Biomedical subjects

M Tara

Publications and source records attributed to M Tara.

At least 19 recordsLinked to original sources

PubMed2001

HLA-A26, HLA-B4002, HLA-B4006, and HLA-B4801 alleles predispose to adult T cell leukemia: the limited recognition of HTLV type 1 tax peptide anchor motifs and epitopes to generate anti-HTLV type 1 tax CD8(+) cytotoxic T lymphocytes.

Genetic risk for adult T cell leukemia (ATL) has been implicated by ethnic and familial segregation of ATL patients from HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). To clarify the genetic risk for ATL, we characterized HLA class I alleles of ATL patients and analyzed the anchor motifs of HTLV-1 peptides binding to HLA class I molecules, using 291 lines of anti-HTLV-1 CD8(+) cytotoxic T lymphocytes (CTLs) generated in vitro with a total of 165 synthetic peptides for HTLV-1 Tax and Env proteins. Allele frequencies of HLA-A*26, B*4002, B*4006, and B*4801 were significantly higher in ATL patients than in HAM/TSP patients and asymptomatic HTLV-1 carriers in southern Japan. CD8(+) CTL analysis revealed the HTLV-1 Tax peptide sequence to completely lack anchor motifs of peptides binding to HLA-A*26,B*4002, and B*4006 molecules but to possess one anchor for HLA-B*4801, while the HTLV-1 Env peptide sequence had many anchor motifs for HLA-A*26, B*4002, B*4006, and B*4801 molecules. Most ATL patients featured heterozygous HLA class I alleles composed of HLA-A*26, B*4002, B*4006, and B*4801, with a lower number of HTLV-1 Tax peptide anchor motifs and epitopes generating anti-HTLV-1 Tax CD8(+) CTLs than individuals possessing other HLA alleles. The relationship between Tax epitope and ATL incidence was verified by the significantly decreased number of HTLV-1 Tax epitopes in ATL patients compared with asymptomatic HTLV-1 carriers (p < 0.01) as well as late onset ATL patients (p < 0.001). These results indicate that HLA-A*26, B*4002, B*4006, and B*4801 alleles predispose to ATL because of the limited recognition of HTLV-1 Tax peptide anchor motifs and epitopes capable of generating anti-HTLV-1 Tax CD8(+) CTLs.

Adult↗

PubMed2001

Existence of escape mutant in HTLV-I tax during the development of adult T-cell leukemia.

Although Tax protein is the main target of cytotoxic T lymphocyte (CTL) on human T-cell lymphotropic virus type I (HTLV-I)-infected cells, and Tax peptide 11 through 19 binding to HLA-A*02 has been shown to elicit a strong CTL response, there are patients with adult T-cell leukemia (ATL) bearing HLA-A*02. To explore whether there is genetic variation in HTLV-I tax that can escape CTL recognition during the development of ATL, the HTLV-I tax gene was sequenced in 55 patients with ATL, 61 patients with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), and 62 healthy carriers, and it was correlated with the presence of HLA-A*02. First, a premature stop codon in the 5' half of the tax gene that looses transactivation activity on the viral enhancer was observed in 3 patients with acute and 1 patient with chronic ATL. This stop codon was revealed to emerge after the viral transmission to the patient from sequence analysis in family members with ATL. Second, amino acid change in Tax peptide 11-19 was observed in 3 patients with ATL. CTL assays demonstrated that this altered Tax 11-19 peptide, observed in ATL patients with HLA-A*02, was not recognized by Tax 11-19-specific CTL. Two patients with ATL had large deletions in tax by sequencing, and 5 patients with ATL had deletions in HTLV-I by Southern blotting. These findings suggest that at some stage of ATL development, HTLV-I-infected cells that can escape the host immune system are selected and have a chance to accumulate genetic alterations for further malignant transformation, leading to acute ATL.

Codon, Terminator↗

PubMed2001

Improved outcome of adult T cell leukemia/lymphoma with allogeneic hematopoietic stem cell transplantation.

