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1.
Key words  axillary - block  相似文献   
2.
M. E. Weksler  S. Bodine    J. Rommer 《Immunology》1974,26(2):281-290
The response of lymph node, bone marrow, splenic and thymic lymphocytes to phytohaemagglutinin and Pokeweed mitogen has been studied. Depletion of theta positive or recirculating lymphocytes abolished the response to phytohaemagglutinin but did not impair the response to Pokeweed mitogen. Lymphocytes from thymectomized or athymic `nude' mice respond poorly or not at all to phytohaemagglutinin or Pokeweed mitogen.

We conclude that the normal response to Pokeweed mitogen depends upon an intact thymus gland. This despite the fact that one population of Pokeweed mitogen-responsive cells are theta-negative bone marrow-derived cells. This conclusion is based upon: (1) the equal reactivity of theta-positive and theta-negative lymphocytes to Pokeweed mitogen as shown by the normal response to Pokeweed mitogen of anti-theta serum treated lymphoid populations and (2) the impaired response of lymphocytes from nude mice and of lymphocytes from thymectomized, irradiated and bone marrow reconstituted mice to Pokeweed mitogen.

  相似文献   
3.
The purpose of this study was to determine whether acetaminophen impairs the immune response to influenza vaccine. Influenza vaccine is an under-utilized preventive measure, partly because of the unfounded perception that fever and myalgias frequently follow vaccination. While acetaminophen may decrease these infrequent side effects, it may also alter the immune response to vaccination. We compare the effect of acetaminophen with placebo on the humoral immune response to the 1991-1992 commercially available influenza vaccine. We studied 60 healthy, elderly subjects from a geriatric clinic and 20 infirm, elderly subjects from a nursing home. The subjects were randomly assigned to receive placebo or acetaminophen (1,000 mg every 6 h) for 2 days. Acetaminophen did not depress or enhance the immune development of serum hemagglutination inhibition antibody to the three vaccine antigens. The systemic side effects of fever and myalgia were uncommon in both groups. The healthy elderly subjects mounted a significantly better immune response to the influenza virus A/Taiwan/1/86 (H1N1) vaccine strain than did the infirm elderly subjects (geometric mean titer, 115 versus 51; P = 0.003). The functional activity score obtained by using the chronic healthy evaluation component of the Acute Physiology and Chronic Health Evaluation system could be used to distinguish the healthy from the infirm elderly (scores of 1.27 versus 3.75, P < 0.001). Acetaminophen neither depressed nor enhanced the serum antibody response to the vaccine in the healthy and infirm elderly subjects studied.  相似文献   
4.
Long-term growth of antigen-specific human T cells requires, in addition to IL-2, periodic exposure to antigen and accessory cells. In certain cases, accessory cells are not available or their presence in culture is undesired. We have developed a method of growing and sustaining human T cell lines and clones in long-term tissue culture in the absence of specific antigen or accessory cells. The requirement for antigen and/or accessory cells could be replaced by a monoclonal antibody to the CD3 determinant of human T cells (OKT3) bound to the surface of plastic tissue culture wells. Autoreactive, alloreactive, and antigen-reactive T cell lines and clones were maintained in culture for 8-12 weeks without antigen or accessory cells. The antigen specificity of these T cells was maintained.  相似文献   
5.
Cellular basis for the age-associated increase in autoimmune reactions   总被引:1,自引:0,他引:1  
The mechanisms that lead to the increased expression of autoantibodies with age are poorly understood. We have studied the number, size, and density of spleen and peritoneal cells from young and old BALB/c and C57BL/6 mice as well as the frequency of clonal precursors for antibodies to mouse erythrocytes, thyroglobulin, and IgG in these lymphoid preparations. Old mice have a 6-fold increase in the number of resident peritoneal cells and a 2-fold increase in the absolute number of Ly1-bearing B cells in this population. Furthermore, old mice have twice as many large, low density splenic B cells as young mice. The frequencies of B cell clonal precursors for anti-BrMRBC and anti-thyroglobulin antibody-forming cells in old mice were 3-10 times greater than in young mice. In the same cultures, however, no increase in the frequencies of B cell clonal precursors for anti-IgG or anti-DNA antibody forming cells was detected in old compared to young mice. These findings and other data suggest that there are at least two families of B cell autoantibody precursors, one including anti-BrMRBC and anti-thyroglobulin autoantibodies, the other including anti-IgG and anti-DNA antibodies. Studies of the differential regulation of these two families of autoantibody precursors might contribute to a greater understanding of autoimmune phenomena in age and disease.  相似文献   
6.
