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1.
Alcoholics admitted to the hospital solely for detoxication have been studied by flow cytometry to evaluate changes in the surface markers of peripheral blood leukocytes. As we have shown previously, such patients have an elevated percentage of CD8hl lymphocytes that are HLA DR+; we now demonstrate that they also have striking alterations in the quantitative relationships of the fine T-cell subsets. Both CD4+ and CD8hl lymphocytes have a sharply reduced percentage of the l -selectin+ CD45RA+ subset, increased percentages of the CD45RA-subsets, and several other fine subset alterations. The fine subset profile suggests, according to current correlations of phenotype and function, that both CD4+ suppressor inducer and CD4-dependent CD8+ suppressor effector cells are reduced, whereas other subsets, including CD8+ CTL or their precursors, are increased in relative percentages. Some of the phenotypic changes are reversible over the several days following withdrawal. In other results, the percentage of CD8hl lymphocytes expressing CD11b (β-integrin) is shown to be reciprocal with the percentage expressing l -selectin both in normals and alcoholics. However, the regression function of CD11b vs. l -selectin on CD8hl cells is different for the alcoholics than for the normals, indicating an abnormality in the regulation of the expression of these two adhesion markers. Taken together, this abnormality of adhesion molecules and the fine subset alterations previously described indicate widespread changes in the peripheral lymphocytes of currently drinking alcoholics. These changes suggest functional deficiencies that may include alterations of lymphocyte traffic and other adhesion-dependent functions, and a shift in the balance of regulatory interactions.  相似文献   
2.
Naturally occurring spectrin autoantibody was detected in normal human sera and in polyclonal blood grouping sera by the immunoblotting technique. The autoantibody seems to be IgG, stable, of high titre and low affinity. It was detected in all sera tested. Preparations of monoclonal antibodies directed against some blood group antigens and anti-A1 lectin reagent were devoid of spectrin autoantibody as expected. This autoantibody may be instrumental in clearing red cell membrane components from the circulation during haemolysis. Care must be exercised in studies designed to determine the association of some blood group antigens with the red cell membrane skeleton, when using polyclonal sera which contain spectrin autoantibodies in addition to the antibodies against the blood group antigen in question.  相似文献   
3.
4.
Sera from eleven patients with gonadal germ cell tumors were tested for alpha-fetoprotein (AFP) by counterelectrophoresis. Ovarian neoplasms containing either the endodermal sinus tumor (EST) or dysgerminoma and half of the testicular embryonal carcinomas elaborated the protein into the serum. The presence of AFP in the serum seemed to correlate with early metastasis or a fatal outcome. That the highest levels of AFP were found in cases of EST was in keeping with the theory that the tumor originates in cells of the yolk sac, a principal embryonic site of AFP synthesis.  相似文献   
5.
Retrograde transport of horseradish peroxidase injected iontophoretically into the nucleus of the optic tract of cats revealed that the direction-selective cells in this pretectal nucleus receive direct retinal projections from small retinal ganglion cells, the so-called gamma-cells. These cells from a horizontal band on the contralateral retina. Few labeled cells are found in the ipsilateral temporal retina. The input from the contralateral retina is 10 times more numerous than from the ipsilateral one. In both retinae the highest concentration of labeled cells is near the area centralis.  相似文献   
6.
The clinical manifestations of putative natural killer (NK) cell deficiency are not well-known but theoretically should include recurrent tumors and systemic viral infections. In this article, we discuss a patient with recurrent condylomata, vulvar and cervical carcinoma in situ, pulmonary infiltrates of unknown significance, and a hypercoagulable state. This patient has a dramatic persistent deficiency in her circulating "classic" NK cells (CD3-, CD16+, NKH1+) and a simultaneous persistent expansion of a normally minor lymphocyte cell subset (CD3+, CD4-, CD8-, NKH1+) that does not express the alpha beta heterodimer of the T cell receptor. T-lymphocyte function, as measured by mitogen and alloantigen responsiveness in vitro, was normal. The coexistence of this particular clinical complex with this unusual set of laboratory abnormalities tends to emphasize our meager understanding of the biologic role of NK cells. At the very least, these findings suggest that the clinical manifestations of NK cell deficiency need not be dominated by disseminated systemic viral infections and that perhaps there should be a higher index of suspicion for the scrutinization of NK cell function.  相似文献   
7.
In a previous study, we used transfectants expressing hybrid HLA-DR(beta 1*0403)/DR(beta 1*0701) chains to map sequences involved in polymorphic antibody binding epitopes on DR(alpha, beta 1*0403) or DR(alpha, beta 1*0701) molecules. Amino acids 1-40 of the beta 1 domain were found to make the major contributions to most of the antibody binding epitopes studied. To begin to localize sequences that contribute to polymorphic antibody epitopes on DR(alpha,beta 1*0101), DR(alpha,beta 1*1101) and DR(alpha,beta 3*0202) molecules, we used indirect immunofluorescence and flow cytometry to assess the binding of mAb to transfectants expressing hybrid DR(beta 1*0101)/DR(beta 1*1101) or DR(beta 1*1101)/DR(beta 3*0202) chains that divide the DR beta chain into three segments: amino acids 1-40, 41-97, and the beta 2 domain. The results indicate that amino acids 41-97 of the beta 1 domain on DR(beta 1*0101), DR(beta 1*1101), or DR(beta 3*0202) are critical in most of the epitopes, including those recognized by human antibodies MP4 and MP12, and mouse mAb GS88.2, I-LR1, 21r5, and 7.3.19.1, whereas amino acids 1-40 of DR(beta 1*1101) are critical in the epitope recognized by the MCS-7 mAb, and both segments 1-40 and 41-97 of DR(beta 1*1101) are important in the epitopes recognized by the I-LR2 and UL-52 mAbs. Based on these data and comparison of DR beta allelic protein sequences, the residues that may play critical roles in these antibody binding epitopes are predicted.  相似文献   
8.
Unmethylated CpG motifs found in bacterial DNA are potent activators of the innate and acquired immune systems, and rapidly induce the production of proinflammatory cytokines. We hypothesized that CpG DNA may also elicit the production of prostaglandins (PG), which are central lipid mediators of the immune and inflammatory response. To test our hypothesis, we stimulated murine spleen cells and RAW 264.7 murine macrophage cells with CpG DNA and assessed the effects on the PG synthesis pathway. Compared to control, DNA-containing CpG motifs induced >5-fold increase in PGE (2) production and rapidly up-regulated cyclooxygenase-2 (COX-2) at both the mRNA and protein level. CpG DNA was an extremely strong inducer of COX-2 as concentrations as low as 3 ng/ml induced COX-2 protein expression. The CpG DNA-induced PGE (2) down-regulated the immune response elicited by CpG. Blockade of PGE (2) production with selective COX-2 inhibitors or neutralizing anti-PGE (2) antibody markedly enhanced IFN-gamma secretion in vitro from CpG DNA-stimulated spleen cells. Moreover, selective COX-2 inhibition increased CpG DNA-induced IFN-gamma secretion in vivo. Inhibition of COX-2 also increased CpG DNA-induced lytic activity of NK cells. Taken together, these data indicate that DNA containing CpG motifs is a potent inducer of COX-2 and PGE (2) production. CpG-induced PG may subsequently down-regulate the immune and inflammatory responses elicited by the CpG DNA.  相似文献   
9.
This study was undertaken to resolve a positive mixed lymphocyte reaction between HLA-ABC identical, HLA-D different siblings. Three CD3+ CD4+ CD8- alloreactive T-lymphocyte clones, called 2/6, 7/1, and 7/2, were generated and extensively studied. Proliferation of 2/6 cells and 7/2 cells was blocked by anti-DQ monoclonal antibodies (mAbs), whereas anti-DR and DP were not effective. Stimulation of 7/1 cells was inhibited by anti-DR, but not by anti-DQ and DP mAbs. Testing on a well-characterized panel of reference B-lymphoblastoid cell lines showed that the DQ-specific clones 2/6 and 7/2 were able to proliferate upon stimulation by cells carrying the DQw7 and DQw8 but not the DQw9 subtype of DQw3. Clone 7/1 was proliferative towards cells expressing DRw11.1 but not towards DRw11.2- or DRw12-positive cells. Moreover, this clone detected determinants present on some DRw8 cells. Correlation of the reactivity of clone 7/1 with available sequence data suggests that amino acids 67, 71, and 86 of DR beta 1 molecules played a crucial role in forming the epitope recognized by this clone. In contrast, sharing of T-cell epitopes between DQw7 and DQw8 subtypes was not inferable from specific amino acid residues. The implication of these findings for T-cell allorecognition is discussed.  相似文献   
10.
Objective: To assess the relationship between tumor marker carcinoma antigen-125 levels in seminal plasma and serum and fertilization rates in an IVF program, using intracytoplasmic sperm injection (ICSI).

