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)

The development of immunocompetence during gestation depends upon the sequential differentiation of antigen-specific lymphoid cells in the context of epithelial inducing microenvironments. These early intrauterine events, which appear to be antigen-independent, include clonal diversification of idiotypes and isotypes as well as commitment to B or T cell lineages. The steps in cellular maturation can be traced through the use of lymphocyte differentiation markers. Cooperation among lymphoid subsets, as well as from nonlymphoid cells and possibly other cofactors, is necessary for the effective function of this array of lymphocytes. The rate of expansion of functional immunity may be limited as much by the ontogeny of these collaborating influences as by the intrinsic immaturity of the B and T cells themselves.
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PMID:Functional ontogeny of human lymphoid cells as a factor in maternal-fetal tolerance. 697 80

Blast cells in acute leukemia and lymphoma appear to be "frozen" at various stages of lymphoid cell differentiation. The enzymatic and antigenic phenotypes expressed by these cells often correspond to the gene products of their normal precursors. We have used various immunocytochemical and enzymatic techniques to identify membrane, nuclear, and cytoplasmic markers associated with the prolactin-dependent Nb2 lymphoma cell line. The Nb2 cells, whether stationary or in log-phase growth, did not express any surface immunoglobulin. However, 100% of the Nb2 cells bound both a monoclonal antibody raised to rat thymocyte W3/25-HLK, which specifically binds an antigenic determinant on rat T-helper cells, and second monoclonal antibody OX8-HL, which identifies rat nonhelper T-cells. Transmission electron microscopy showed no evidence of phagocytic vacuoles, and activity of the lysosomal enzyme muramidase was also absent. There was no evidence of the DNA polymerase enzyme terminal deoxynucleotidyl transferase. alpha-Naphthyl acetate esterase activity was indicated in about 50% of the Nb2 cells by a faint particulate cytoplasmic staining similar to that found in thymocytes. Rosette formation with guinea pig erythrocytes, a property of mature rat thymocytes, was not observed with Nb2 cells. The data suggest that the Nb2 tumor may have arisen from a thymocyte at an intermediate stage of differentiation. The presence of Thy-like alpha-naphthyl acetate esterase pattern and the binding of both W3/25-HLK and OX8-HL support the thymic origin and relative immaturity of these lymphoid cells. It is becoming increasingly apparent that a significant proportion of lymphomas and leukemias also originate in undifferentiated thymic cels.
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PMID:Thymic origin of the prolactin-dependent Nb2 lymphoma cell line. 704 17

Lymphoid system was studied morphologically in 61 infants aged under 1 year dying of sepsis, nonseptic inflammatory diseases and non-inflammatory processes. It was established that in sepsis generalization of the immune response and decompensation of the lymphoid system occurred in the development of which previous disorders of immune responsiveness (thymus pathology, immaturity of the lymphoid system of premature babies, respiratory viral infections) are of great importance. Unlike sepsis, local inflammatory processes are characterized predominantly by limited immune reaction and decompensation of lymphoid system has a local character. In babies of the first month of age reactions of the T-lymphocyte system predominate, in older babies those of the B-lymphocyte system.
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PMID:[Immunomorphologic aspects of sepsis in children under 1-year-old]. 708 93

Peanut (Arachis hypogaea) lectin (PNL) has been shown to agglutinate the 90% of cells from murine thymus which are supposed to be immature cortical thymocytes. Further studies on the numbers of thymocytes binding fluorescein isothiocyanate conjugated PNL (FITC-PNL) confirmed the large proportion of PNL binding cells. In other organs such as bone marrow, spleen and peripheral lymph nodes, smaller proportions of PNL positive cells have been recorded. PNL-positive cells outside the thymus have been reported to be either Thy 1-positive or null cells. It has also been suggested that PNL binding may be a marker for immaturity not only in relation to T lymphocytes but also amongst haematopoietic stem cells. Thus PNL binding as an aspect of lymphocyte differentiation is a matter of considerable interest. The current study describes the distribution of horseradish peroxidase-conjugated PNL (HRP-PNL) on frozen sections of mouse lymphoid organs. It seems that PNL binds to cells in germinal centres but not to those in some other areas containing activated lymphocytes. There is good correlation between the presence of PNL-binding germinal centres in frozen sections of lymphoid organs and the number of PNL-binding cells counted in cell suspensions from the same organs.
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PMID:Peanut lectin binding properties of germinal centres of mouse lymphoid tissue. 736 Feb 73

