BACKGROUND: Human T-cell lymphotropic virus type I (HTLV-I) is a retrovirus that has been identified as a cause of adult T-cell leukemia/lymphoma and tropical spastic paraparesis. HTLV-I infection is highly endemic in the southwestern islands of Japan, Caribbean basin, South America, and Africa. In 1993, we showed that the seroprevalence of antibodies to HTLV-I was 0.13% among blood donors in Korea, but surprisingly, 0.80% in Cheju-Do adjacent to endemic areas of Japan. So this study was designed to reevaluate the seroprevalence of antibodies to HTLV-I among residents in Cheju-Do. METHODS: Total 2,372 residents in Cheju-Do were tested from December 1995 to March 1996. Anti-HTLV-I antibodies were detected by the microtiter particle agglutination test. RESULTS: Among total 2,372 residents, 19 were anti-HTLV-I positive. So the overall positive rate of anti-HTLV-I antibodies was 0.80%. The positive rate in females was higher than in males (0.82% vs 0.78%). The positive rate was 1.45% in the age group of 20-29 years, 1.41% in 40-49 years, 0.91% in 0-9 years, 0.70% in 30-39 years, and 0.54% in 50-59 years. The mean age of seropositive cases is 35.2 in males and 35.4 in females, with a mean of 35.3. Geographically, high positive rate was observed in Sogwipo-City (1.37%) and Namcheju-Gun (0.83%) compared to those of Pukcheju-Gun (0.64%) and Cheju-City (0.61%), which showed high seroprevalence in districts adjacent to endemic areas of Japan. Any specific risk factors or associated disorders of HTLV-I infection could not be found among the seropositive cases. CONCLUSION: The seroprevalence of antibodies to HTLV-I in Cheju-Do was noted to be very high by the microtiter particle agglutination test. So henceforth serosurvey by confirmative laboratory tests is needed, and if high seroprevalence is showed from it, screening of blood donors for HTLV-I in Cheju-Do should be considered to prevent transfusion-associated HTLV-I infection.
Adult ; Africa ; Agglutination Tests ; Antibodies ; Blood Donors ; Caribbean Region ; Epidemiology ; Female ; HTLV-I Infections ; Human T-lymphotropic virus 1 ; Humans* ; Islands ; Japan ; Jeju-do* ; Korea ; Male ; Mass Screening ; Paraparesis, Tropical Spastic ; Retroviridae ; Risk Factors ; Seroepidemiologic Studies* ; South America ; T-Lymphocytes*

OBJECTIVETo study the seroprevalence of human T-cell leukaemia virus type I/II (HTLV-I/II) infection in adult population in the east coastal areas of Fujian and to explore the possible risk factors of HTLV-I/II.

METHODSA total number of 3259 blood samples from drug users, sexually transmitted disease (STD) patients, prostitutes and blood donors for serologic assays during 1999 to 2002, were collected. All samples were screened for HTLV-I/II antibody, using enzyme linked immunosorbent assay (ELISA) kits. All of the positive samples were confirmed by western blot (WB) kits. Statistical analysis was done by Epi software, and chi(2) test by Fisher's exact test. P value < 0.05 was considered statistically significant.

RESULTSThe overall seroprevalence rate of HTLV-I/II in healthy populations was 0.06% including, 0.32% in drug users, 0.58% in STD patients and prostitutes respectively. HTLV-II had not been found. The seropositive rates for HTLV-I in STD patients and prostitutes were significantly higher than the findings among healthy populations (P < 0.05). There were no different seroprevalence rates between drug users and healthy populations (P > 0.05). No significant changes in HTLV-I prevalence rates were found in the different age groups as well as in Fuzhou and Linde cities (P > 0.05).

CONCLUSIONThe result suggested that in the east coastal areas of Fujian province, HTLV-I was the main prevalent virus. The seroprevalence of HTLV-I was very low, with no HTLV-II. Neither age nor gender seemed to be HTLV-I risk factor in the east coastal areas of Fujian province, but the increase of exposure to sex might be one.

