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121.
122.
BACKGROUND & AIMS: Murine autoimmune gastritis, induced by day-3 thymectomy, is characterized by cellular infiltrates and circulating autoantibodies to gastric hydrogen/potassium adenosine triphosphatase. The aim of this study was to analyze the cellular infiltrates and cytokines in autoimmune gastritis. METHODS: Stomachs and blood samples from day-3 thymectomized BALB/c mice were obtained from 2 to 12 weeks after thymectomy for analysis. RESULTS: At 4 weeks, the gastritic infiltrates were composed of macrophages and CD4+ T cells, accompanied by major histocompatibility complex class II expression on gastric epithelial cells. Mucosal B cells, scant at 4 weeks, were abundant at 8 weeks, coincident with the peaking of autoantibodies to gastric hydrogen/potassium adenosine triphosphatase. CD8+ T cells increased marginally during the 12 weeks. Mononuclear cells from diseased stomachs transferred gastritis to nu/nu recipients. At 4 weeks, interleukins 2, 3, 5, 6, and 10; interferon gamma; tumor necrosis factor alpha; and granulocyte-macrophage colony-stimulating factor were detected in gastritic mucosa, but interleukin 4 was not. CONCLUSIONS: The early lesion of autoimmune gastritis is composed of macrophages and CD4+ T cells with major histocompatibility complex class II expression in gastric epithelial cells. Autoantibody production is a late event. Our results are consistent with a lesion mediated by CD4+ T cells producing a mix of Th1- and Th2-type cytokines. (Gastroenterology 1996 Jun;110(6):1791-802)  相似文献   
123.
Two new human myeloma cell lines have been established from a 36-year- old woman with refractory IgG kappa multiple myeloma in whom bilateral malignant pleural effusions developed. The malignant plasma cells from each effusion were set up in a liquid culture using an L-15 medium containing catalase, glutathione, selenous acid, ascorbic acid, insulin, transferrin, additional glutamine hydrocortisone, and 2- mercaptoethanol and designated as M-3 medium. Two IgG kappa cell lines, LB -831 and LB-832, were established and proved to be Epstein-Barr virus negative using the internal repeat sequence DNA probe. Characteristic plasma cell morphology was evident by light and electron microscopy. Immunotyping revealed an IgG kappa , B1+, B2-, Ia (HLA- DR)+, CALLA+ phenotype for each cell line as well as for the original pleural fluid and bone marrow myeloma cells. The supernatants also contained IgG kappa, beta 2 microglobulin, and large amounts of osteoclast-activating factor (indicating bone-resorbing activity). Cytogenetic analysis of the LB-831 cell line revealed a nearly triploid highly abnormal karyotype with numerous clonal chromosomal abnormalities involving chromosomes 1, 3, 5, 7, 13, and 15; several structurally abnormal marker chromosomes; and a putative homogeneously staining region on chromosome 7p at band p22. Analysis of the LB-832 cell line revealed several additional clonal abnormalities. These additional cytogenetic changes suggest that in vivo sequential clonal evolution occurred in this patient. Therefore, two new but related cell lines have been established, which should prove useful for further biological studies.  相似文献   
124.
Williams  DA; Lim  B; Spooncer  E; Longtine  J; Dexter  TM 《Blood》1988,71(6):1738-1743
A recombinant retrovirus (DHFR*-SVADA) in which human adenosine deaminase (ADA) cDNA is transcribed from an internal SV40 promoter was used to infect murine hematopoietic stem and progenitor cells. Human ADA enzyme was not expressed in infected primary murine pluripotent stem cell-derived spleen or progenitor colonies (CFU-GM, CFU-Mix, BFU- E). In contrast, human ADA enzyme activity was readily detected in progenitor colonies derived from immortalized multipotent factor- dependent cells. The level of human enzyme was near endogenous murine enzyme levels and was equivalent in undifferentiated stem cells and differentiated myeloid, erythroid, and mixed colonies. These results indicate that cellular properties other than the stage of differentiation are important in determining the expression of foreign sequences introduced by retroviruses. Cell lines that are immortalized but still capable of induced differentiation may contain factors that abrogate blocks to expression that are manifested in primary hematopoietic stem cells.  相似文献   
125.