Prior studies of fluorescence anisotropy (polarization) with diphenylhexatriene in normal and malignant cell populations have shown differences which have been attributed to an altered membrane lipid composition in cancer. We studied fresh tumor cells from patients with diverse lymphoid neoplasms and found a discrete range of whole-cell fluorescence polarization values (P values) for each type of neoplasm. Following cell fractionation, however, the P values of isolated plasma membranes from malignant cells did not differ significantly from the values obtained with normal donor lymphocytes. Therefore, the altered whole-cell fluorescence polarization measurements in malignant cells are not likely to be due to gross lipid changes in the plasma membrane. Histochemical staining and cell fractionation revealed the presence of cytoplasmic lipid accumulations, and these had extremely low P values, which could account for the low P values of malignant cells. Complementary studies of lymphoid cell lines showed whole-cell fluorescence polarization measurements to be extremely sensitive to exogenous lipid supplements, but membrane values remained stable. We conclude that alterations in membrane lipid fluidity, as measured by the diphenylhexatriene probe, are not consistently found in lymphoid neoplasms and hence cannot presently be invoked to account for the malignant behavior of these cells. However, intracellular neutral lipid accumulation appears to be a common feature of the lymphoid neoplasm. The lipid alterations described could be characteristic of cell immaturity or proliferation rather than malignancy; nevertheless, they may convey unappreciated biological consequences.
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PMID:Role of cytoplasmic lipids in altering diphenylhexatriene fluorescence polarization in malignant cells. 744 90

In addition to their role in oxygen transport and ventilation, the lungs serve as an important defense function consisting of nonspecific and specific components. The nonspecific factors include aerodynamic filtration, mucociliary apparatus, bronchoalveolar fluid flow and lymphohematogenous drainage (anatomic systems) as well as phagocytosis and inflammation; the specific factors include B-cell immunity (IgG, A, M, D and E) and T-cell immunity (cell-mediated immunity). In the lungs, specialized lymphoid tissues in contact with epithelium (bronchus-associated lymphoid tissues; BALT) function in local antibody (secretory IgA) and cell-mediated immunity responses to foreign antigens. Based upon these considerations, a number of therapeutic interventions have been developed to enhance various components of lung defense. These include substances which enhance both nonspecific elements (leukocyte transfusion, plasma, nonspecific immunostimulants, e.g., immunoactive bacterial extracts) as well as specific elements (vaccines, intravenous gammaglobulin, plasma, interferons, cytokines). The need for further development and utilization of new immune interventions is underscored by the large number of infants and children who suffer from recurrent respiratory infections, who have either maturational immaturity (e.g. small for gestational age newborn), genetically determined (e.g. cystic fibrosis) or acquired defects (e.g. AIDS) of lung defense mechanisms. The emergence of antibiotic-resistant bacterial organisms, e.g. Streptococcus pneumoniae, poses an additional need for new immune interventions.
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PMID:Current concepts of immune interventions in children with respiratory diseases. 752 41

Terminal deoxynucleotidyl transferase (TdT) was initially considered as a marker of immature lymphoid cells, but many studies have since provided conclusive evidence for the existence of TdT+ cases of acute myeloid leukemia (AML). The reported incidence of TdT+ AML cases varies largely (from 0% to 55%, average of combined data of the literature 18%, children 19%, and adults 21%) suggesting interlaboratory differences in the types of AML examined, the sensitivity of the method used, and the percentage of positive blasts taken as cut-off value. Significantly higher frequencies of TdT+ AML were reported in studies employing immunocytochemical staining (alkaline phosphatase anti-alkaline phosphatase or immunoperoxidase) than in series using immunofluorescence microscopy or biochemical assays. Statistical analysis of various cut-off levels demonstrates an inverse correlation between cut-off point and incidence. The combined data show that TdT-positivity is more common in the immature cell types (M0, M1), with no correlation with age or sex. Except for contested suggestions of an association with t(6;9) and t(8;21), no clear relationship between karyotype and TdT status has been documented. Although an association between T-cell receptor or immunoglobulin gene rearrangements and expression of TdT in AML was postulated, subsequent studies could not demonstrate this correlation. There was no significant relationship with other immunophenotypic markers except for CD34 positivity suggesting that the TdT+ cells represent an immature population. The percentage of positive cells was usually lower in AML than in ALL; in most cases only a subpopulation of the AML cells was TdT+. Thus, TdT could be viewed as a marker of hematopoietic immaturity. In about one-half of the studies on adults, TdT expression was reported to indicate a poor prognosis; others did not find any prognostic difference between TdT+ and TdT- AML cases. No correlation between TdT-positivity and prognosis was found in childhood AML.
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PMID:Terminal deoxynucleotidyl transferase (TdT) expression in acute myeloid leukemia. 768 37

