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631.
Two monoclonal antibodies (To15 and 4KB128) specific for the B cell- associated CD22 antigen (135,000 mol wt) are described. On immunoenzymatic analysis of cryostat tissue sections, these antibodies strongly label both mantle zone and germinal center B lymphoid cells in secondary lymphoid follicles (and also scattered extrafollicular lymphoid cells) but are unreactive with other cell types (with the exception of weak reactivity with some epithelioid histiocytes). These reactions differ from those of monoclonal antibodies B1 and B2 (anti- CD20 and CD21) but are similar to those of the pan-B antibody B4 (anti- CD19). One of the anti-CD22 antibodies (To15) has been tested extensively by immunoenzymatic labeling on greater than 350 neoplastic lymphoid and hematological samples. The CD22 antigen was found in tissue sections in most B cell-derived neoplasms, the major exceptions being myeloma (all cases negative) and a small proportion of high-grade lymphoma (6% of cases negative). In cell smears, the antigen could be found on neoplastic cells in most B cell lymphoproliferative disorders, including common acute lymphoblastic leukemia (ALL) (90% positive) and B cell chronic lymphocytic leukemia (CLL) (89% positive). We conclude that anti-CD22 antibodies are of value for identification of human B cell lymphoproliferative disorders (especially when used in conjunction with anti-CD19 antibodies). Previous reports that the CD22 antigen is absent from many B cell neoplasms are probably due to its being expressed within the cytoplasm of immature B cells rather than on their surface.  相似文献   
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Both anti-single-stranded (ss) and anti-double-stranded (ds) DNA antibodies are associated with the autoimmune disease systemic lupus erythematosus (SLE), but only anti-dsDNA antibodies are considered one of the diagnostic criteria. Using Ig transgenes coding for anti-DNA we have determined the fate of anti-dsDNA B cells in a non-autoimmune environment. In a Rag-2 wild-type background, B cells expressing the anti-dsDNA Ig transgenes are present in the spleen but dsDNA specificity is disrupted due to expression of endogenous L chains. In a Rag-2-deficient background where co-expression of endogenous Ig is blocked, splenic B cells expressing only the anti-dsDNA transgene Ig are present, indicating that endogenous Ig expression is not required for bone marrow export. The anti-dsDNA B cells that persist are profoundly crippled in that they are unable to proliferate to lipopolysaccharide or anti-Ig stimulation. Furthermore, these anti- dsDNA Ig transgene B cells show a decreased lifespan relative to non- transgene BALB/c B cells. Persistence of anti-dsDNA B cells in the periphery of non-autoimmune mice raises the possibility that their appearance in the context of SLE is due to their reactivation by T cell help.   相似文献   
638.
按Bishop方法,在小鼠血液里诱导生成大量网织红细胞,然后提取网织红细胞。用激光衍射法测得小变形指数(DI)d和变形恢复过程(即松驰过程)中细胞变形恢复到最大值(DI)max半的时间t0.5(变形恢复半时间),将测得结果分别代入细胞膜的膜剪切弹性模量(E)公式和表面粘度(μm)公式,计算出网织红细胞和成熟红细胞膜的膜剪切弹性模量(E)和表面粘度(μm),并用荧光偏振法测量它们的膜流动性。发现网织红细胞与成熟红细胞的膜的剪切弹性模量(E)和表面粘度(μm)及膜的流动性有着明显的不同。这对研究由于贫血等原因造成的网织红细胞增多情况下,全血的微观流变特性有着重要的临床意义,对我们认识哺乳类网织红细胞的微观流变特性有重要理论意义及认识哺乳类动物网织红细胞向成熟红细胞转变的微观流变特性变化有着重要理论意义。  相似文献   
639.
Vitex doniana is traditionally used in Togo to treat various diseases including wounds. The aim of this work was to evaluate the efficiency of Vitex doniana on cutaneous wound healing. Wounds were induced in ICR mice divided into four groups as following: Group I received carbopol 974P NF empty gel, Groups II and III were treated topically with carbopol gel containing 2.5% and 5% of Vitex doniana extract. Group IV received Betadine® 10% as standard drug. The efficacy of treatment was evaluated by planimetry and histological analysis. We secondary used the gel containing Vitex doniana at 2.5% and the pure extract at 10 mg/ml on the model of ear edema induced by xylene. Skin toxicity test was performed with the gel containing Vitex doniana at 5% and the pure extract at 30 mg/ml. Vitex doniana at 5% and 2.5% provided better wound contraction (91.14% and 86.38%) at day 12 post-excision when compared to control (51.15%). The results of histological evaluation supported the outcome of excision wound model. Moreover Vitex doniana inhibited significantly edema induced by xylene when compared to control (p< 0.05). In skin toxicity test, no abnormal symptoms were developed over 14 day-time period. Vitex doniana inhibits the topical inflammation and accelerate cutaneous wound repair.  相似文献   
640.

Background  

Stromal cell-derived factor-1 (SDF1) and its major signaling receptor, CXCR4, were initially described in the immune system; however, they are also expressed in the nervous system, including the spinal cord. After spinal cord injury, the blood brain barrier is compromised, opening the way for chemokine signaling between these two systems. These experiments clarified prior contradictory findings on normal expression of SDF1 and CXCR4 as well as examined the resulting spinal cord responses resulting from this signaling.  相似文献   
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