Adult T cell leukemia/lymphoma (ATL) is a poor prognosis T cell malignancy. In order to improve the outcome, we employed allogeneic stem cell transplantation (allo-SCT) for ATL in 10 patients, nine of whom were from HLA-identical siblings and one from an unrelated donor. Conditioning regimens varied among the patients except that all received total body irradiation. The patients tolerated the regimens well with mild, if any toxicity, and engraftment occurred in all cases. Median leukemia-free survival after allo-SCT was 17.5+ months (range 3.7-34.4+). Six of the 10 patients developed acute GVHD (one case each with grade I, III or IV, and three cases with grade II) and three patients developed extensive chronic GVHD. Four patients died after allo-SCT during the study period from either acute GVHD (grade IV), pneumonitis, gastrointestinal bleeding or renal insufficiency. Two of the 10 cases with no symptoms of GVHD relapsed with clinical ATL. These results strongly suggest that allo-SCT may improve the survival in ATL if a controlled degree of GVHD develops.

Adult↗

PubMed2001

A new G-CSF-supported combination chemotherapy, LSG15, for adult T-cell leukaemia-lymphoma: Japan Clinical Oncology Group Study 9303.

This phase II trial was performed to evaluate the efficacy of a new granulocyte colony-stimulating factor (G-CSF)-supported multi-agent chemotherapy protocol, LSG15, for aggressive adult T-cell leukaemia-lymphoma (ATL). Ninety-six previously untreated patients with aggressive ATL were enrolled and grouped as: acute type (58), lymphoma type (28) and unfavourable chronic type (10). Therapy consisted of seven cycles of VCAP (vincristine, cyclophosphamide, doxorubicin and prednisone), AMP (doxorubicin, ranimustine and prednisone) and VECP (vindesine, etoposide, carboplatin and prednisone). G-CSF was administered during the intervals between chemotherapy until neutrophil reconstitution was achieved. Eighty-one per cent of the 93 eligible patients responded [95% confidence interval (CI), 71.1-88.1%], with 33 patients obtaining complete response (35.5%) and 42 obtaining partial response (45.2%). The median survival time (MST) after registration was 13 months and the median follow-up duration of the 20 surviving patients was 4.2 years (range 2.8-5.6). Overall survival at 2 years was estimated to be 31.3% (95% CI, 22.0-40.5%). Grade 4 haematological toxicity of neutropenia and thrombocytopenia were observed in 65.3% and 52.6% of the patients respectively, but grade 4 non-haematological toxicity was observed in only one patient. LSG15 is feasible with mild non-haematological toxicity and improved the clinical outcome of ATL patients. MST and overall survival at 2 years were superior to those obtained by our previous trials.

Adult↗

PubMed2000

[Diphenylhydantoin-induced pure red cell aplasia after neurological surgery: report of two cases].

Pure red cell aplasia (PRCA) is characterized by severe anemia, reticulocytopenia, marked selective hypoplasia of the erythroid precursor cells in the bone marrow and normal peripheral leukocyte and platelet counts. We reported two cases of diphenylhydantoin (DPH)-induced PRCA after neurological surgery. They recovered completely with discontinuance of DPH therapy. Neurosurgeons should be aware of this side effect because most reported cases of PRCA have occurred about a few months after neurological surgery under general anaesthesia and DPH therapy.

Aged↗

PubMed1999

Allogenic bone marrow transplantation as a treatment for adult T-cell leukemia.

We performed allogenic bone marrow transplantation (BMT) in two adult T-cell leukemia (ATL) patients with HLA-identical siblings as donors. One patient, with acute ATL, relapsed 3 months after BMT. The other, with chronic ATL, has become free of disease over 18 months after the BMT from his human T-cell lymphotropic virus type 1 (HTLV-1)-negative sibling, and we were unable to detect HTLV-1 in the patient's peripheral blood. Based on our results and those of others, although there have been limited numbers of patients, BMT may represent the only potentially curative treatment for ATL, and the presence of graft-vs.-host disease tends to be related to good results, which suggests the possibility that graft-vs.-leukemia effects may play an important role in allogenic BMT for ATL.

Adult↗

PubMed1999

L-asparaginase induced complete remission in Epstein-Barr virus positive, multidrug resistant, cutaneous T-cell lymphoma.

