Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.5.4.4 (adenosine deaminase)
 5,136 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Recent advances in the prevention of graft-versus-host disease through postthymic T-cell depletion have allowed the use of haploidentical bone marrow cells for immunologic reconstitution of severe combined immunodeficiency disease. We report a male infant with severe combined immunodeficiency (with normal adenosine deaminase) who developed two IgG kappa and one IgA lambda paraproteins 7 weeks following the administration of 1.4 X 10(9) maternal bone marrow cells depleted of postthymic T cells by soy lectin agglutination and sheep erythrocyte rosetting. Serum IgG rose from 128 to 820 mg/dl, and IgA from 0 to 2400 mg/dl, peaking at 10 weeks postgrafting. By 14 weeks posttransplantation T-cell numbers and function had risen to normal (all dividing T cells had the donor karyotype) and paraprotein concentrations began to decline. These observations strongly suggest that the later-appearing T cells regulated the B-cell clones from which the paraproteins were derived. Failure of such function to appear could account for the increased incidence of B-cell lymphomas in severe combined immunodeficiency.
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PMID:Appearance of multiple benign paraproteins during early engraftment of soy lectin T cell-depleted haploidentical bone marrow cells in severe combined immunodeficiency. 351 54

Activities of enzymes of the purine metabolic pathway, adenosine deaminase (ADA), purine nucleoside phosphorylase (PNP), and 5'-nucleotidase (5'-N), were investigated in the lymphoblasts of a patient with B-cell acute lymphoblastic leukemia. These lymphoblasts exhibited increased ADA activity and diminished activities of both PNP and 5'N' as compared to normal lymphocytes as well as non-T, non-B leukemia cells. This enzymatic pattern is identical to that which has been described in T-cell leukemic lymphoblasts and differs from that which has been observed in the malignant cells of undifferentiated B-cell lymphomas. These data suggest that there is biochemical heterogeneity within the spectrum of B-cell malignancies. Furthermore, inhibitors of ADA may be of use in those B-cell lymphoid neoplasms that exhibit increased ADA activity.
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PMID:Lymphoblast purine pathway enzymes in B-cell acute lymphoblastic leukemia. 626 97

Immunomorphologic methods were utilized to localize adenosine deaminase (ADA) in extrathymic benign lymphoid tissues and B-cell lymphomas. In reactive lymph nodes, tonsils and appendix, germinal centers displayed strong ADA-positive nuclear staining in small cleaved lymphocytes and weak nuclear and/or cytoplasmic staining in large lymphoid cells. A significant proportion of ADA-positive lymphocytes in the germinal centers were B-cells. The mantle zone of secondary follicles did not stain for ADA. The plasma cells in the medullary cords demonstrated mainly cytoplasmic staining. In the spleen, ADA-positive lymphocytes were located in the periarteriolar sheath and paratrabecular white pulp. In lymphoma B-cells, patterns of ADA staining were similar to those observed in normal B-lymphocytes of similar morphology. This study demonstrated that human normal and lymphoma B-lymphoid cells are heterogeneous with respect to ADA expression. This heterogeneity appears to be associated with differentiation and/or proliferation of B-lymphocytes.
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PMID:Immunohistochemical localization of adenosine deaminase in human benign extrathymic lymphoid tissues and B-cell lymphomas. 636 Mar 30