Highlights from the HTLV-1 symposium at the 2017 Australasian HIV and AIDS Conference held jointly with the 2017 Australasian Sexual Health Conference, November 2017, Canberra, Australia

Treatment with Antiviral Drugs Will Significantly Inhibit the HIV-1 RNA POL Gene Expression and Viral Load in AIDS Patients

Objective

This study is to investigate the difference in HIV-1 RNA pol gene expression in AIDS patients before and after antiviral treatment and its effect on the expression level of CD4+/CD8+ T cells in peripheral blood.

Methods

The participants included 200 AIDS patients who had undergone antiviral medication, and the quantity of HIV-1 RNA pol gene was determined using nested polymerase chain reaction (nPCR). The levels of CD3+, CD4+, and CD8+ T lymphocytes in peripheral blood were measured by flow cytometry before and after therapy. The receiver operating characteristics (ROC) curve was used to assess the impact of HIV-1 RNA pol gene expression and the CD4+/CD8+ ratio on the prognosis of AIDS patients.

Results

After three months of therapy, the levels of HIV-1 RNA and viral load in the patients showed a drastic decline, while the levels of CD4+/CD8+ were markedly elevated (P < 0.05). Logistic analysis revealed that patients' viral loads were positively correlated with HIV-1 RNA and negatively correlated with CD4+/CD8+ (P < 0.05). The alanine aminotransferase (ALT), white blood cell (WBC) count, Serum creatinine (Cr), total cholesterol (TC), triglyceride (TG), and platelet (PLT) levels significantly increased following a 24-month therapy, while no significant changes were observed in the level of aspartate aminotransferase (AST), red blood cell (RBC), and neutrophil (NEU) (%). (P > 0.05).

Conclusion

Antiviral drugs significantly inhibit the HIV-1 RNA POL gene expression and viral load in AIDS patients but upregulate the expression level of CD4+/CD8+ T cells in peripheral blood.

A Qualitative Study Exploring Perceptions to the Human T Cell Leukaemia Virus Type 1 in Central Australia: Barriers to Preventing Transmission in a Remote Aboriginal Population

Background

Central Australia has the highest recorded prevalence of infection with the human T cell leukaemia virus type 1 (HTLV-1) worldwide. Each of the clinical diseases associated with HTLV-1 have been reported in this region, including deaths due to adult T cell leukaemia, which is causally linked to HTLV-1. Nevertheless, no public health response has been implemented to reduce HTLV-1 transmission among the affected Aboriginal population. In the first study to explore the perceptions of healthcare professionals along with those of Aboriginal people whose communities are actually impacted by HTLV-1, we sought to understand the barriers to preventing HTLV-1 transmission in this remote area.

Methodology/Principal Findings

Semi and un-structured interviews were conducted with 30 Australian Aboriginal people, 26 non-Aboriginal healthcare professionals and 3 non-Aboriginal community workers. The purpose of the interviews was to explore perceptions towards HTLV-1 in a health context with a focus on sexual and reproductive rights. Deductive and inductive analyses were applied to the data and a decolonizing lens brought peripheral stories to the fore. A major finding was the contrast between views expressed by Aboriginal participants and healthcare professionals regarding the provision of knowledge to those affected. Aboriginal participants consistently articulated that they and their communities should be informed of, and can hold, knowledges pertaining to HTLV-1. This finding controverted the perceptions of healthcare professionals that the complexities of the virus would not be well-understood by their Aboriginal patients and that sharing HTLV-1 knowledges might overwhelm Aboriginal people. Further analyses revealed a spectrum of understanding and clinical practice, while also delineating signs of an imagined public health response.

Conclusions/Significance

HTLV-1 remains a neglected infection in Australia. Knowledge of HTLV-1 is held by a privileged medical elite and does not flow to marginalised Aboriginal people living in affected communities. We demonstrate that differences in the perspectives of stakeholders presents a significant barrier to the development of cohesive, culturally safe prevention programs that foster a shared knowledge of HTLV-1. The interview data suggests that a successful public health program is likely to require a dual approach that includes clinical care and community-driven health promotion. Aspects of this approach, which would raise awareness and potentially reduce transmission and lower HTLV-1 prevalence in Central Australia, may be applicable to other endemic settings with similar conditions of social disadvantage, geographic remoteness, resource limitations and cross-cultural challenges.

