TLV-1-associated myelopathy in China

This case report documents the first patient from main land China with an HTLV-1-associated myelopathy. The available epidemiological data suggest a low rate of HTLV 1 infection in China, although the surveys are comparatively small. Possible transmission routes and the risk of encountering the disease outside endemic areas are discussed.     

Prevalence of human T-Cell lymphotropie virus infections in Germany

The extent of human T-cell lymphotropic retorvirus HTLV-I and HTLV-II infections in the general population in central Europe has not been investigated fully. Two hundred forty-eight thousand blood donors from southern Germany were examined serologically for antibodies to the human lymphotropic retroviruses HTLV-I and HTLV-II: 0.021% were confirmed postive and 0.056% were “indeterminate”. A limited number of seropositives and “indeterminate” samples were analyzed by polymerase chain reaction (PCR): the seropositives were confirmed as positive and 43% of the “indeterminate” samples were PCR-positive. The range of 0.021% HTLV-positives in 248,000 donors, i.e. about two in 10,000 individuals, mirrors closely the published data for the United States. © 1994 Wiley-Liss, Inc.     

Sendai virus particles carrying target virus glycoproteins for antibody induction

Induction of antibodies targeting viral glycoproteins is a key for the development of a vaccine against enveloped virus infection. Glycoproteins on the virion exhibiting native multimer structure may be a good immunogen to present antibody epitopes, but it is often difficult to prepare immunogenic inactivated virions. Preparation of soluble glycoprotein multimers has been attempted, while virus-like particles carrying target glycoproteins can be a more immunogenic antigen. In the present study, a target glycoprotein-embedded Sendai virus (SeV) particle was developed for induction of anti-virus antibodies. We constructed a chimeric antigen, HIV-1 EnvF, consisting of HIV-1 Env ectodomain and SeV F transmembrane-cytoplasmic domain, which was shown to be efficiently incorporated into the SeV virion. EnvF was recognized by anti-HIV-1 broadly-neutralizing monoclonal antibodies (bnAbs) including 35O22 that targets an Env trimer-dependent epitope. Analysis revealed that HIV-1_AD8 EnvF can mediate viral entry into the cells, which is inhibited by anti-HIV-1 bnAbs and HIV-1 entry inhibitors, suggesting that the EnvF exhibits an HIV-1 Env native-like functional structure to present bnAb epitopes. Immunization of mice with replication-defective SeVs expressing HIV EnvF and non-infectious SeV particles (NVP) carrying HIV EnvF efficiently induced anti-HIV Env antibodies. HTLV-1 EnvF also showed the potential to efficiently induce anti-HTLV-1 Env antibodies. These results indicate that SeV particles carrying EnvF can be a promising vaccine platform for induction of antibodies targeting enveloped virus glycoproteins.     

Loss of CD7, independent of galectin-3 expression, implies a worse prognosis in adult T-cell leukaemia/lymphoma

Aims:  Loss of CD7 is characteristic of adult T-cell lymphoma/leukaemia (ATLL). Galectin-3 (Gal-3) is strongly induced in cultured human T lymphotropic virus-1-infected T lymphocytes, and may cause apoptosis through interaction with CD7. The aim was to investigate the clinical relevance of the Gal-3–CD7 pathway in ATLL.
Methods and results:  Immunohistochemistry for Gal-3 and CD7 was performed on 22 cases of ATLL in the leukaemic phase. We found that the lymphoma cells were not necessarily Gal-3+, but Gal-3+ stromal cells could always be found. Independent of the status of Gal-3, there was an association of loss of CD7 with a worse prognosis.
Conclusions:  These data suggest that, by down-regulating CD7, ATLL cells could have escaped Gal-3-induced apoptosis to run a more aggressive clinical course.     

Deleted HTLV provirus in peripheral blood cells of a patient with T-cell prolymphocytic leukaemia

We describe the first case of T-cell prolymphocytic leukaemia (T-PLL) in which the peripheral blood cells contained a human T-lymphotropic virus (HTLV) related tax sequence. Serum screening tests for anti-HTLV-I/II antibodies were negative. Polymerase chain reaction disclosed the presence of an HTLV-I tax sequence in the peripheral blood. Other sets of oligonucleotide primers for HTLV-I gag , pol , env and the long terminal repeat regions and for the HTLV-II pol region were negative in the DNA of the cells. Although patients with T-PLL have been reported to be seronegative for HTLV-I, our findings point to the possibility that HTLV-I infection might be involved in the aetiology of at least some cases of T-PLL and that there may be alternative mechanisms involved in HTLV-associated leukaemogenesis.     

Fine‐scale geographic clustering pattern of human T‐cell leukemia virus type 1 infection among blood donors in Kyushu‐Okinawa,Japan

Human T‐cell leukemia virus type I (HTLV‐1) infection is endemic in Japan, particularly clustered in the southwestern district, Kyushu‐Okinawa, which consists of eight prefectures that further consist of 274 municipalities. However, no information is available about the fine‐scale distribution of HTLV‐1 infection within Kyushu‐Okinawa. To assess the municipal‐level distribution of people with HTLV‐1 infection in Kyushu‐Okinawa, we performed a cross‐sectional study using a fine‐scale geographic information system map based on HTLV‐1 screening test results from the Japanese Red Cross database from September 2012 to February 2014. Of the 881 871 (646 914 male, 234 957 female) screened blood donors, 981 were seropositive for HTLV‐1 by confirmatory test. The seroprevalence was 0.11% (95% confidence interval [CI] 0.10%‐0.12%) for all, 0.094% (95% CI, 0.09%‐0.10%) for male, and 0.16% (95% CI, 0.14%‐0.18%) for female individuals. The sex‐ and age‐specific HTLV‐1 seroprevalence varied significantly across municipalities; particularly, the seroprevalence among women aged 50 years was significantly higher than that of men in both the mainland of Kyushu‐Okinawa and the satellite island, in all of which the seroprevalence of HTLV‐1 was more than 1.2%. These results show that, even in the Kyushu‐Okinawa district, there are endemic clusters of HTLV‐1 in small areas. This suggests that public health education programs are needed to eliminate new HTLV‐1 infection in these areas.