Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study reviews results of fetal liver transplantation in hematologic disorders including aplastic anemia, leukemia and thalassemia. One hundred and twenty two patients received transplants for aplastic anemia; engraftment was reported in 4 patients; graft-versus-host disease (GvHD) did not occur. Complete and partial responses were reported in one-half of patients, the majority of whom had no evidence of engraftment. Thirty-nine patients received transplants for leukemia. Transient engraftment was reported in 40% and two developed GvHD; survival extended to more than 2 years. The higher rate of engraftment in patients with leukemia suggests a role of pretransplant immune suppression. The risk of GvHD appears to be low despite complete HLA-mismatching. These data suggest a possible role for fetal liver transplantation in man. Future studies should probably be based on preclinical data obtained in large animal models.
Thymus 1987
PMID:Fetal liver transplantation in aplastic anemia and leukemia. 332 6

The number of TNC complexes and of stroma cell-thymocyte rosettes was examined during the preleukemic period in mice given MNU to induce leukemia. In parallel, numbers of the complexes were studied following administration of hydrocortisone one day before administering MNU, i.e. after the procedure which clearly inhibited manifestation of induced leukemias. Administration of MNU with or without hydrocortisone is followed by disappearance of TNC complexes and stroma cell-thymocyte rosettes followed by their regeneration between 2 and 6 weeks after MNU. Relative rates of regeneration were different in MNU treated versus MNU + hydrocortisone treated animals.
Thymus 1988
PMID:Murine thymic multicellular complexes during latency period after methylnitrosourea (MNU) injection. 336 28

A thymocyte specific growth peptide (TGP) has previously been purified from bovine thymus. In the present study TGP activity is demonstrated in the conditioned medium from a murine thymic leukemia cell line with prothymocyte phenotype, but is absent from media of cultured thymic epithelium. This murine TGP shows specificity for immature thymocytes and growth-stimulating kinetics identical to bovine TGP. Murine and bovine TGP show different chromatographic behaviour which may indicate biochemical differences. The results suggest that the immature thymocyte population includes both TGP-producing and TGP-responding cells. Our finding of TGP activity in fresh homogenates of normal mouse thymocytes supports this interpretation. We propose that TGP acts as an autocrine growth factor for rapidly cycling immature cortical thymocytes.
Thymus 1987
PMID:Autocrine growth stimulation of thymocyte precursors in the thymus. 359 Feb 74

Thymus, spleen, and bone marrow of 1-month-old neonatally Moloney murine leukemia virus-inoculated mice have been transferred to 400-R-irradiated syngeneic recipients of the opposite sex. The donor or recipient origin of T-cell lymphomas arising in the host animal was identified by the sex chromosome marker. Spleen and bone marrow of athymic BALB-nu/nu mice contain cells with the potential to develop into T-cell lymphomas upon transfer to thymus-bearing BALB/c recipients. Such lymphomas arise from at least two subsets of T-cells, one terminal deoxynucleotidyl transferase (TdT) positive and the other 20 alpha-hydroxysteroid dehydrogenase positive. The enzyme-negative precursor T-cells from the BALB-nu/nu spleen and bone marrow can thus mature to enzyme-positive cells and give rise to lymphoma in the thymus-bearing recipient. Preleukemic spleen and bone marrow, but not thymus, from CBA and BALB/c mice regularly contained cells with the potential to develop lymphoma. The subset of T-cell involved was influenced by the genotype since lymphomas arising after the transfer of CBA and BALB/c spleens were TdT positive and 20 alpha-hydroxysteroid dehydrogenase positive, respectively. In thymus-bearing mice, but not in nude mice, the transfer of preleukemic spleen cells gave lymphomas earlier than did transfer of bone marrow cells. This suggests that the more mature lymphoid cell population in the spleen of thymus-bearing mice may allow leukemic transformation to occur more rapidly than do the less mature cells in the bone marrow. In one-third of the cases, the virus produced by the preleukemic cells transferred induced new lymphomas involving recipient host cells. These de novo-induced lymphomas were all TdT positive. We suggest that leukemic transformation of TdT-positive cells may occur through a different mechanism than does transformation of cells bearing the 20 alpha-hydroxysteroid dehydrogenase marker.
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PMID:Influence of genotype and the organ of origin on the subtype of T-cell in Moloney lymphomas induced by transfer of preleukemic cells from athymic and thymus-bearing mice. 387 60

