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771.
Rh E/e genotyping by allele-specific primer amplification 总被引:1,自引:0,他引:1
Faas BH; Simsek S; Bleeker PM; Overbeeke MA; Cuijpers HT; von dem Borne AE; van der Schoot CE 《Blood》1995,85(3):829-832
It has been shown that the Rhesus (Rh) blood group antigens are encoded by two homologous genes: the Rh D gene and the Rh CcEe gene. The Rh CcEe gene encodes different peptides: the Rh C, c, E, and e polypeptides. Only one nucleotide difference has been found between the alleles encoding the Rh E and the Rh e antigen polypeptides. It is a C-- >G transition at nucleotide position 676, which leads to an amino acid substitution from proline to alanine in the Rh e-carrying polypeptide. Here we present an allele-specific primer amplification (ASPA) method to determine the Rh E and Rh e genotypes. In one polymerase chain reaction, the sense primer had a 3'-end nucleotide specific for the cytosine at position 676 of the Rh E allele. In another reaction, a sense primer was used with a 3'-end nucleotide specific for the guanine at position 676 of the Rh e allele and the Rh D gene, whereas the antisense primer had a 3'-end nucleotide specific for the adenine at position 787 of the Rh CcEe gene. We tested DNA samples from 158 normal donors (including non-Caucasian donors and donors with rare Rh phenotypes) in these assays. There was full concordance with the results of serologic Rh E/e phenotyping. Thus, we may conclude that the ASPA approach leads to a simple and reliable method to determine the Rh E/e genotype. This can be useful in Rh E/e genotyping of fetuses and/or in cases in which no red blood cells are available for serotyping. Moreover, our results confirm the proposed association between the cytosine/guanine polymorphism at position 676 and the Rh E/e phenotype. 相似文献
772.
The immune response to a murine myeloid leukemia (cell line C1498) was studied in vitro and in vivo. Natural killer (NK) cells and CD8+ cytotoxic T lymphocytes (CTL) were shown to lyse C1498 in vitro through the binding of leukocyte function antigen-1 (LFA-1) on effectors and intercellular adhesion molecule-1 (ICAM-1) and ICAM-2 on C1498 target cells. However, the ability of nonimmunized mice to resist an in vivo challenge of a low dose (10(4)) of C1498 was NK-cell, but not T-cell dependent. The failure of T cells to participate in the immune surveillance of a low leukemia burden appeared, in part, because of a lack of expansion of leukemia reactive CTL precursors (CTLp). Leukemia reactive CTLp frequency estimations in naive and leukemia bearing mice were not significantly different (range, 1:20,600 to 1:74,000) in contrast to immunized mice (range, 1:1,400 to 1:4,400). Leukemia reactive CTLp could be expanded to a level that could apparently mediate in vivo immune surveillance of 10(5) leukemia cells by injection of irradiated leukemia cells intraperitoneally (IP) or subcutaneously (SC), but not intravenously (IV). However, IV injection of 10(5) live leukemia cells engineered to secrete interleukin-2 (IL-2) resulted in systemic immunity mediated primarily by CD8+ T cells. We conclude that NK cells can mediate immune surveillance of a low leukemia burden. CD8+ CTL-mediated immune surveillance can eliminate a higher leukemia burden than NK cells, but requires T-cell help, which can be delivered by local IL-2. Both NK and CTL-mediated immune surveillance of C1498 murine myeloid leukemia is dependent on recognition through the LFA-1:ICAM adhesion pathway. 相似文献
773.
Plasma levels of the chemokines monocyte chemotactic proteins-1 and -2 are elevated in human sepsis 总被引:17,自引:1,他引:17
Because of their effects on monocytes, monocyte chemotactic proteins-1 and -2 (MCP-1 and MCP-2) may participate in the pathophysiology of sepsis. We measured circulating MCP-1 and MCP-2 levels in 42 septic patients having positive local or blood cultures. MCP-1 and MCP-2 levels were elevated in 24 (57%) and 25 (59%) of 42 septic patients, respectively, compared with healthy volunteers. Both patients with gram- positive and gram-negative infections had elevated MCP-1 plasma levels (P = .0001) and P < .0001), respectively; Mann-Whitney-U test), whereas patients with gram-positive infection, but not those with gram-negative infection, had increased MCP-2 plasma levels (P= .0182). No relative differences in MCP-1 and MCP-2 plasma levels were observed between several subgroups of patients (sepsis v septic shock; survivors v nonsurvivors), although levels of MCP-1 were the highest in patients with the more severe forms of sepsis, ie, those with shock or a lethal outcome. Serial observations showed that MCP-1 and MCP-2 plasma levels remained elevated for at least 48 hours. MCP-1 correlated weakly with interleukin-8 and MCP-2, the correlations for which were most pronounced in patients with septic shock. MCP-2 correlated with interleukin-8, and surprisingly, with the complement activation product C3a; these correlations further improved when analyzing patients with septic shock or when applying gram-positive infections. Thus, our results not only show increased MCP-1 and MCP-2 levels in patients with sepsis, but also suggest that the synthesis and release of MCP-1 and MCP-2 in sepsis are differently regulated in part. 相似文献
774.
Parker PM; Chao N; Nademanee A; O'Donnell MR; Schmidt GM; Snyder DS; Stein AS; Smith EP; Molina A; Stepan DE 《Blood》1995,86(9):3604-3609
Thalidomide has been reported to be an effective agent for treatment of chronic graft-versus-host disease (CGVHD). To determine the efficacy of this agent in patients with refractory CGVHD a total of 80 patients who failed to respond to prednisone (PSE) or PSE and cyclosporine (CSA) were treated with thalidomide. Sixteen patients (20%) had a sustained response, 9 with a complete remission and 7 with a partial response. Twenty-nine patients (36%) had thalidomide discontinued because of side effects, which included sedation, constipation, neuritis, skin rash, and neutropenia. Side effects were reversible with drug discontinuation except for mild residual neuritis in one case. Rashes and neutropenia have not previously been reported as thalidomide side effects when used for CGVHD treatment. We conclude thalidomide is immunosuppressive and active in the treatment of CGVHD. A high incidence of reversible side effects limited dose intensity and reduced the number of patients who could benefit from treatment. 相似文献
775.
776.