Mitsutoshi Tara

HLA-A*26, HLA-B*4002, HLA-B*4006, and HLA-B*4801 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.

Deoxycoformycin-containing combination chemotherapy for adult T-cell leukemia-lymphoma: Japan Clinical Oncology Group Study (JCOG9109).

Aggressive adult T-cell leukemia-lymphoma (ATL) generally has a very poor prognosis. Deoxycoformycin (DCF, pentostatin), an inhibitor of adenosine deaminase, has shown promising therapeutic efficacy for ATL. To develop a new effective therapy against aggressive ATI., we carried out a multicenter phase II study of DCF-containing combination chemotherapy. Sixty-two previously untreated patients with ATL (34, 21, and 7 patients with diseases of the acute, lymphoma, and unfavorable chronic types, respectively) were enrolled, but 2 were ineligible because they were judged to be favorable chronic types. A regimen of 1 mg/m2 vincristine intravenously on days 1 and 8, 40 mg/m2 doxorubicin intravenously on day 1,100 mg/m2 etoposide intravenously on days 1 through 3, 40 mg/m2 prednisolone orally on days 1 and 2, and 5 mg/m2 DCF intravenously on days 8,15, and 22 was administered every 28 days for 10 cycles unless disease progression or toxic complications occurred. Fifty-two percent of 60 eligible patients responded (95% confidence interval [CI], 38%-65%), with 17 patients (28%) achieving a complete response (CR) (95% CI, 17%-41%) and 14 achieving a partial response. The CR rate was inferior to those of both the previous Japan Clinical Oncology Group (JCOG) study (JCOG8701, 43%), a 9-drug combination chemotherapy of the second generation, and the subsequent JCOG9303 study (35%), a granulocyte colony-stimulating factor-supported, dose-intensified, 9-drug regimen. The median survival time of the 60 eligible patients in JCOG9109 was 7.4 months, and the estimated 2-year survival rate was 15.5%; these results were identical with those of JCOG8701 but inferior to those of JCOG9303. Grade 4 neutropenia and infection of grade 3 or greater were frequent (67% and 22%, respectively), and treatment-related death was observed in 4 patients (7%), scpticcmia in 2, and cytomcgalovirus pneumonia in 2. We conclude that DCF-containing combination chemotherapy is not a promising regimen against aggressive ATL.

L-Asparaginase-Based Induction Therapy for Advanced Extranodal NK/T-Cell Lymphoma

We describe treatment of a patient with advanced extranodal NK/T-cell lymphoma, nasal type, with multiple subcutaneous lesions and hemophagocytic syndrome. Considering the projected poor outcome of conventional treatments, we designed an L-asparaginase-based induction therapy. L-asparaginase (4000 units/day, day 1 to day 7) combined with vincristine (1 mg, day 1) and prednisolone (100 mg/day, day 1 to day 5) was administered by intravenous infusion every 3 weeks. Within a week after treatment was started, excellent response was observed. Because of an allergic reaction to L-asparaginase, 6 courses of CHOP (adriamycin, cyclophosphamide, vincristine and prednisolone) therapy were administered as consolidation after 4 courses of L-asparaginase. The lymphoma was controlled with complete remission lasting longer than 2 years without additional treatment. These results and related reports may contribute to greater therapeutic efficacy against at least some cases of extranodal NK/T-cell lymphoma and other related diseases. Further evaluations based on clinical study are expected to clarify these results.Int J Hematol. 2003;78:248-250.

Japan Clinical Oncology Group (JCOG) prognostic index and characterization of long-term survivors of aggressive adult T-cell leukaemia-lymphoma (JCOG0902A)

This study evaluated the clinical features of 276 patients with aggressive adult T‐cell leukaemia‐lymphoma (ATL) in 3 Japan Clinical Oncology Group (JCOG) trials. We assessed the long‐term survivors who survived >5 years and constructed a prognostic index (PI), named the JCOG‐PI, based on covariates obtained by Cox regression analysis. The median survival time (MST) of the entire cohort was 11 months. In 37 patients who survived >5 years, no disease‐related deaths in 10 patients with lymphoma‐type were observed in contrast to the 10 ATL‐related deaths in other types. In multivariate analysis of 193 patients, the JCOG‐PI based on corrected calcium levels and performance status identified moderate and high risk groups with an MST of 14 and 8 months respectively (hazard ratio, 1·926). The JCOG‐PI was reproducible in an external validation. Patients with lymphoma‐type who survived >5 years might have been cured. The JCOG‐PI is valuable for identifying patients with extremely poor prognosis and will be useful for the design of future trials combining new drugs or investigational treatment strategies.

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 56deg;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.

HTLV-I viral escape and host genetic changes in the development of adult T cell leukemia.

In the pathogenesis of adult T cell leukemia (ATL), an oncogenetic role of the human T cell lymphotropic virus type I (HTLV‐I) Tax protein, viral escape from the host immune system, and host genetic changes have been proposed as contributory factors. We examined the premature stop codons in tax gene as one of the mutations that may lead to escape of HTLV‐I from the cytotoxic T lymphocyte (CTL) response in HTLV‐I carriers, to test whether a putative CTL escape mutant can emerge in the early stage of ATL development and whether HTLV‐I infected cells with such a mutation can proliferate subsequently. We also examined deletion of cyclin‐dependent kinase inhibitor 4 (INK4) genes and mutation of p53 gene in combination with changes in the HTLV‐I genome in acute type ATL to test whether host genetic changes promoted the malignant transformation of ATL cells that carry putative CTL escape mutations. The premature stop codon in tax gene existed in many non‐ATL HTLV‐I carriers as a minor population but not in the commonest HTLV‐I sequence of the individual. This minor population with a premature stop codon did not expand subsequently in 3 asymptomatic carriers tested. There were cases who had a mutation or deletion in HTLV‐I who also have either deletion of INK4 genes or mutation in p53 gene. Our findings suggest that CTL escape mutation can occur at an early stage of ATL development, and that certain host genetic changes favor the development of the aggressive form of ATL.