Clinical and cytologic characteristics were correlated to immunologic markers in 154 patients with newly diagnosed acute myeloid leukemia (AML). The panel of monoclonal antibodies (MoAbs) was selected to identify differentiation-associated antigens of both the myeloid and the lymphoid lineages (CD13, CD33, CD14, CD15, CD7, CD34, CD10, HLA-DR, CD19, CD2, CD5, TdT). The expression of multidrug resistance P-glycoprotein (P-170) was also evaluated in 117 patients. Differences in antigenic expression was observed among the various French-American-British (FAB) subgroups. HLA-DR was poorly expressed on the blasts of acute promyelocytic leukemia (M3), and was always found in FAB M5. CD34 was detectable in all M0 cases and only in one M3 (p < 0.001). Lymphoid-associated antigens were positive in 74 cases (48.1%). In particular, CD7 was found in 49 patients (31.8%), and TdT in 30 (21.3%), 15 samples displaying coexpression of these two antigens. The incidence of CD7+ cases was particularly elevated in M0 and M5 AML (p = 0.005). It significantly correlated with the expression of CD34, HLA-DR, P-170 (p < 0.001, p = 0.018 and p = 0.034 respectively), and with a leukocyte count > 50 x 10(9)/l (p = 0.038). Sixty-nine (59%) samples demonstrated P-170 positivity. Again, this phenotype was particularly expressed in the poorly differentiated forms (M5, M0 and M1) and showed significant correlation with the immaturity markers CD34, CD7 and HLA-DR (p = 0.013, p = 0.022 and p = 0.001, respectively). Expression of individual antigens correlated with prognosis. Refractoriness to first line therapy was associated with CD7 expression (p = 0.002) and P-170 (p = 0.001). The CD7 marker was also significantly associated with a very low overall survival (p < 0.001) and continuous complete remission (p < 0.001). CD14 expression also significantly predicted lower survival rates (p = 0.033). The combination (CD7+ CD14+) identified a subset of patients with a particularly adverse outcome. The prognostic value of CD7 expression, alone or in combination with other markers, was confirmed in multivariate analysis.
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PMID:Prognostic value of cell marker analysis in de novo acute myeloid leukemia. 790 93

Malnourished rats during suckling were orally immunized with cholera toxin (CT) after different periods of refeeding. Intestinal fluids, sera, and supernatant fluids from cultured mesenteric lymph node (MLN) cells were obtained after rats were given three doses of CT and analyzed by enzyme-linked immunosorbent assay (ELISA) to evaluate the specific antibody response. Serum-specific immunoglobulin G (IgG), IgA, and IgM were severely diminished in malnourished rats immunized with three doses of CT after 1 week of refeeding when compared with those of controls. Also, a decreased IgA ELISA titer of the intestinal fluids and abrogation of the capacity to neutralize the CT in the intestinal ligated loop test were found. When a booster was given at 113 days of age, the immune response continued to be affected in the serum and the intestinal fluid. The results from the analysis of the supernatant fluids from cultured MLN cells were coincident with those mentioned above. When one dose of CT was administered into Peyer's patches (PP) after 1 week of refeeding, an impaired immune response was found in the intestinal fluid of malnourished rats during suckling compared with that of controls. This result together with the analysis of supernatant from MLN and PP cell cultures suggests that antigen triggering in the PP was affected. When the refeeding period was extended to 30 days and then the first dose of CT was administered, the antibody immune responses in intestinal fluid serum and supernatant fluid approached control values. These observations reinforce the fact that the gut-associated lymphoid tissue immaturity of the rats when they received the first CT dose (at 28 days old) was the main reason for the decreased immune response observed in the experimental group.
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PMID:Deficient induction of the immune response to oral immunization with cholera toxin in malnourished rats during suckling. 792 75

Within the hematopoietic compartment, the murine Hlx homeobox gene is expressed in myeloid cells, most prominently in macrophages and granulocytes, and in immature B-lymphoid cells but not in erythroid, mast, or T-lymphoid cells. The level of Hlx mRNA increased with induced differentiation of the promyelocytic lines WEHI-3B and HL-60. To address its biologic action more directly, Hlx expression vectors were introduced into seven mouse hematopoietic cell lines representing several lineages. Although four lines did not tolerate stable Hlx expression, high-level expression was achieved in the early myeloid line FDC-P1 and in the immature T-cell lines Tikaut and WEHI-707. Overexpression of Hlx in FDC-P1 cells downregulated two markers of myeloid immaturity, Thy-1 and CD34, and also promoted changes in cellular and colony morphology, indicative of limited differentiation. Ectopic Hlx expression in the T-cell lines induced changes in cellular and colony morphology and adhesiveness, concomitant with decreased expression of adhesion molecules ICAM-1 (CD54) and Pgp-1 (CD44) and increased expression of heat-stable antigen. These results implicate Hlx in the control of myeloid maturation and the regulation of lymphoid adhesion processes.
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PMID:Enforced expression of Hlx homeobox gene prompts myeloid cell maturation and altered adherence properties of T cells. 809 5


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