Two of the major molecular components of murine leukemia virus particles, the internal protein (p30) and the envelope glycoprotein (gp69/71) have been measured in the spleens of normal, 6- to 10-week-old mice of various inbred strains and crosses. Both proteins were detected in virtually all mice. Extracts of high leukemia, high murine leukemia virus strains (AKR, C58, PL) showed high levels of both proteins; extracts of other strains usually showed lower levels. Of particular interest, however, were the exceptions to these general observations: (1) Very little gp69/71 could be detected in spleens of BALB mice, and this trait was dominant in crosses with AKR and DBA/2, both of which express a high level of gp69/71. Thymus-deficient BALB/c-nu/nu (nude) mice, in contrast, showed a higher concentration of gp69/71 typical of other low leukemia strains, suggesting that the virtual absence of the protein in normal BALB/c mice may result from immunologic suppression. (2) With C57L, C57BL/10Sn, and C57BL/6 strains the concentration of p30 was lower, in some cases much lower, than would be expected from the concentration of gp69/71. (3) DBA/2 mice showed high levels of gp69/71, 10-fold greater than that of p30, whereas congenic DBA/2-Fv-1(b) mice showed the opposite pattern. (4) Mice of 129-G(IX) (-) strain showed no detectable levels of either p30 or gp69/71 proteins, although the congenic 129 (G(IX) (+)) showed appreciable levels of both. The absence of these proteins in 129-G(IX) (-) mice is a recessive trait, as F(1) hybrids with AKR and DBA/2 showed appropriate levels of both proteins. It is concluded that expression of viral p30 and gp69/71 proteins in mice is not coordinately linked and that expression is complex, being influenced by several genes, including Gv-1, H-2, Fv-1, and probably still others.
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PMID:Host control of endogenous murine leukemia virus gene expression: concentrations of viral proteins in high and low leukemia mouse strains. 437 31

The bone marrow-derived (B) lymphocyte can be identified by the presence of easily detectable surface immunoglobulin and a receptor for antigen-antibody-complement complexes (EAC'). Monocytes and macrophages also bear a receptor for EAC' and in addition possess a receptor for red cell-IgG complexes (EA). Thymus-derived (T) lymphocytes bear neither of these receptors. The cells of 15 patients with leukemia and 19 human lymphoblastoid cell lines were examined for the presence of the EAC' and EA receptors. Of the human leukemias studied, only the cells from the patients with chronic lymphatic leukemia (CLL) possess the EAC' receptor. The EA receptor could not be demonstrated on CLL cells; hence, CLL cells bear the lymphocyte EAC' receptor and by this criteria represent B lymphocytes. 12/19 of the cell lines studied could be classified as B lymphocytes by the presence of the EAC' receptor and absence of the EA receptor. 2/19 cell lines possessed both the EAC' and EA receptors and thus resemble the monocyte. 5/19 cell lines had no detectable receptor for EAC' or EA. The approach presented in this study for the classification of leukemias and cell lines as to their B lymphocyte, T lymphocyte, or monocyte origin may have useful diagnostic and therapeutic implications.
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PMID:Receptors for complement and immunoglobulin on human leukemic cells and human lymphoblastoid cell lines. 450 40

