Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

N-Methyl-N-nitrosourea (MNU) induces thymic lymphosarcoma in numerous mouse strains. We determined the neoplastic phenotype induced by MNU in 20 C57B1/6J mice. Eleven neoplasms were composed of cells that were CD4-CD8+, four neoplasms were composed of cells that were CD4+CD8+, two neoplasms were mixtures of CD4+CD8+ and CD4-CD8+ cells, and three neoplasms were made up of cells that expressed neither CD4 nor CD8. Expanded populations of CD4+CD8- cells were observed within individual neoplasms. Of 10 neoplasms that were further classified, all were composed of cells that were J11d+, indicating immaturity. CD3 expression was generally negative, while IL2R expression was variable in these neoplasms. These data from C57B1/6J mice, a strain with a low incidence of spontaneous (viral-associated) thymic lymphosarcoma, indicate that a continuous spectrum of immature phenotypes are produced by MNU. The finding that each immature cell population can be expanded in this model system differs from previous reports. Our data do confirm the general finding in AKR mice, a strain with a high incidence of spontaneous thymic lymphosarcoma, that cells with immature phenotypes, particularly CD4-CD8+J11d+, make up MNU-induced thymic lymphosarcomas.
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PMID:Flow cytometric analysis of thymic lymphosarcoma induced by N-methyl-N-nitrosourea in C57B1/6J mice. 154 44

Membrane markers on human lymphocytes separated from fetal liver and spleen were studied. Depending on the period of intrauterine development, a growing percentage of T- and B-lymphocytes (up to 16% and 45%, respectively) among spleen cells was seen, but in liver the number was low independent of the gestational age (T cells less than 10% and B cells less than 15%). The majority of early CD3+ spleen cells (21st-28th week) expressed TCR alpha beta but not TCR gamma delta, although a significant proportion of these cells was still lacking CD4, CD8, and CD5 differentiation antigens, suggesting their immaturity. Later spleen T cells (29th-36th week) expressed the phenotype as mature adult-type T cells (CD3+TCR alpha beta +CD4/8+CD5+). During ontogeny in fetal spleen, a growing number of B cells could be estimated without any changes in the proportion of subsets, expressing the different light and heavy chains. However, the proportion of CD5+ B cells decreased with gestational age. The results suggest that the functional immaturity of antenatal splenocytes could not be caused by dramatic phenotypical differences in comparison with adult-type splenic lymphocytes.
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PMID:Characterization of human lymphocytes separated from fetal liver and spleen at different stages of ontogeny. 191 78

HIV infection induces both immune deficiency and immune stimulation. Central to the pathology of HIV infection is reduction in the numbers and function of CD4 T cells. Impaired functions include decreased proliferation, IL-2 receptor expression and production of lymphokines (IL-2 and gamma interferon (IFN]. HIV infection stimulates B cells and CD8 T cells. This is seen relatively soon after HIV infection. Increased activation and immaturity are seen in both these cell groups. In vitro studies confirm HIV stimulation of these cells. Studies have been conducted on patients with AIDS and opportunistic infection (OI) or Kaposi's sarcoma (KS), with AIDS-related complex (ARC) or with persistent generalized lymphadenopathy (PGL), as well as on asymptomatic HIV-seropositive and -seronegative homosexually active men. The latter group has been followed at 6-month intervals for the past 2-3 years. Those who seroconverted (became HIV-infected) were studied to investigate early changes following HIV infection. To delineate the immunopathology of infection with HIV, serial testing of seropositive individuals was carried out to determine the rate of CD4-T-cell reduction. Lowered CD4-T-cell number and percentage and CD4/CD8 ratio correlate with the occurrence of AIDS and with survival after AIDS-KS diagnosis. Seropositive individuals, however, differed markedly in the rate of CD4-T-cell reduction; in some, no reduction in CD4 cells occurred over a two-year period of observation. We propose that, in individuals in which CD4 levels have reached a plateau, effective host resistance to further CD4 cytoreduction has occurred.
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PMID:Immune pathogenesis of AIDS and related syndromes. 295 95

The predominant cell type in the thymus expresses both of the function-associated T cell surface markers, CD4 and CD8, but CD4+ CD8+ cells are rare or absent outside the thymus. Double expression has therefore been assumed to be an indication of immaturity. However, recent reports have suggested that CD4+ CD8+ cells can appear in cultures of activated mature cells. We have therefore activated human peripheral blood lymphocytes and mouse spleen cells, lymph node cells, and cortisone-resistant thymocytes using a number of different stimulation regimes, and we have analyzed them at various times for CD4 and CD8 expression. In all cases, upon analysis of cultured cells by flow cytometry, CD4+ CD8+ cells were rare. A combination of microscopic analysis, cell sorting followed by microscopic analysis, and careful staining controls demonstrated that even when flow cytometry showed some CD4+ CD8+ cells, most of these were artifacts in the form of doublets or clumps of single positive cells or dead cells. Taking this into account, CD4+ CD8+ cells made up less than 1% in the mouse and less than 3% in the human T cell cultures at any time periods. We therefore found no evidence for the generation of large numbers of CD4+ CD8+ cells in cultures of mouse or human T cells.
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PMID:CD4+ CD8+ cells are rare among in vitro activated mouse or human T lymphocytes. 326 16