China ; epidemiology ; DNA, Viral ; isolation & purification ; Female ; HTLV-I Antibodies ; blood ; HTLV-I Antigens ; immunology ; HTLV-I Infections ; diagnosis ; epidemiology ; HTLV-II Antibodies ; blood ; HTLV-II Antigens ; immunology ; HTLV-II Infections ; diagnosis ; epidemiology ; Human T-lymphotropic virus 1 ; genetics ; immunology ; isolation & purification ; Human T-lymphotropic virus 2 ; genetics ; immunology ; isolation & purification ; Humans ; Male ; Prevalence ; Seroepidemiologic Studies ; Sexually Transmitted Diseases, Viral ; epidemiology

Human T-cell leukemia virus type 1 (HTLV-1) is a retrovirus demonstrated to be associated with human disease. Infection by the HTLV-1 can cause T-cell leukemia (ATL) in adults. HTLV-1 bZIP factor (HBZ) is a viral protein encoded by the minus strand of the HTLV-1 provirus. Among the regulatory and accessory genes of HTLV-1, HBZ is the only gene that remains intact and which is expressed consistently in all patients with ATL. Moreover, HBZ has a critical role in the leukemogenesis of ATL. Here, we review the function of HBZ in the oncogenesis of HTLV-1 and its molecular mechanism of action.
Animals ; Basic-Leucine Zipper Transcription Factors ; genetics ; metabolism ; Carcinogenesis ; HTLV-I Infections ; pathology ; virology ; Human T-lymphotropic virus 1 ; genetics ; metabolism ; Humans ; Leukemia, T-Cell ; pathology ; virology ; Retroviridae Proteins ; genetics ; metabolism

BACKGROUND: We reported that human T cell leukemia virus 1 (HTLV-1) infection is positively associated with atherosclerosis. Recent evidence has revealed a close association of periodontitis with atherosclerosis, endothelial dysfunction, and disruption of the microcirculation. However, the association between HTLV-1 and advanced periodontitis has not been investigated to date. Since hematopoietic activity is closely linked to endothelial maintenance activity and is known to decline with age, we hypothesized that the state of hematopoietic activity influenced the association between HTLV-1 and advanced periodontitis in elderly participants. METHODS: A cross-sectional study was performed including 822 elderly participants aged 60-99 years who participated in a dental health check-up. Advanced periodontitis was defined as a periodontal pocket ≥ 6.0 mm. Participants were classified as having low or high hematopoietic activity according to the median values of reticulocytes. RESULTS: HTLV-1 infection was positively related to advanced periodontitis among participants with lower hematopoietic activity (lower reticulocyte count), but not among participants with higher hematopoietic activity (higher reticulocyte count). The adjusted odds ratio (95% confidence interval) considering potential confounding factors was 1.92 (1.05-3.49) for participants with a lower reticulocyte count and 0.69 (0.35-1.36) for participants with a higher reticulocyte count. CONCLUSIONS Among elderly participants, the association between HTLV-1 infection and advanced periodontitis is influenced by hematopoietic activity. Since hematopoietic activity is associated with endothelial maintenance, these findings provide an efficient tool for clarifying the underlying mechanism of the progression of periodontitis among elderly participants.
Aged ; Aged, 80 and over ; Cross-Sectional Studies ; Female ; HTLV-I Infections ; physiopathology ; Hematopoiesis ; physiology ; Human T-lymphotropic virus 1 ; physiology ; Humans ; Japan ; epidemiology ; Male ; Middle Aged ; Odds Ratio ; Periodontitis ; epidemiology ; virology ; Prevalence ; Risk Factors

BACKGROUND: Human T-cell leukemia virus type 1 (HTLV-1) activates inflammatory cascades by activating the NF-κB pathway. The minor allele of single nucleotide polymorphism (SNP) in breast cancer suppressor BRCA1-associated protein (BRAP), which has a common etiology with HTLV-1 infection, has been reported to be positively associated with carotid atherosclerosis, but inversely associated with hypertension. Therefore, HTLV-1 infection may be inversely associated with hypertension by activating endothelial maintenance, including atherosclerosis. To clarify these associations, a cross-sectional study was conducted using 2989 Japanese individuals aged 60-99 years participating in a general health check-up. METHODS: Logistic regression models were used to clarify the association between HTLV-1 and hypertension. Platelet levels stratified analyses were also performed since platelet production, which plays a crucial role in endothelium maintenance, can be stimulated by activating the NF-κB pathway. RESULTS: HTLV-1 infection was found to be significantly inversely associated with hypertension, particularly in subjects with high platelet levels (≥ second tertiles of platelet levels); the fully adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were 0.75 (0.62, 0.92) for total and 0.64 (0.50, 0.82) for high platelet levels, respectively. Further analysis of the non-hypertensive subjects demonstrated that HTLV-1 infection was significantly positively associated with atherosclerosis in subjects with the highest tertile of platelet levels (2.11 [1.15, 3.86]) but not in subjects with low platelet levels (first and second tertiles of platelet level) (0.89 [0.57, 1.39]). CONCLUSION Asymptomatic HTLV-1 infection is inversely associated with hypertension, possibly by activating endothelial maintenance, including atherosclerosis progression.
Aged ; Aged, 80 and over ; Carotid Artery Diseases/virology* ; Cross-Sectional Studies ; Female ; HTLV-I Infections/complications* ; Human T-lymphotropic virus 1/physiology* ; Humans ; Hypertension/virology* ; Japan/epidemiology* ; Male ; Middle Aged

