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Adaptive differentiation of murine lymphocytes. IV. (Responder × Nonresponder) F(1) T cells can be taught to preferentially help nonresponder,rather than responder, B cells 下载免费PDF全文
Responses to the synthetic terpolymer L-glutamic acid, L-lysine, L-tyrosine (GLT) in the mouse are controlled by H-2-1inked Ir-GLTgenes. (Responder × nonresponder) F(1) hybrid mice, themselves phenotypic responders, can be primed with GLT to develop specific helper cells capable of interacting with 2,4-dinitrophenyl hapten (DNP)-primed F(1) B cells in response to DNP-GLT. Unlike the indiscriminant ability of F(1) helper T cells for conventional antigens (i.e. not Ir gene-controlled), which can help B cells of either parental type (as well as F(1)) equally well, GLT-primed F(1) T cells can only provide help under normal circumstances for B lymphocytes of responder parent origin; they are unable to communicate effectively with nonresponder parental B cells (1, and the present studies). The present studies reveal, however, that the induction of a parental cell-induced allogeneic effect during priming of F(1) mice to GLT actually dictates the direction of cooperating preference that will be displayed by such F(1) helper cells for B cells of one parental type or the other. Thus, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by parental BALB/c cells, develop into effective helpers for nonresponder A/J B cells, but fail to develop effective helpers for responder BALB/c B cells, and vice-versa. In contrast, F(1) T cells, primed to GLT under the influence of an allogeneic effect induced by either parental type, display significantly enhanced levels of helper activity for B cells derived from F(1) donors. These results are interpreted to reflect the existence of two interdependent events provoked by the allogeneic effect: one event augments the differentiation of GLT-specific helper T cells belonging to the subset corresponding to the opposite parental type; this would explain the development of increased helper activity provided to partner B cells of opposite parental type (as well as of F(1) origin). The second event, we postulate, involves the production of responses against the receptors which normally self-recognize native cell interaction determinants; this form of anti-idiotype response is restricted against self- recognizing receptors of the same parental type used for induction of the allogeneic effect, hence explaining diminished helper activity of such F(1) cells for partner B lymphocytes of corresponding parental type. 相似文献
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LR Brunham 《Clinical genetics》2009,75(1):39-40
C-terminal deletions in the ALAS2 gene lead to gain of function and cause X-linked dominant protoporphyria without anemia or iron overload
Whatley et al. (2008)
The American Journal of Human Genetics 83: 408–414 相似文献
Whatley et al. (2008)
The American Journal of Human Genetics 83: 408–414 相似文献
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背景和目的:国际5国脑血管病专家提出一种新的腩卒中亚型分类法,旨在介绍完整的"脑卒中表型"分类的新观念,该分类是包括脑卒中的病因和存在的所有病因相关的疾病,并将病因疾病按严重程度分成3级. 相似文献
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Rueda M Muñoz JF Arcos A Álvarez E Martínez S 《Journal of biopharmaceutical statistics》2011,21(3):526-554
Estimation of a proportion is commonly used in areas such as medicine, biopharmaceutical experiments, etc. Estimation of a proportion using auxiliary information has not been investigated in the literature. Ratio estimators of the population proportion and two-sided confidence intervals based upon auxiliary information are derived in this paper. Real data extracted from the Spanish National Health Survey are used to demonstrate the application of the proposed methods in the estimation of prevalences. Results derived from simulation studies show that proposed estimators are more efficient than the traditional estimator. Proposed confidence intervals outperform the alternative methods, especially in terms of interval width. A study on patients with hypertension is also considered to calculate various estimators and confidence intervals. 相似文献
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Autoimmune thyroid diseases (AITD) are the most common organ-specific autoimmune disorders affecting approximately 5% of the overall population. An aberrant interaction between abnormal thyrocytes, abnormal antigen-presenting cells and abnormal T cells forms the basis for the atypical autoimmune reaction targeting thyroid antigens. It was proposed that nongenetic (environmental and hormonal) factors play a crucial etiological role in AITD development, through altering immune-endocrine interactions. The most outstanding fact is that in genetically predisposed individuals, the disruption of these neuroendocrine-immune interactions by environmental factors results in thyroid autoimmune dysfunction. These interactions are able to incline the balance between Th1-Th2 immune response toward one side, resulting in a Th1-cell-mediated autoimmune reaction with thyrocyte destruction and hypothyroidism in Hashimoto's thyroiditis but to a hyperreactive Th2-mediated humoral response against TSH receptor with stimulatory antibodies leading to Graves' disease hyperthyroidism. In this review the main mechanisms involved are summarized. In this sense, the participation of stress-mediated activation of the sympathoadrenal system and hypothalamic-pituitary-adrenal axis, the hormonal changes occurring during pregnancy and postpartum acting on antigen-presenting cells and influencing, in this way, the balance of the immune status are shown to participate in AITD etiology. The possibility that altered levels of thyroid hormones during the course of the AITD may alter immune function is also discussed. 相似文献
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