The T cell antigen receptor is likely to play a role in both positive and negative selection in the thymus. Three populations of thymocytes can be distinguished by the level of expression of the CD3-alpha/beta-chain heterodimer of the T cell antigen receptor (CD3/Ti alpha/beta) complex. Cells which fail to express these receptors or express low levels of receptors are contained in a population of thymocytes which express low levels of the CD5 antigen and are predominantly CD4+/CD8+. Thus, these cells appear to be relatively immature phenotypically. In contrast, the cells which express high levels of CD3/Ti alpha/beta co-express high levels of CD5 and are predominantly contained in the more mature single positive cells which express either CD4 or CD8. With the calcium-sensitive dye, Indo-1, and immunofluorescence, we demonstrated that, despite the relative phenotypic immaturity of cells which express low levels of CD3/Ti alpha/beta, these antigen receptors are able to mediate transmembrane signaling when stimulated with CD3 monoclonal antibodies. Although increases in calcium were observed in these CD3/Ti alpha/beta-low expressing cells in response to anti-CD3, no proliferative response was observed, even in the presence of phorbol myristate acetate. Proliferative responses were observed in the more mature cells which express high levels of CD3/Ti alpha/beta. These results suggest that, rather than a defect in the functional capability of the antigen receptor complex to mediate transmembrane signaling events, cellular responses to signals generated by the antigen receptor may differ at various stages of thymocyte development.
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PMID:Functional competency of T cell antigen receptors in human thymus. 350 Feb 9

The gene expression of myeloperoxidase (MPO), CD3 epsilon, and CD3 delta molecules, the gene rearrangement of T-cell receptor (TCR) delta, gamma, and beta and immunoglobulin heavy (IgH) chain, and the expression of cell-surface antigens were investigated in seven cases of CD7+ CD5- CD2- and four cases of CD7+ CD5+ CD2- acute lymphoblastic leukemia or lymphoblastic lymphoma (ALL/LBL) blasts, which were negative for cytochemical myeloperoxidase (cyMPO). More mature T-lineage blasts were also investigated in a comparative manner. In conclusion, the CD7+ CD5- CD2- blasts included four categories: undifferentiated blasts without lineage commitment, T-lineage blasts, T-/myeloid lineage blasts, and cyMPO-negative myeloblasts. The CD7+ CD5+ CD2- blasts included two categories; T-lineage and T-/myeloid lineage blasts. The 11 cases were of the germ-line gene (G) for TCR beta and IgH. Four cases were G for TCR delta and TCR gamma. The others were of the monoclonally rearranged gene (R) for TCR delta and G for TCR gamma or R for both TCR delta and TCR gamma. The expression or in vitro induction of CD13 and/or CD33 antigens correlated with the immaturity of these neoplastic T cells, since it was observed in all 11 CD7+ CD5- CD2- and CD7+ CD5+ CD2-, and some CD7+ CD5+ CD2+ (CD3- CD4- CD8-) cases, but not in CD3 +/- CD4+ CD8+ or CD3+ CD4+ CD8- cases. CD3 epsilon mRNA, but not CD3 delta mRNA, was detected in two CD7+ CD5- CD2- cases, while mRNA of neither of the two CD3 molecules was detected in the other tested CD7+ CD5- CD2- cases. In contrast, mRNA of both CD3 epsilon and CD3 delta were detected in all CD7+ CD5+ CD2- cases, indicating that CD7+ CD5- CD2- blasts at least belong to T-lineage. The blasts of two CD7+ CD5- CD2- cases with entire germ-line genes and without mRNA of the three molecules (MPO, CD3 epsilon, and CD3 delta) were regarded as being at an undifferentiated stage prior to their commitment to either T- or myeloid-lineage. The co-expression of the genes of MPO and CD3 epsilon in a CD7+ CD5- CD2- case MPO, CD3 epsilon, and CD3 delta in a CD7+ CD5+ CD2- case suggested the presence of some overlapping phase for T- and myeloid-lineage commitment during immature stages of differentiation. This helps understand the conversion of some T-ALL/LBL cases to acute myeloblastic leukemia (AML).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Lineage determination of CD7+ CD5- CD2- and CD7+ CD5+ CD2- lymphoblasts: studies on phenotype, genotype, and gene expression of myeloperoxidase, CD3 epsilon, and CD3 delta. 751 45