We experienced a case of adult T cell leukemia/lymphoma (ATLL) in a 48-year-old Korean female, who has never been abroad since birth and no history of blood transfusion. The patient had hypercalcemia and multiple lymphadenopathy. Histopathologic study of left cervical lymph node (LN) and bone marrow (BM) revealed that infiltrates of malignant lymphoid cells were composed of small, medium and large cells with pleomorphic nuclei. Smears of peripheral blood (PB) showed lymphopenia (16%) with the appearance of a few atypical lymphoid cells (less than 2%), but not the typical clover leaf cells seen in ATLL. Immunophenotypic study of LN and BM revealed T cell phenotype. PB showed increased CD4+ T cell (T(H), CD3/CD4+, 57%) and decreased CD8+ T cell counts (T(S), CD3/CD8+, 6.7%). The sera of the patient and her family were reactive for HTLV-I antibody. The specific sequences of pol, env, and tax of HTLV-I DNA were detected in the lymphoma cells and peripheral blood mononuclear cells (PBMC) using polymerase chain reaction. Ultrastructural examination of PBMC confirmed numerous type c virus particles in extracellular space. This case was an acute type of ATLL without overt leukemic features in PB. Despite chemotherapy and intensive conservative treatment, she died 3 months after admission.
Biopsy ; Bone Marrow/pathology ; Case Report ; DNA, Viral/analysis ; Fatal Outcome ; Female ; Flow Cytometry ; Gene Products, env/genetics ; Gene Products, pol/genetics ; Gene Products, tax/genetics ; HTLV-BLV Infections/pathology ; HTLV-I ; Human ; Hypercalcemia/virology ; Hypercalcemia/pathology ; Immunophenotyping ; Korea ; Leukemia, T-Cell/virology ; Leukemia, T-Cell/pathology* ; Leukemia, T-Cell/immunology ; Lymph Nodes/pathology ; Lymphopenia/virology ; Lymphopenia/pathology* ; Lymphopenia/immunology ; Microscopy, Electron ; Middle Age ; Support, Non-U.S. Gov't ; T-Lymphocytes/virology ; T-Lymphocytes/ultrastructure ; T-Lymphocytes/pathology

We report the first Korean case of HTLV-I associated myelopathy (HAM), which was confirmed by Western blot assay of serum and cerebrospinal fluid. Interestingly, the proband's wife was a Japanese Korean who had lived in the endemic area of HAM, Kyushu. Japan, Investigations revealed significantly elevated anti HTLV-I antibody titers in the serum, but not in the CSF, suggesting that she was a carrier of HTLV-I. Considering that the patient had not had a previous blood transfusion, the most common route of HTLV-I, it is likely that the patient was infected by his wife through sexual intercourse. Although previous reports suggest that the transmission of HTLV-I is essentially from man to man or man to woman, our case suggests that woman to man transmission also occurs.
Adult ; Blotting, Western ; HTLV-I Antibodies/analysis ; Human ; Korea/epidemiology ; Male ; Paraparesis, Tropical Spastic/*epidemiology/immunology

Limited nucleotide sequences of human T-cell lymphotropic virus type I (HTLV-1) provirus isolated from the first case of a Korean patient with HTLV-I associated myelopathy and tropical spastic paraparesis (HAM/TSP) were analysed and compared with other isolates from different regions of the world. The sequences of the env, LTR regions (536bp, 690bp respectively) showed 98.7%, 99.3% homologies with the prototype HTLV-I, ATK-1, isolated from a Japanese Adult T-cell leukemia (ATL) patient. A comparison between other isolates from different geographical origins revealed that the Korean HTLV-I isolate is more closely related to Japanese isolates than to those from other geographical origins
Adult ; Base Sequence ; Case Report ; DNA, Viral/genetics ; Human ; Human T-lymphotropic virus 1/*genetics/isolation & purification ; Korea/ethnology ; Male ; Molecular Probes/genetics ; Molecular Sequence Data ; Paraparesis, Tropical ; Spastic/epidemiology/ethnology/*genetics/*microbiology