A 30-year-old man was admitted to our hospital with subcutaneous tumors and a high fever. Based on biomicroscopic findings of the tumor, the patient was diagnosed as having diffuse, medium, well-differentiated malignant lymphoma. Immunochemical analysis showed that CD3, CD4, CD25, and TCR beta were positive, and in situ hybridization revealed Epstein-Barr virus-encoded small RNAs in the nuclei of the lymphoma cells. Despite the patient's resistance to multidrug therapy, complete remission was achieved using L-asparaginase. This case is unique because of its peculiar clinical course and a possible association with the Epstein-Barr virus. L-asparaginase may be an important treatment in other patients who exhibit some of these characteristics.

Adult↗

PubMed1998

Secondary monocytic leukemia with rearrangement of the MLL gene occurring during the course of adult T-cell leukemia.

In June 1994, a 39 year-old male with adult T-cell leukemia was admitted to our hospital and received combination chemotherapy including epipodophyllotoxin for approximately 1 year. The monocyte count increased gradually beginning in April 1995, accelerating to 100 x 10(9)/l in January 1996, when he was diagnosed with acute monocytic leukemia. Inv(11)(q21;q23) x 2 was recognized at that time by chromosome analysis, and rearrangement of the MLL gene was shown by Southern blot analysis. From the clinical course and subsequent examinations, the case was regarded as epipodophyllotoxin-related secondary leukemia. Recently, epipodophyllotoxin has frequently been used as a treatment agent for adult T-cell leukemia. It is valuable to note that secondary leukemia may follow even such an aggressive leukemia as adult T-cell leukemia.

Adult↗

PubMed1996

[Pneumocystis carinii pneumonia in a HTLV-I carrier with monoclonal proliferation of HTLV-I infected lymphocyte].

A 63-year-old woman had Pneumocystis carinii pneumonia without any apparent underlying disease such as cancers or HIV infection. Although she reacted positively for HTLV-I antibody, hematological findings and clinical symptoms did not suggest that this patient had an ATL. Southern blot analysis revealed that HTLV-I infected lymphocytes had already proliferated monoclonally. The development of overt ATL should be carefully monitored in this type of patient as Pneumocystis carinii infection in HTLV-I carriers were reported to be a predictive sign of ATL and the monoclonal integration of a HTLV-I genome in the lymphocytes in this patient also suggests the presence of neoplastic clone.

Blotting, Southern↗

PubMed1995

Human T-cell leukemia virus type-1 (HTLV-1) Tax is expressed at the same level in infected cells of HTLV-1-associated myelopathy or tropical spastic paraparesis patients as in asymptomatic carriers but at a lower level in adult T-cell leukemia cells.

Patients with human T-cell leukemia virus type-1 (HTLV-1)-associated myelopathy (HAM/TSP) generally harbor a much greater population of HTLV-1-infected T cells in peripheral blood mononuclear cells (PBMCs) than asymptomatic carriers. These cells are not malignant but frequently proliferate clonally. To investigate the possibility that higher expression of the viral activator Tax induces preferential proliferation of infected nonmalignant T cells in HAM/TSP patients, the expression of Tax mRNA in fresh PBMCs was analyzed by reverse transcriptase-mediated polymerase chain reaction. Total amount of Tax mRNA was higher in HAM/TSP patients than in carriers, but the expression level was almost the same as that in asymptomatic carriers when compared per infected cell. The expression levels in adult T-cell leukemia patients were significantly lower than those in HAM/TSP patients and asymptomatic carriers. These results indicate that tax gene is not expressed at a continuously high level in HAM/TSP patients who carry a high population of infected T cells, even in those with clonally proliferated infected T cells.

Base Sequence↗

PubMed1995

In vitro induction of cytotoxic T lymphocytes against HTLV-I-infected T-cells from adult T-cell leukemia patients, asymptomatic HTLV-I carriers and seronegative healthy donors.