Three-color automated flow cytometry was carried out on peripheral blood CD4+ and CD8+ T-lymphocytes of 42 HIV-positive patients using tri-color anti-CD4 or anti-CD8, phycoerythrin-anti-CD38, and fluorescein-anti-HLA-DR, mAbs to elucidate further the T-cell activation hypothesis recently proposed to explain CD4+ T-cell abnormalities observed during HIV infection. CD4+ CD38+ T-cells constituted the major part of circulating CD4+ T-cells in HIV-infected patients and their HLA-DR molecule positivity increased as their disease progressed. The level of CD38 and HLA-DR expression on CD4+ T-cells was positively correlated to that of CD8+ T-cells and to the level of beta 2-microglobulin. Next, to determine whether CD38 expression was associated with a selective expansion or deletion of V beta gene-defined subsets, we compared the V beta gene frequencies between CD38+ and CD38- T-cells from HIV-infected CDC stage II patients using 13 mAbs specific to V beta families. While selective expansion of certain V beta families was observed in CD4+ and CD8+ T-cells the T-cell receptor V beta subset distribution was similar among CD38+ and CD38-, CD4+ and CD8+ T-cells, suggesting that CD38+ expression was either independent of an HIV-encoded antigen-driven process or rather indicative of T-cell immaturity. It is proposed that the phenotype of circulating CD4+ and CD8+ T-cells of HIV-infected patients is a feature of two different mechanisms: (i) an in vitro activation state responsible for increased DR expression and selective expansion of V beta gene-defined subsets, and (ii) T-cell immaturity due to an increased turnover of these cells and accounting for increased CD38 expression.
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PMID:During HIV infection, CD4+ CD38+ T-cells are the predominant circulating CD4+ subset whose HLA-DR positivity increases with disease progression and whose V beta repertoire is similar to that of CD4+ CD38- T-cells. 755 81

A reference range for lymphocyte populations, with particular emphasis on T lymphocyte subsets, was obtained for normal individuals covering age cohorts from birth through adulthood. This report confirms and extends findings from a developmental reference range published earlier (1). Absolute numbers of WBC, lymphocytes, and T, B, and NK subsets decline significantly during childhood. However, differences in the rate of decline of certain lymphocyte subsets leads to discordance between absolute numbers and percentages. Those lymphocyte subsets which decline less rapidly with age than the total lymphocyte count will show an increase in percentage, whereas those which decline more rapidly will show further declines in percentage values. T cell percentages were seen to increase over time whereas B cell percentages decline. Markers of immaturity such as CD45RA on CD4 cells and CD38 on CD8 cells declined in both percentages and absolute numbers. Activation markers, such as HLA-DR on CD8 cells and IL2-R on CD3 cells, increased in percentages with time but changed inconsistently in cell number from infancy to adulthood. These findings extend the lymphocyte references range to markers thought to be informative in various disease states, including HIV infection.
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PMID:Age-related changes in human blood lymphocyte subpopulations. II. Varying kinetics of percentage and absolute count measurements. 790 66

To study the efficacy of intravenous immunoglobulin in symptomatic infection with human immunodeficiency virus (HIV) we enrolled 35 patients with CD4 lymphocyte counts below 300/microliter in a randomized three-arm study. In addition to standard HIV treatment (e.g., zidovudine, aerosolized pentamidine), 13 patients were treated with 7.5 g and 11 with 40 g of a 7 S intravenous IgG preparation every 4 weeks over a period of 1 year. A control group of 11 patients remained on standard treatment. Clinical and laboratory parameters, including lymphocyte proliferation and in vitro immunoglobulin synthesis were evaluated prior to intravenous IgG administration. HIV-specific immunological abnormalities such as increased B-cell activation and B-cell immaturity were observed in all three study groups at the beginning of the study. Mitogen-induced lymphocyte proliferation was diminished. These disturbances were not influenced by intravenous IgG treatment. Further laboratory data and the course of the HIV infection (fever, antibiotic treatment, hospitalization, Candida and herpes simplex or cytomegalovirus infection) remained unchanged. Thus, our data with an observation period of 12 months do not support the use of intravenous IgG treatment in adult symptomatic HIV-infected patients with CD4 counts lower than 300/microliter.
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PMID:The use of intravenous immunoglobulins in symptomatic HIV infection. Results of a randomized study. 791 23

The purpose of this study was to phenotype and assay immunological function on cord blood from 70 samples. Immunophenotyping indicated similar numbers of CD2, 3, and 8-positive cells as in adult bone marrow. CD4-positive cells were increased and CD19, 20, and CD56-positive cells were decreased in numbers. Proliferative responses to nonspecific mitogens were lower in cord blood cells than in adult cells, as was NK activity and spontaneous secretion of IL-6 and TNF-alpha. This study confirms the relative immaturity of cord blood cells even when some functional assays appear normal.
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PMID:Immunological characteristics of umbilical cord blood cells: phenotypic and functional analysis. 792 84


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