Thymus leukemia (TL) alloantigenic activity was solubilized by papain proteolytic digestion from intact RADA1 tumor cells. If the cells were labeled with amino acids and fucose, the TL alloantigen could be isolated as a doubly labeled glycoprotein fragment by indirect precipitation from the papain digest. This TL glycoprotein fragment was approximately the same mol wt as the papain-digested H-2.4 alloantigen fragment as judged by chromatography on Sephadex G-150 in sodium dodecyl sulfate. The carbohydrate chain of the TL glycoprotein obtained by exhaustive pronase digestion behaved as a glycopeptide of approximately 4,500 mol wt, as compared with the glycopeptide of the H-2.4 alloantigen that had a mol wt of about 3,500. Thus, the TL alloantigen can be solubilized by papain digestion as a glycoprotein fragment similar in mol wt to the H-2 alloantigen glycoprotein fragment. The carbohydrate chain of the TL glycoprotein is larger than the H-2 carbohydrate chain.
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PMID:Some biochemical properties of thymus leukemia antigens solubilized from cell membranes by papain digestion. 454 Jul 99

An H-2-loss variant line, lacking H-2(a) antigens, was obtained from an H-2(b)/H-2(a) (C57BL x A)F(1) transplanted leukemia by immunoselection. The TL phenotype of the unselected line was TL.1,2,3,4 and that of the variant TL.1,2,4, which is the phenotype of TL(+) leukemias of C57BL. This finding, and the observed quantitative alterations of antigens TL.1,2 and 4, indicate that the Tla (Thymus leukemia antigen) locus was functionally deleted together with the H-2 locus in the process of variant formation, despite absence of selection against cells carrying TL antigens. Representation of H-2 antigens of the remaining haplotype, H-2(b), was quantitatively unchanged.
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PMID:Implications of TL phenotype changes in an H-2-loss variant of a transplanted H-2b-H-2a leukemia. 526 63

Thymus and spleen grafts from neonatal C57BL mice were implanted beneath the kidney capsule of (A x C57BL) F(1) hybrids. At various intervals after implantation, the grafts were analyzed serologically. Cells of each graft were tested for the presence of cells of host origin, TL (thymus-leukemia) antigenicity, and sensitivity to the cytotoxic effect of guinea pig serum (GPS). Thymus grafts showed partial repopulation by host cells 11 days after grafting, and some grafts were completely repopulated by host cells 13 days after grafting. All thymus grafts were fully repopulated 18 days after grafting. With one exception, thymus grafts contained no significant number of TL-positive cells within 14 days after grafting. TL-positive cells appeared in thymus grafts examined 15 days after implantation, and their number increased up to the 18th day after implantation. Cells residing in thymus grafts remained sensitive to GPS throughout the period of observation. The acquisition of thymus-distinctive serological properties by host cells repopulating thymus grafts was similar in intact and in thymectomized recipients. Spleen grafts were completely repopulated by host cells as early as 8 days after grafting. The cells residing in spleen grafts remained TL-negative throughout the period of observation, and were refractory to the cytotoxic effect of GPS. It is thus apparent that, while both spleen and thymus grafts are invaded by TL-negative cells, only those entering the thymus acquire the antigen. The nature of the process by which the thymus endows thymus-distinctive properties on cells entering it is discussed.
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PMID:Serological analysis of thymus and spleen grafts. 565 21

The analysis of seven differentiation markers following incubation with the tumor promotor 12-O-tetradecanoylphorbol-13-acetate (TPA) was examined in the human leukemic T-cell line MOLT-3. Significant changes were observed in the activity of the markers terminal deoxynucleotidyl transferase (TdT). spontaneous proliferation and the ability of these cells to bind sheep erythrocytes. Levels of human thymus-leukemia-associated antigen (HThy-L) recently identified as a low molecular weight form of adenosine deaminase (ADA), were reduced by about 50%. No significant changes were observed in ecto-5'-nucleotidase [5'-NT) activities, in the proliferative response to PHA, or in the expression of IA-like antigens. These data and the time kinetics of the changes suggest that following incubation of these T-lymphoblasts with TPA there is a sequential loss of TdT, loss of the capacity for spontaneous proliferation, and the appearance of receptors for sheep erythrocytes. Subsequently there is a decrease in the level of HThy-L/ADA. This sequence appears to follow that proposed for prethymic precursor T-cell differentiation following activation with thymic epithelium.
Thymus 1981 Nov
PMID:Modulation of human T-cell differentiation markers by 12-O-tetradecanoylphorbol-13-acetate. 627 66


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