We investigated an in vitro method to produce cytotoxic T lymphocytes (CTLs) against HTLV-I-infected T-cells using peripheral blood mononuclear cells (PBMC) of adult T-cell leukemia (ATL) patients, asymptomatic HTLV-I carriers (AC) and seronegative healthy donors. The PBMC were restimulated repeatedly for 4 weeks with HLA-matched HTLV-I-infected T-cells which had been pretreated at 56 degrees C for 30 min to inactivate infectious HTLV-I. The culture medium included 10-100 units/ml of recombinant lymphokines (rIL-1, rIL-2, rIL-4, rIL-6 and rIL-7) and 10% fetal calf serum in RPMI-1640 medium. The cytotoxic activity was measured against HLA-matched HTLV-I-infected T-cell lines after CD4+ or CD8+ cells were positively panned from the cultured PBMC. The PBMC of ATL, AC and healthy donors were able to produce either CD4+ or CD8+ CTLs against HTLV-I-related antigens (env, gag, p21x, p27rex and p40tax) as well as the antigen(s) of as-yet unknown specificity expressed on HTLV-I-infected T-cells. All the CTLs recognized the specific antigens in the context of either class I or class II HLA types. These results indicated that ATL patients, AC and healthy donors were immunocompetent to generate CTLs against HTLV-I-infected T-cells and probably against HTLV-I-transformed T-cells.

Adult↗

PubMed1995

Human T-cell lymphotropic virus type-I (HTLV-I)-associated myelopathy/tropical spastic paraparesis with acute type of adult T-cell leukemia.

We report a 47-year-old Japanese woman with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) combined with acute type adult T-cell leukemia (ATL). The susceptibility for HAM/TSP and acute type of ATL is hitherto explained by human leukocyte antigen (HLA) haplotype-linked immune responsiveness to HTLV-I. This patient's HLA (A24Cw1B54DR4DQ4/A24Cw3B51DR8DQ1) included a HAM-associated HLA haplotype. This suggests that HAM patients with HAM-associated HLA haplotype can also develop the acute type of ATL.

Adult↗

PubMed1994

Variant type of sialyl Lewis X antigen expressed on adult T cell leukemia cells is associated with skin involvement.

Expression of a variant type of sialyl Le(x) antigen defined by 2F3 monoclonal antibody on leukemia cells was studied in 15 adult T cell leukemia (ATL) patients. The expression of 2F3-defined sialyl Le(x) antigen on CD4+CD45+ cells, which is an ATL cell-rich population, was higher in patients with skin involvement (50.1 +/- 23.1% were positive) than in patients without skin involvement (18.1 +/- 12.5%) (P < 0.01). The other surface markers including classical sialyl Le(x) antigen defined by SNH3 or FH6 and LFA-1, VLA-4, CD4, CD25, ICAM-1, Leu8, and HLA-DR did not show a significant difference regardless of skin involvement. In the skin lesion of four patients that we could examine, infiltrating leukemia cells strongly expressed 2F3-defined sialyl Le(x) antigen. In one patient, we could also examine the expression of classical sialyl Le(x) antigen defined by SNH-3 and CSLEX-1, but this was almost negligible. Both skin and lymph node biopsy specimens were examined in two patients. Leukemia cells in the skin strongly expressed 2F3-defined sialyl Le(x) antigen, while its expression was almost negligible on the leukemia cells in the lymph node. These findings suggest that the expression of 2F3-defined sialyl Le(x) antigen on ATL cells is associated with skin involvement of ATL.

Adult↗

PubMed1994

HTLV-I messenger RNA is expressed in vivo in adult T-cell leukemia/lymphoma patients: an in situ hybridization study.

Adult T-cell leukemia/lymphoma (ATLL) is a malignancy involving peripheral blood, lymph nodes, skin and other organs. Human T-cell leukemia virus type I (HTLV-I) is etiologically associated with ATLL but cannot be detected by conventional methods in fresh samples of peripheral blood and skin taken from ATLL. The aim of this study was to investigate the feasibility of an in situ hybridization technique for detection of HTLV-I mRNA in atypical lymphoid cells of peripheral blood and skin lesions of patients with ATLL. We detected variable amounts of HTLV-I tax mRNA in the nuclei and cytoplasm of these cells in fresh peripheral blood samples and skin lesions from ATLL patients, and also in asymptomatic HTLV-I infected donors to a lesser extent. Out of 10 patients with ATLL, 7 showed strong positive in situ hybridization whereas the other 3 were only weakly positive. However, in the last 3 cases, the reaction became strongly positive after cells had been cultured for 24 hr. Furthermore, all 3 asymptomatic HTLV-I-infected donors exhibited a weakly positive response in their apparently mature lymphoid cells.

