Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024312 (lymphopenia)
 4,859 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In studies of the mouse thymus, lymphocyte mitoses are seen to be most frequent in the thymus cortex. There is evidence from thymic grafts that a hypothetical factor, thymopoietin, may stimulate mitosis of thymic lymphocytes. It is a factor which is postulated to act in conjunction with the PAS-positive mesenchymal reticular cells and epithelial reticular cells of the cortex. The thymus medulla is necessary for the integrity of thymic grafts, and may also elaborate a secretion for maintaining the cellular functions of the gland. Thymectomy has been used as a gauge for judging normal thymic function and results, in the mouse, in lymphopenia, degeneration of spleen and lymph nodes, delayed rejection of skin allografts, reduced ability of spleen cells to mount the graft versus host reaction, and reduced primary immune response to certain antigens. Correction of these deficiencies offers a means of evaluating various thymic extracts and grafts. Lymphocytosis-stimulating hormone (LSH) is known to maintain the peripheral lymphoid organs and cause lymphocytosis in the thymectomized animal. Diffusion chamber studies of thymic grafts also show restored lymphoid tissue by a cell-free factor (CIF). These two factors may be the same and probably represent the basis of the highly purified lymphocyte-stimulating proteins, LSHr and LSHh, which restore the L/P ratio in thymectomized animals and may stimulate lymphopoiesis in spleen and lymph nodes. LSHr, unlike LSHh, increases the total lymphocyte count. LSHr has been found to increase the humoral antibody response in neonatal mice both by the PFC technique and by direct hemolysis of sheep erythrocytes. Homeostatic thymic hormone (HTH) is a thymic extract of small molecular weight and contains nucleic acid. In the thymectomized guinea pig it has been found to maintain normal levels of lymphocytes in the blood, spleen and lymph nodes, to restore antibody titers to typhoid H antigen and to restore the toxic allergic reaction. Thymic humoral factor (THF) is of smaller molecular weight (less than 1,000) and probably is not a protein. It also enhances lymphoid proliferation in neonatally thymectomized mice. There is evidence that THF participates in humoral antibody formation because it stimulates PFC formation from neonatally thymectomized mice after inoculation with sheep erythrocytes. Its effects on cell-mediated immunity are seen from findings that injection of THF restores the ability of thymectomized mice to reject skin allografts. THF enables spleen cells from thymectomized or neonatal animals to mount the graft versus host reaction, and causes maturation of bone marrow cells and spleen or lymph node cells so that they can participate in the graft versus host reaction. It has been reported to stimulate lymphocytes to kill isogeneic tumor cells in vitro. Thymosin is protein extracted from the thymus. It has been found to alleviate leukopenia slightly and provide some improvement in lymphoid histology in thymectomized mice...
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PMID:Some endocrine aspects of the thymus gland. 6 31

Host defenses were evaluated in 70 healthy aged volunteers. Individuals who had diseases or who were taking medication known to affect the inflammatory and immune responses were excluded from the study. Volunteers were followed for 24 months to correlate their state of health with the evaluation of host defenses. Polymorphonuclear leukocyte function and the serum opsonic capacity for Escherichia coli and Staphylococcus aureus were normal. Assays of complement components and activity revealed unexplained elevations in native C3 and properdin, normal concentrations of factor B, normal conversion of C3 by inulin, and normal levels of hemolytic complement. The levels of IgG and IgA did not differ from levels noted in younger controls, but the concentration of IgM was decreased and that of IgE increased. The prevalence of autoantibodies was low. None of the volunteers were anergic, but lymphocyte responses to mitogens were depressed in three-day cultures. The number and percentages of E-rosette-forming cells and cells bearing surface IgD or IgM were normal. No lymphopenia was noted.
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PMID:Host defenses in the aged: evaluation of components of the inflammatory and immune responses. 35 76

The clinical details of a five-year-old boy with systemic lupus erythematosus and an inherited deficiency of the fourth component of complement (C4) have been reported elsewhere. In this study of his immune responses, immunization with bacteriophage phi X 174 demonstrated diminished antibody formation, abnormal immunologic memory and failure to switch from IgM to IgG during secondary response. We also noted persistent lymphopenia and reductions in peripheral-blood T lymphocytes, lymphocyte responses to mitogens and allogeneic cells and granulocyte chemotaxis. Kinetic studies revealed that delayed activation of the alternative pathway was corrected by purified C4 only if the classical pathway was not blocked. This finding is consistent with the concept that minute amounts of C3b provided through the classical pathway are necessary to prime the properdin system. Inability to activate the classical complement pathway, abnormal kinetics of alternative-pathway activation and depressed antibody responses to a T-cell-dependent antigen may predispose C4-deficient patients to viral infection or immune-complex formation.
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PMID:Immune response of a patient with deficiency of the fourth component of complement and systemic lupus erythematosus. 43 36

In patients with chronic calculous cholecystitis, the number of T-lymphocytes decreased, the number of B-lymphocytes and their ability to transform into the blasts in response to stimulation of the specific bacterial antigen increased, the synthesis of immunoglobulins intensified, a titre of the antibodies specific to microflora of the biliary mucosa grew, the levels of complement, lysozyme and properdin decreased, the bacterial activity of blood serum was suppressed. It is necessary to correct these disorders in the process of preoperative preparation of the patients.
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PMID:[Disordered immunologic reactivity in patients with chronic calculous cholecystitis]. 259 28