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

Lymphopenia and monocytosis were found in one third of untreated myeloma patients but there was no correlation between the two. Half of the patients studied had an increase in medium basophilic lymphoid cells, and eight had a raised PAS score. Lymphocytes from the majority of untreated myeloma patients failed to respond to antigenic stimulation in vitro compared with age matched controls. Three patients were immunized but showed no increase in immunoblasts or rise in antibody titre. The findings strongly suggest that abnormal lymphocytes are present in the blood in myeloma. The failure of lymphocytes to respond to antigen provides an explanation for the lack of normal plasma cells and depressed antibody responses in myeloma.
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PMID:Lymphocyte abnormalities in myeloma. 19 12

The first symptoms of immunooseous dysplasia were growth retardation and myopia. Nephrotic syndrome was diagnosed at the age of 8 years. Skeletal roentgenograms showed spondyloepiphyseal dysplasia. In the renal biopsy there was nodular accumulations of PAS-positive hyaline material at the base of the granular stalks. There was lymphopenia with decreased CD4 and CD8 subpopulations. The condition of the patient gradually worsened until she died unexpectedly at 10 years with clinical symptoms of encephalitis. Autopsy documented cytomegaloviral pneumonia and advanced mesangioproliferative glomerulonephritis. In the spleen there was PAS-positive hyaline material massively infiltrating the walls of the central arterioles of the splenic follicles. There was marked depletion of lymphocytes in the spleen and in lymph nodes. The differential diagnosis of immunooseous dysplasia in the framework of spondyloepiphyseal dysplasia is discussed.
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PMID:Spondyloepiphyseal dysplasia with nephrotic syndrome (Schimke immunoosseous dysplasia). 820 84