Adult↗

PubMed1993

[Clonal change of HTLV-1 infected lymphocytes before onset of adult T-cell leukemia/lymphoma].

A 73-year-old HTLV-1 infected male developed overt ATL following 3-years observation, and the clonality of HTLV-1 infected cells changed before overt ATL onset. 10 micrograms of DNA, extracted from mononuclear cells was digested with PstI, and the clonal proliferation of HTLV-1 infected cells was examined by Southern blotting with LTR probe. 4 bands were observed 3 years prior to ATL onset, and 2 different bands were detected 2 years and 6 months later. This suggests that in some ATL cases, the clonality of monoclonally proliferated HTLV-1 infected cells may be changeable before overt ATL onset.

Aged↗

PubMed1992

Urinary excretion of parathyroid hormone-related protein as a predictor of hypercalcemia in patients with adult T-cell leukemia.

Hypercalcemia with adult T-cell leukemia (ATL) is chiefly caused by an excessive production by tumor cells of parathyroid hormone-related protein (PTHrP). We have previously reported hypercalcemic patients with solid tumors to excrete a large amount of the C-terminal fragments of PTHrP (C-PTHrP) into their urine. To elucidate whether PTHrP production correlates with or predicts the development of hypercalcemia, we studied the urinary excretion of C-PTHrP in 36 ATL patients. The urinary excretion of C-PTHrP was in the normal range (< 0.40 nmol equivalent to PTHrP (109-141)/g creatinine) in HTLV-1-positive carriers (n 3), ATL patients in complete remission (n 2) and chronic type ATL patients (n 2). It was marginally increased in seven patients in partial remission, and gradually increased as the disease progressed. In 20 patients who died without or with hypercalcemia, it was increased to 1.98 +/- 0.69 (n 9) and 7.6 +/- 2.1 nmol/g creatinine (mean +/- SD, n 11, P < 0.01), respectively. Urinary C-PTHrP excretion was significantly correlated with serum calcium and LDH levels as well as with CD25-positive cells in the peripheral blood. In four patients whose urinary excretion had been serially determined, it increased prior to the development of hypercalcemia. The findings suggest the urinary excretion of C-PTHrP to be of use as a predictor of the development of hypercalcemia in ATL patients. In ATL patients whose urinary excretion of C-PTHrP is progressively increasing, the serum calcium concentration should be carefully monitored to prevent hypercalcemic crisis.

Adult↗

PubMed1991

[A study on the frequency of von Willebrand factor deficiency state].

In order to elucidate the prevalence of von Willebrand factor (vWF) deficiency state, we investigated plasma vWF levels among 343 patients with bleeding tendency, 465 patients without bleeding tendency and 704 random unrelated normals living in Kagoshima prefecture. The prevalence of symptomatic vWF deficiency state was at least 2.3 per 100,000 of the population, and that of asymptomatic one in healthy individuals was 1.3%. These results indicate that the overall incidence of vWF deficient state in general population would be considerably higher than that previously reported.

Adolescent↗

PubMed1991

[Plasma concentrations of plasminogen activator inhibitor 2 in patients with hematological malignancies and their clinical significance].

We investigated plasma levels of plasminogen activator inhibitor 2 (PAI-2) in 40 patients with hematological malignancies including acute leukemia, chronic leukemia, hemophagocytic histiocytosis (HH) and histiocytic sarcoma (HS). The plasma PAI-2 levels in the patients with mononuclear phagocyte system (MPS) proliferative disorders (M4, M5, and CMMoL on FAB classification, HH and HS) were all above the cut-off value in healthy subjects. In a patient of reactive HH, there was a close correlation between Plasma PAI-2 and serum ferritin levels during the clinical course. These results indicate that the increase of plasma PAI-2 would be a diagnostic indicator of MPS proliferative disorders.

Adult↗