Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0220723 (PCA)
 4,687 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

15 cases of HCL were studied with a panel of monoclonal antibodies against different leukocyte antigens. A B-cell phenotype different from that of B-CLL was observed (CD10-, CD19+, CD20+, CD21-, CD22+, CD37+, CD38-, FMC7+, LN1+, PCA-1+, BLy7+ and CD5-). As expected, CD11c and CD25 were positive and, in addition, a My7 and My9 positivity in varying degree was noted. 3 weeks of in vitro incubation did not significantly alter the phenotype. We conclude that HCL exhibits a unique phenotype among chronic B-cell leukemias, which is closer to the plasma cell stage of differentiation than that of B-CLL. The BLy7 monoclonal antibody seems to be a promising marker for HCL.
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PMID:Immunophenotype of hairy-cell leukemia. 222 30

The effect of mitogens and/or recombinant B-cell growth factors (M/GFs) on the in vitro growth of hairy cells was examined. Tumor cells were isolated from the spleens of four patients with hairy cell leukemia (HCL) by Ficoll-Hypaque sedimentation and E-rosetting. Enrichment for tumor cells was confirmed with intracytoplasmic immunoglobulin (Ig) staining, tartrate resistant acid phosphatase (TRAP) staining, and staining using monoclonal antibodies (MoAbs) directed at B, T, myeloid, and monocytoid antigens (Ags) in indirect immunofluorescence assays. Tumor cells were B1(CD20)+ B2(CD21)- B4(CD19)+ IL-2R(CD25)+ PCA-1 +/- TRAP+. HCLs neither synthesized DNA nor secreted Ig in response to culture with granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-1 alpha (IL-1 alpha), IL-1 beta, IL-2, IL-3, IL-4, IL-5, or IL-6. However, a proliferative response (stimulation index greater than or equal to 3.0) without Ig secretion was triggered in HCLs by mitogens or combinations of GFs. Specifically, DNA synthesis was induced at 3 days in three of four HCL samples cultured with Staphylococcus aureus Cowan A (SAC) or the combination of phorbol ester (TPA) and the calcium ionophore A 23187 (Ca2+); DNA synthesis was triggered later (day 7) by tumor necrosis factor (TNF) or by IL-4 and IL-5. In contrast, the fourth patient, a nonresponder to SAC or TPA/Ca2+, demonstrated increased DNA synthesis at day 3 when cocultured with IL-4 and IL-5. Both autoradiography and staining with antibromodeoxyuridine (BrdU) MoAb conjugated to fluorescein confirmed DNA synthesis by only a minority (5% to 23%) of tumor cells within each patient. Dual staining confirmed that responsive cells were both BrdU+ and TRAP+. DNA synthesis induced by TPA/Ca2+ was blocked specifically by anti-IL-6 Ab; in contrast, the HCL proliferative response to SAC, TNF, or IL-4 and IL-5 was not inhibited by anti-IL-6 Ab. alpha-Interferon inhibited the response to TPA/Ca2+, TNF, or IL-4 and IL-5 without any effect on response to SAC. Finally, peroxidase-antiperoxidase staining demonstrated that HCLs are induced by TPA/Ca2+, but not by SAC, to produce intracytoplasmic IL-6. These data demonstrate IL-4, IL-5, and IL-6 mediated DNA synthesis by HCLs in vitro and suggest a possible in vivo role for these growth factors in the pathophysiology of HCL.
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PMID:Response patterns of hairy cell leukemia to B-cell mitogens and growth factors. 224 29

Monocytoid B-cell lymphoma (MBCL) is a newly recognized B-cell neoplasm of uncertain histogenesis. The cytologic features of the neoplastic monocytoid B lymphocytes are virtually identical to those of hairy cell leukemia (HCL). As with HCL, progression of MBCL to a higher histologic grade is very unusual. However, whereas circulating leukemic cells are a characteristic feature of HCL, peripheral blood involvement has not been reported in MBCL. We recently studied a patient with MBCL of the spleen and axillary lymph nodes who developed peripheral blood involvement by MBCL cells. Unlike the cells of HCL, the circulating MBCL cells exhibited strong acid phosphatase activity that was tartrate sensitive. The leukemic cells had the antigenic phenotype IgM lambda, CD20+, CD11c+, CD5-, CD25(TAC)-, and PCA-1-. Immunogenetic studies of both lymph node and peripheral blood cells revealed identical immunoglobulin heavy-chain gene rearrangements. When compared with a series of HCL, the immunophenotype was similar except for the absence of PCA-1 and TAC. Progression of the MBCL to a large cell lymphoma, also expressing IgM lambda, was documented in an abdominal lymph node of this patient. Therefore, although rare, peripheral blood involvement by lymphoma cells may occur during the course of MBCL and should be distinguished from HCL with cytochemical and immunophenotypic studies. In addition, comparison of the clinical, pathologic, and immunologic features of MBCL with those of other low-grade B-cell neoplasms suggests that a close lineage relationship exists between MBCL and HCL.
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PMID:Monocytoid B-cell lymphoma: its evolution and relationship to other low-grade B-cell neoplasms. 278 62

