The helicase-like transcription factor redirects the autophagic flux and restricts human T cell leukemia virus type 1 infection

Retroviruses and their host have coevolved in a delicate balance between viral replication and survival of the infected cell. In this equilibrium, restriction factors expressed by infected cells control different steps of retroviral replication such as entry, uncoating, nuclear import, expression, or budding. Here, we describe a mechanism of restriction against human T cell leukemia virus type 1 (HTLV-1) by the helicase-like transcription factor (HLTF). We show that RNA and protein levels of HLTF are reduced in primary T cells of HTLV-1-infected subjects, suggesting a clinical relevance. We further demonstrate that the viral oncogene Tax represses HLTF transcription via the Enhancer of zeste homolog 2 methyltransferase of the Polycomb repressive complex 2. The Tax protein also directly interacts with HLTF and induces its proteasomal degradation. RNA interference and gene transduction in HTLV-1-infected T cells derived from patients indicate that HLTF is a restriction factor. Restoring the normal levels of HLTF expression induces the dispersal of the Golgi apparatus and overproduction of secretory granules. By synergizing with Tax-mediated NF-κB activation, physiologically relevant levels of HLTF intensify the autophagic flux. Increased vesicular trafficking leads to an enlargement of the lysosomes and the production of large vacuoles containing viral particles. HLTF induction in HTLV-1-infected cells significantly increases the percentage of defective virions. In conclusion, HLTF-mediated activation of the autophagic flux blunts the infectious replication cycle of HTLV-1, revealing an original mode of viral restriction.

A safe and effective vaccine against bovine leukemia virus

Previous attempts to develop a vaccine against bovine leukemia virus (BLV) have not been successful because of inadequate or short-lived stimulation of all immunity components. In this study, we designed an approach based on an attenuated BLV provirus by deleting genes dispensable for infectivity but required for efficient replication. The ability of the vaccine to protect from natural BLV infection was investigated in the context of dairy productive conditions in an endemic region. The attenuated vaccine was tested in a farm in which the prevalence rose from 16.7% in young cattle at the beginning of the study to more than 90% in adult individuals. Sterilizing immunity was obtained in 28 out of 29 vaccinated heifers over a period of 48 months, demonstrating the effectiveness of the vaccine. As indicated by the antiviral antibody titers, the humoral response was slightly reduced compared to wild-type infection. After initial post-vaccination bursts, the proviral loads of the attenuated vaccine remained most frequently undetectable. During the first dairy cycle, proviral DNA was not detected by nested-PCR in milk samples from vaccinated cows. During the second dairy cycle, provirus was sporadically detected in milk of two vaccinated cows. Forty-two calves born from vaccinated cows were negative for proviral DNA but had antiviral antibodies in their peripheral blood. The attenuated strain was not transmitted to sentinels, further supporting the safety of the vaccine. Altogether, these data thus demonstrate that the vaccine against BLV is safe and effective in herd conditions characterized by a very high incidence. This cost-effective approach will thus decrease the prevalence of BLV without modification of production practices. After facing a series of challenges pertaining to effectiveness and biosafety, the vaccine is now available for further large-scale delivery. The different challenges and hurdles that were bypassed may be informative for the development of a vaccine against HTLV-1.

BLV: lessons on vaccine development

Vaccination against retroviruses is a challenge because of their ability to stably integrate into the host genome, undergo long-term latency in a proportion of infected cells and thereby escape immune response. Since clearance of the virus is almost impossible once infection is established, the primary goal is to achieve sterilizing immunity. Besides efficacy, safety is the major issue since vaccination has been associated with increased infection or reversion to pathogenicity. In this review, we discuss the different issues that we faced during the development of an efficient vaccine against bovine leukemia virus (BLV). We summarize the historical failures of inactivated vaccines, the efficacy and safety of a live-attenuated vaccine and the economical constraints of further industrial development.