Design: A prospective study.

Setting: IVF Unit, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.

Patient(s): Twenty-five infertile patients with severe oligo-terato-asthenospermia syndrome and 25 fertile male donors.

Intervention(s): None.

Main Outcome Measure(s): Serum and seminal plasma carcinoma antigen-125 concentrations and fertilization rate per cycle.

Result(s): In the infertile group, the seminal plasma carcinoma antigen-125 levels ranged from 22.0 to 1,284.0 U/mL (mean level ± SD, 229.9 ± 274.2 U/mL). In the normospermic fertile male donors, the seminal plasma carcinoma antigen-125 concentrations ranged from 12.2 to 336.7 U/mL (mean level ± SD, 110.1 ± 91.6 U/mL). This difference was statistically significant. The mean ± SD ratio between the seminal plasma/serum carcinoma antigen−125 levels differed significantly between the infertile group (47.9 ± 61.3) and the fertile male donors (5.7 ± 3.5). In the infertile group, the ratio between the seminal plasma/serum carcinoma antigen-125 levels was found to be negatively correlated with the oocyte fertilization rate.

Conclusion(s): The ratio between carcinoma antigen−125 levels in the seminal plasma and serum may be an indirect marker for male infertility and fertilization rate in IVF treatment using ICSI.  相似文献   

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