The normal tissue counterpart of hairy cell leukemia is unknown. Because of the morphologic similarities of hairy cells to reactive and lymphomatous monocytoid cells, we compared the phenotypic characteristics of seven spleens involved by hairy cell leukemia with four reactive lymph nodes containing benign monocytoid B cells and three lymph nodes diagnosed as monocytoid B cell lymphoma. The hairy cells had a phenotype of surface Ig+, B1/Leu-14+, Leu-M5+, PCA-1+, Tac+, B2-, BA-1-, BA-2-, J5-, T10-, T11-, Leu-1-, Leu-2a-, Leu-3a-. The immunophenotype of both the reactive and neoplastic monocytoid B lymphocytes was virtually identical to the hairy cells. The major difference was that monocytoid B cells failed to react with anti-Tac and that PCA-1 expression was inconsistent. Despite these variances, the immunophenotypic similarities are remarkable, particularly the common expression of B1/Leu-14 and Leu-M5 (S-HCL3), and suggest a possible lineage relationship between hairy and monocytoid B cells.
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PMID:Hairy cells and monocytoid B lymphocytes: are they related? 311 7

The "in vitro" effect of IFN-alpha on the phenotypic profile of atypical cells from 5 hairy cell leukemia patients was investigated in a 72 hr culture assay. Cytochemical investigations revealed a dramatic decrease in the cytoplasmic content of acid phosphatase and tartrate resistant acid phosphatase in the absence of any apparent morphological modification. Flow cytometry showed that IFN-alpha markedly reduced the density of surface Ig without modifying the original isotype pattern. The expression of the receptor for the Fc fragment of IgG was also reduced. The class II MHC antigen recognized by the monoclonal antibody 12 remained essentially unchanged. Hairy cells were negative for OKT10 and PCA-1 and remained so after IFN-alpha incubation. Present data indicate that IFN-alpha is able to consistently and selectively affect membrane and cytoplasmic features of hairy cells in a short term period. The possibility is envisaged that these changes may be related to the therapeutic efficacy of IFN-alpha.
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PMID:Recombinant interferon alpha-2 modulates hairy cell phenotype "in vitro". 350 87

Monoclonal antibodies defining B-, T-, and myeloid-restricted cell surface antigens were used to characterize the lineage and state of differentiation of tumor cells isolated from 22 patients with hairy cell leukemia (HCL). These tumors were shown to be of B lineage because they strongly expressed the B cell-restricted antigens B1 and B4 and lacked T cell- and monocyte-restricted antigens. Moreover, the strong expression of the plasma cell-associated PCA-1 antigen on the majority of hairy cells suggested that these tumors correspond to later stages of B cell ontogeny. Dual fluorescence experiments further confirmed that HCL splenocytes that coexpressed B1 and PCA-1 demonstrated both the morphology and tartrate-resistant acid phosphatase positivity of hairy cells. The observation that some hairy cells either spontaneously produce immunoglobulin (Ig) or could be induced to proliferate and secrete Ig provides complementary support for the view that HCL is a pre-plasma cell tumor. However, staining of hairy cells with anti-IL2R1 monoclonal antibody, which is directed to the T cell growth factor receptor and/or with the anti-Mo1 reagent, directed to C3bi complement receptor, distinguish these cells from currently identified B cells.
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PMID:Hairy cell leukemia: a tumor of pre-plasma cells. 387 42

The effect of interleukin 1 (IL-1) was studied on leukemic cells from 12 patients with B cell chronic lymphoid leukemias including two cases of hairy cell leukemia (HCL), two cases of HCL-variant (HCL-V), one case of prolymphocytic leukemia (PLL), and seven cases of chronic lymphocytic leukemia (CLL). In most cases, IL-1 induced differentiation characterized by increments of sIg gamma+, sIg mu+ and PCA-1+ cells, and a decrement of CD5+ cells, and activation characterized by increments of CD23+ and HC2+ cells, but induced the proliferation of leukemic cells only in two HCL-V cases. Among these effects, increment of sIg+ cells was observed more frequently in non-CLL (4/5 cases) than in CLL (2/7 cases), and increments of sIg gamma+, CD23+ and PCA-1+ cells were induced more frequently by IL-1 beta than by IL-1 alpha. These results suggest that IL-1, especially IL-1 beta, plays a significant role in the differentiation and activation of leukemic cells, but has only a minor role as an extrinsic/leukemic cells in B cell chronic lymphoid leukemias, particularly those with more mature cells such as PLL and HCL.
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PMID:Interleukin 1 (IL-1 alpha and IL-1 beta) induces differentiation/activation of B cell chronic lymphoid leukemia cells. 805 79