Positive selection of T cells within the thymus gland leads to major histocompatibility complex (MHC)-restricted recognition of antigen by T lymphocytes. As the thymus gland involutes with age, altered MHC-restricted antigen recognition by T cells from elderly humans would be expected. We have tested this hypothesis by comparing the proliferative response of T cells and T cell clones from aged and young subjects to influenza determinants presented by autologous or allogeneic antigen-presenting cells (APC). Under conditions in which the allogeneic mixed lymphocyte reaction was minimal, T cells from six of seven aged donors but only one of seven young donors were stimulated by influenza vaccine presented by allogeneic APC. More importantly, one-half of the influenza-specific T cell clones derived from aged donors, but none of the clones derived from young donors, were activated by influenza vaccine presented by allogeneic APC. While 80% of the MHC-nonrestricted influenza-specific T cell clones expressed the gamma/delta T cell receptor, 20% of these clones expressed the alpha/beta T cell receptor. Thus, changes in MHC-restricted antigen recognition by T cells and in altered distribution of alpha/beta versus the gamma/delta T cell receptor bearing antigen-specific T cell clones occur with aging.  相似文献   
7.
The human {T:T act} AMLR was characterized in its relationship to the {T:Non-T} AMLR and its validity as a nonxenogeneic antigen induced response was extended. Human T cell lines, established from responding T cells in an autologous mixed lymphocyte reaction (MLR), were maintained in medium containing human serum and interleukin-2 (IL-2). These cells stimulated 3H-thymidine incorporation by autologous T cells and by autologous unfractionated blood mononuclear cells. Freshly activated T cells isolated from an autologous MLR stimulated autologous T cells to a lesser extent could be enhanced by adding IL-2. Twenty-five to 50% of T cells stimulated by activated T cells express the T8 determinant. In contrast, we have previously shown that less than 10% of T cells activated after 6 days in culture with non-T cells express the T8 determinant. The number of T8 bearing cells were increased significantly after 10 days in culture with non-T cells. This suggested that two types of reactions, the {T:Non-T} and {T:T act} AMLR, might occur in sequence when T cells and autologous non-T cells are cocultured: first, the activation of T4 cells by non-T cells, then by the activation of T8 cells by activated T4 cells. Finally, activated T cells can stimulate unfractionated autologous mononuclear cells without prior exposure to sheep erythrocytes or fetal calf serum.  相似文献   
8.
Summary: The age-associated changes in humoral Immunity affect the quality more than the quality of the antibody response. Changes in the quality of the antibody response with age include shifts in antibody specificities from foreign to autoantigens. in antibody isotypes from IgG to IgM, in antibody affinities from HIGH to low and in the antibody idiotypic repertoire. These changes can be traced to an impaired capacity of T cells to facilitate: (a) the maturation of B cells respect to isotype and affinity maturation in the periphery and (b) the development of a diverse B-cell repertoire from precursors within the bone marrow. In contrast, there is no evidence that the amount of immunoglobulin produced before or after immunization diminishes with age. Nonetheless, the impaired responses of the elderly to most vaccines and the greater susceptibility of the elderly to infections has fostered a view that immune senescence leads to a state of immune deficiency. However, it is more precise to describe immune senescence as leading to a state of immune dysregulation. The dysregulation of the humoral immunity is manifested by a shift from adaptive humoral Immunity, characterized by the production of a highly specific, high-affinity, IgG antibody response to foreign antigens, to a process of natural antibody-mediated immunity, dominated by low-affinity, polyreactive, IgM antibodies which react with autoantigens, Age-associated T-cell impairments appear to be the basis for the shift from adaptive to natural humoral immunity and their reversal should permit the restoration of an adaptive antibody response in the elderly.  相似文献   
9.
Continuous arteriovenous hemofiltration (CAVH) was successfully used in a 35-year-old woman, who had developed amniotic fluid embolism in the course of a premature labor and cesarean delivery. With CAVH, the pulmonary artery pressure decreased, the cardiac index rose, and the arterial oxygenation improved dramatically. This technique seems to be an important contribution to the management of amniotic fluid embolism.  相似文献   
10.
We have used a quantitative immunoblotting technique to analyze the repertoires of self-reactive antibodies in serum samples obtained from the same five healthy adults over a 25-year interval. The average age of the donors was 43 years at the time of the first serum sample and 69 years at the time of the second serum sample. The antibody repertoires of IgM and IgG were found to be strikingly similar among individuals in both early and late samples. Densitometric profiles of self-reactivity of serum IgM and of purified serum IgG remained unchanged over the 25-year interval. The total reactivity of serum IgG decreased significantly over the 25-year period. The observed stability of the natural self-reactive IgM and IgG antibody repertoires with aging supports the view that autoreactive B cells in the normal immune system are positively selected for reactivity with a limited set of immuno-dominant self-antigens throughout life.  相似文献   
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