A patient with Burkitt's lymphoma in complete remission received myeloablative consolidation treatment with superfractionated total body irradation (1,320 rad) and cyclophosphamide (200 mg/kg) followed by autologous transplantation of previously harvested and cryopreserved blood-derived hemopoietic stem cells. Seven successive leukaphereses were performed to yield a total of 55.2 X 10(9) mononuclear cells (MNC) comprising 15.1 X 10(6) CFU-GM or 4.34 X 10(6) CFU-GEMM. Following autologous blood stem cell transplantation (ABSCT), reconstitution of all cell lines occurred very rapidly, ie, 1,000 leucocytes per microL were reached after nine days, 500 granulocytes and 50,000 platelets per microL after ten days. B cells reached normal values around day 35 post- transplantation. CFU-GM first appeared in the circulating blood exhibiting an enormous overshoot. Some days later CFU-GM also appeared in the marrow. The kinetics and pattern of hemopoietic reconstitution after myeloablative treatment and ABSCT provide clear evidence that blood-derived hemopoietic stem cells are capable of completely restoring hemopoietic function in man. A possible reconstitutive advantage of blood over marrow-derived stem cells is discussed.  相似文献   
126.
对于大多数胃食管反流病 (GERD)病人而言 ,治疗的主要目的在于控制症状和防止复发。而伴有糜烂性食管炎者 ,其主要目标则为愈合糜烂和 /或防止并发症。目前发现 ,大多数GERD病人 ,不论其内镜表现如何 ,短时间内使用抑酸药后 ,症状在 6个月内复发。要维持原来的疗效 ,确保糜烂愈合 ,用最小剂量质子泵抑制剂 (PPI)作维持治疗已是公认的较理想方法。当然长期维持治疗的选择也应顾及病人意愿。如果症状发作不频繁 ,那么按需治疗是一个合理的处理方案。事实上 ,病人也仅在症状复发时才会正规、持续地服药。对这类病人 ,以PPI作为按…  相似文献   
127.
Scillian  JJ; McHugh  TM; Busch  MP; Tam  M; Fulwyler  MJ; Chien  DY; Vyas  GN 《Blood》1989,73(7):2041-2048
There is evidence that some human immunodeficiency virus (HIV)-infected individuals have prolonged periods of seronegativity. A flow cytometric immunoreactive bead (IRB) assay is described for quantitative, simultaneous, and early detection of antibodies to HIV. Polystyrene beads of four diameters, each size coated with a different HIV recombinant DNA-produced protein (p24, p31, gp41, or gp120), bound anti- HIV antibodies detected with fluorescent antiglobulin. The IRB assay was performed on a panel of blood donor samples, many giving consistently false-positive enzyme immunoassay (EIA) and indeterminant Western blot (WB) results. The IRB assay proved as sensitive and more specific than currently licensed EIA and WB tests. Results on serial samples from eight HIV-infected individuals indicated that quantitation of anti-p24 by IRB assay may be useful in monitoring disease progression. Sequential pre- and post-EIA seroconversion sera from 35 HIV-infected homosexual men were tested by the IRB assay using IgM- and IgG-specific fluorescent probes. All 35 cases were IRB assay positive for at least one rDNA-p either before (17 of 35, 49%) or at the time of EIA positivity. Eleven cases (31%) initially had only IgM anti-HIV, primarily to gp41 (17%). In two individuals, the IgM response was detected at least 18 months before EIA seroconversion. The IRB assay is a widely applicable analytic procedure, potentially useful in pretransfusion anti-HIV screening of blood.  相似文献   
128.