[Bioecology in Haiti of Anopheles albimanus Wiedemann, 1820 (Diptera:Culicidae)]

Hispaniola has the highest malaria rate in the West Indies. A study of the bio-ecology of the major vector Anopheles albimanus was carried out in Haïti. Our observations concerned the length of pre-imaginal stages, biting rates and the gonotrophic cycle. A table of its complete life cycle, stage by stage, was produced as well as a graph illustrating its whole larval development in its natural habitat. Results in the field and insectarium were compared. In the laboratory, the development was shorter, except for pupae. The temperature was the main factor governing the length of pre-imaginal development. Preimaginal development decreased from 15 days in the field to 9 days in the insectarium whereas the temperature was a high of 4 degrees C. The nycthemeral activity and seasonal variations of An. albimanus were studied, by monthly all-night captures on human volunteers, during a full year in exo- and endophilic situations. Two sampling sites were chosen for comparison, An. albimanus were caught at every hour of the nycthemeral cycle, with a peak around midnight. Monthly variations were affected by the rains. The vector was more exophagous, when its density was high. The parity rate of the biting population varied between 85.8% and 20.0%; it was low at the beginning of the rains and increased when the rains stopped and breeding places dried out. To study the gonotrophic cycle of wild An. albimanus, several techniques were used jointly; follicles dissection; follicular relics; length of maturation of follicles. The length of the full cycle and of each of its components was estimated (quest of host for blood meal; maturation phase; breeding site seeking). In Haïti 41 h (nulliparous), or 21 h (parous) were necessary for females to have a complete maturation of the follicles. The lengthening of the gonotrophic cycle of parous An. albimanus, in the natural field site, was estimated to last about 4 days. For nulliparous it was 5 days, and 7 days if a pregravid stage was necessary. Considering the sporogonic cycle of Plasmodium falciparum (12 days), the wild population of An. albimanus females could become infective at the third blood feeding in Haïti.

Working with spiritual and religious themes in group therapy

This article explores the analytic therapy group as a spiritual community that can deepen the implications of group transference. From this perspective, group-as-a-whole dynamics include a spiritual dimension in addition to the recapitulation of the family of origin. Clinical vignettes are introduced from a midphase group to illustrate a means of working with spiritual and religious themes psychodynamically through managing them like dreams. Amplification and interpretation of the symbolic themes guide members through the transference to the family of origin. There, members gain access to childhood memories and to the childhood transitional space of religious experience where they created their God representations as a means of solving their self and object dilemmas. The working-through process facilitates the integration or transformation of new self and God images.

Is fragile X syndrome a pervasive developmental disability? Cognitive ability and adaptive behavior in males with the full mutation

In addition to mental retardation (MR), fragile X [fra(X)] syndrome has been associated with various psychopathologies, although it appears that the link is secondary to MR. It has been proposed that individuals with the full mutation be classified as a subcategory of pervasive developmental disorders (PDD). If fra(X) males are to be categorized as PDD, how do they compare with other types of developmental disabilities? We examined 27 fra(X) males aged 3-14 years, from 4 sites in North America. Measures of cognitive abilities were obtained from the Stanford-Binet Fourth Edition (SBFE), while levels of adaptive behavior were evaluated using the Vineland Adaptive Behavior Scales (VABS). Control subjects were sex-, age-, and IQ matched children and adolescents ascertained from the Developmental Evaluation Clinic (DEC) at Kings County Hospital. At the DEC, control subjects were diagnosed as either MR (n = 43) or autistic disorder (AD; n = 22). To compare subjects' adaptive behavior (SQ) with their cognitive abilities (IQ), a ratio of [(SQ/IQ) x 100] was computed. Results graphed as cumulative distribution functions (cdf) revealed that the cdf for AD males, who by definition are socially impaired, was positioned to the left of the cdf for MR controls, as expected. Mean ratio for AD males (70) was lower than for MR males (84). On the other hand, the cdf for fra(X) males was positioned far to the right of either AD or MR controls (mean ratio = 125). Statistical tests showed that SQ of fra(X) males was significantly higher than controls.(ABSTRACT TRUNCATED AT 250 WORDS)