Killer cell immunoglobulin-like receptor/3DL2 expression in adult T-cell leukaemia

a major advantage over the ristocetin-induced platelet aggregation mixing studies and the cryoprecipitate challenge. Most importantly, the referral of DNA samples to regional reference centres is far more feasible compared with fresh whole blood samples required for phenotypic testing. We have more experience with the genetic approach. Our methodology involves DNA extraction from whole blood, polymerase chain reaction amplification of the entire coding sequence of GPIBA followed by direct sequencing. While we agree that the interpretation of direct DNA sequencing is not without errors, we believe the likelihood of error is negligible when molecular cloning of the amplified material is performed. We are interested in performing molecular testing of additional type 2B VWD/PT-VWD patients. We believe that the question of this differential diagnosis merits a larger scale international study to heighten awareness of the diagnostic question, is PT-VWD truly rare or under diagnosed among type 2B VWD cases? We have recently received funds to initiate this survey and encourage the international haemostasis community to participate in this project. We hope that this study will add significantly to the clinical/molecular awareness of PT-VWD and will address a long recognised problem of the discrimination between the non-identical twins.

Adult T-cell leukemia predominantly involving exocrine glands.

Abstract:  Objectives: We describe a rare case of adult T‐cell leukemia (ATL) presenting with dry mouth and swelling of bilateral parotid and submandibular glands. The unusual involvement of these exocrine glands by malignant cells prompted us to conduct a detail characterization of these infiltrating and circulating leukemic T cells, which may provide insight to the pathogenesis of exocrine involvement in ATL. Methods: Immunophenotyping of peripheral ATL cells and microscopic examinations of various organs prepared by autopsy were performed. Analysis of the repertoire of T‐cell receptor (TCR) of parotid gland‐infiltrating ATL cells using molecular and immunohistochemical examinations were also performed. Results: Microscopic examinations of various organs prepared by autopsy revealed the predominant and specific exocrine gland infiltration of ATL cells. Reverse transcription‐polymerase chain reaction (RT‐PCR) followed by both TCR spectratyping and complementary determining region (CDR)‐3 sequencing analysis of TCR Vβ of parotid gland‐infiltrating T cells revealed a relatively restricted but not single usage of TCR Vβ. Immunohistochemical analyses of parotid gland specimens detected only a small number of TCR Vαβ‐positive cells in parotid gland‐infiltrating ATL cells. Conclusions: The predominant infiltration of ATL cells in exocrine glands implied that these T cells recognized exocrine gland‐specific antigen. However, the absence of both TCR Vβ mRNA transcripts and TCR Vαβ protein expression in most ATL cells suggested that antigen recognition via TCR may not have played a major role in adhesion and subsequent infiltration into the exocrine glands in this patient. These results provide important background information to further elucidate the pathogenesis of exocrine gland‐specific inflammation.

Neuro-immunological complications of retroviruses other than the HIV

Summary The aim of this review is to introduce and adjust the recent results of clinical and basic studies of neurological diseases associated with human T-lymphotropic virus type I (HTLV-I) and type 11. HTLV-I and II are type C retroviruses, members of the subfamily Oncoviridae. HTLV-I has been implicated as the causative agent of adult T-cell leukemia/lymphoma (ATL), first proposed as a clinical entity by Takatsuki and colleagues in Japan. This RNA virus was independently isolated from a patient with cutaneous T-cell lymphoma in the United States by Poiesz et al. in 1980 and from a patient with ATL in Japan by Hinuma et al. in 1981. The common causes of neurological complications of ATL were direct tumor cell invasion and hypercalcemia and the manifestations of ATL, including neurological signs and symptoms were variable. Another neurological disease associated with the same HTLV-I has been independently demonstrated in Martinique and Japan. The disease is now known under the combined acronym HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). A nationwide survey in Japan found about 700 cases of HAM/TSP. Approximately 450 persons with HAM/TSP have been reported from other countries, including those in the Caribbean basin, South America and Africa. In the Japanese nationwide survey, the mean age at onset of symptoms was 43 years and the male-to-female ratio of occurrence was 1:2.9. The main neurologic features of HAM/TSP are spasticity and/or hyper-reflexia of lower extremities, urinary bladder disturbance, lower extremity muscle weakness and sensory disturbances (mostly with poorly defined thoracic sensory levels). Histopathologic features consisted of chronic inflammatory changes which were most conspicuous in the lower thoracic cord. There is no convincing proof of virus infection in neural cells and immune pathogenesis for HAM/TSP may play a part. Currently, however, it would be too hasty to draw the conclusion that HTLV-1 infection in neural cells is not related to pathogenic mechanisms for the disease. Oral prednisone may have a beneficial effect in some cases, but effects may be transient. In contrast to HTLV-I, HTLV-II has not been associated conclusively with any specific disease.