Seed  TM; Cullen  SM; Kaspar  LV; Tolle  DV; Fritz  TE 《Blood》1980,56(1):42-51
Aplastic anemia and myelogenous leukemia are prominent pathologic effects in beagles exposed to continuous, daily, low-dose gamma irradiation. In the present work, granulocyte reserves and related mobilization functions have been sequentially assessed by the endotoxin stress assay during the preclinical and clinical phases of these hemopoietic disorders. Characteristic patterns of granulocyte reserve mobilization are described that reflect given stages of pathologic progression. For radiation-induced leukemia, a five stage pattern has been proposed. In contrast, a simple pattern of progressive, time- dependent contraction of granulocyte reserves and mobilization capacity was noted in the development of terminal aplastic anemia. Early preclinical phases of radiation-induced leukemia appear to involve an extensive depletion of the granulocyte reserves ((phase I) during the first approximately 200 days of exposure followed by a partial renewal of the reserves and associated mobilization functions approximately 200 and 400 days (phase II). Sustained, subnormal granulocyte mobilizations (phase III) following endotoxin stress typify the responses of dogs during the intermediate phase, whereas late preclinical, preleukemic stages (phase IV) are characterized by a further expansion of the reserves and in the mobilization capacities, particularly of the less mature granulocytes. Such late alterations in the pattern of granulocyte mobilization, together with other noted cellular aberrancies in the peripheral blood and marrow, appear to indicate leukemia (phase V) onset.  相似文献   
129.
Hand mirror cells are a morphological configuration that are seen in immunologically stimulated lymphocytes and can be induced by antigen-- antibody complexes. Therefore, the bone marrow and peripheral blood plasma of two patients with acute lymphoblastic leukemia--hand mirror variant were evaluated for the presence of antigen--antibody complexes. Both patients had antigen--antibody complexes in the bone marrow plasma and not in the peripheral blood plasma as determined by double counter- current immunoelectrophoresis. The antigen moiety of these complexes appears immunologically related to components of the baboon endogenous virus (BaEV), and the antibody moiety also appears related to structural components of the BaEV. Bone marrow plasmas from patients without leukemia were evaluated for the presence of antigen--antibody complexes and found to be negative. The antigen--antibody complexes may account for the presence of hand mirror cells in the bone marrow of patients with acute lymphoblastic leukemia--hand mirror variant.  相似文献   
130.
Pettengell  R; Luft  T; Henschler  R; Hows  JM; Dexter  TM; Ryder  D; Testa  NG 《Blood》1994,84(11):3653-3659
Limiting-dilution analysis of long-term culture-initiating cells (LTCIC) is a quantitative method of estimating hematopoietic stem cell activity in clinical samples. We compared the numbers of LTCIC in bone marrow (BM), umbilical cord blood, and blood progenitor cells (obtained from patients with solid tumors at leukapheresis after mobilization with induction chemotherapy and filgrastim administration), using a two- stage long-term culture system and a limiting-dilution technique, scoring cobblestone areas of greater than 15 hematopoietic cells weekly for up to 8 weeks. Samples were obtained from 30 normal BMs, 20 human umbilical cords, and 32 leukapheresis products. Direct comparison of LTCIC in the three sources showed that the median proportions of cells generating hematopoietic foci from unfractionated mononuclear cells at 5 and 8 weeks, respectively, were 1:13,314 and 1:33,949 for BM, 1:12,506 and 1:34,546 for umbilical cord blood, and 1:10,302 and 1:12,891 for leukapheresis product. The estimated proportions of LTCIC from unfractionated mononuclear cells and CD34+ cells were similar in experiments with leukapheresis product. Leukapheresis product was superior to umbilical cord blood and cord blood to BM at 5 and 8 weeks of culture (P = .01). In two-stage long-term cultures, more colonies per flask and CD34+ cells were found in assays of leukapheresis product than in BM or umbilical cord blood cultures (P = .0005). Results obtained by this simplified limiting-dilution analysis correlated well with standard long-term cultures and can be used as a measure of the stem cell population. These data suggest that the incidence of putative stem cells in leukapheresis product and umbilical cord blood are at least comparable with that of BM.  相似文献   
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