonal deletion and anergy-are essential for the downregulation of T cell responses to both foreign and self antigens, and for the prevention of autoimmunity. Recent progress has been made in characterising the different subsets of T regulatory cells, the factors that drive their differentiation, and their mode of action. The resolution of these mechanisms will make it possible to use T regulatory cells therapeutically in human autoimmune diseases.  相似文献   
50.
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