Perceived benefits, challenges, and recommendations for HIV research dissemination and implementation science efforts in Tanzania: Findings from the HIV/AIDS Research Forum brainstorming session

Although several international and national HIV/AIDS conferences exist, there was not a national conference in Tanzania focusing on HIV/AIDS disseminating and implementation research conducted in the country and abroad. This created a missed opportunity for researchers to share their research findings with local policymakers and HIV program implementers who can influence the adoption and implementation of promising research in public health and clinical practice settings. In response, the first HIV/AIDS D&I Research Forum designed to enhance local D&I efforts for HIV research, was organized in Tanzania in 2018. This paper explores the perceived benefits of the HIV/AIDS D&I Research Forum and potential challenges of developing similar forums and recommendation for future HIV research D&I conference in Tanzania. During the second day of the Forum, which was held in September 2018 in Morogoro, Tanzania, a 1-hour structured brainstorming session was conducted with the Forum attendees (n = 50), including researchers, medical professionals, policymakers, representatives from different ministries. Transcription of the brainstorming session was analyzed to identify benefits of the Forum, perceived challenges for organizing similar HIV/AIDS research dissemination events, and recommendations for addressing the challenges. Overall, participants perceived the forum to be beneficial because it provided opportunities for strategic collaborations between researchers, policymakers, and other stakeholders and for them to discuss challenges for D&I efforts. Forum attendees also identified several potential challenges for future D&I research forums such as the abstract requirement which may deter non-researchers, costs, meeting frequencies, and lack of funding and coordination between organizations involved in D&I research efforts. To address these concerns, a recommendation was made to host a biennial national conference in order to allow more time for ethical review and feedback that can enhance contribution of the project to D&I efforts and to raise funds. The benefits identified for the Forum highlight the importance of organizing similar D&I meetings for HIV-related research at the national level in Tanzania. However, the potential challenges discussed need to be addressed in order to develop a sustainable national D&I research conference by incorporating recommendations that forum attendees proposed.

Molecular epidemiology, genetic variability and evolution of HTLV-1 with special emphasis on African genotypes

Human T cell leukemia virus (HTLV-1) is an oncoretrovirus that infects at least 10 million people worldwide. HTLV-1 exhibits a remarkable genetic stability, however, viral strains have been classified in several genotypes and subgroups, which often mirror the geographic origin of the viral strain. The Cosmopolitan genotype HTLV-1a, can be subdivided into geographically related subgroups, e.g. Transcontinental (a-TC), Japanese (a-Jpn), West-African (a-WA), North-African (a-NA), and Senegalese (a-Sen). Within each subgroup, the genetic diversity is low. Genotype HTLV-1b is found in Central Africa; it is the major genotype in Gabon, Cameroon and Democratic Republic of Congo. While strains from the HTLV-1d genotype represent only a few percent of the strains present in Central African countries, genotypes -e, -f, and -g have been only reported sporadically in particular in Cameroon Gabon, and Central African Republic. HTLV-1c genotype, which is found exclusively in Australo-Melanesia, is the most divergent genotype. This reflects an ancient speciation, with a long period of isolation of the infected populations in the different islands of this region (Australia, Papua New Guinea, Solomon Islands and Vanuatu archipelago). Until now, no viral genotype or subgroup is associated with a specific HTLV-1-associated disease. HTLV-1 originates from a simian reservoir (STLV-1); it derives from interspecies zoonotic transmission from non-human primates to humans (ancient or recent). In this review, we describe the genetic diversity of HTLV-1, and analyze the molecular mechanisms that are at play in HTLV-1 evolution. Similar to other retroviruses, HTLV-1 evolves either through accumulation of point mutations or recombination. Molecular studies point to a fairly low evolution rate of HTLV-1 (between 5.6E−7 and 1.5E−6 substitutions/site/year), supposedly because the virus persists within the host via clonal expansion (instead of new infectious cycles that use reverse transcriptase).

Absence of accessory genes in a divergent simian T-lymphotropic virus type 1 isolated from a bonnet macaque (Macaca radiata)

Background

Primate T-lymphotropic viruses type 1 (PTLV-1) are complex retroviruses infecting both human (HTLV-1) and simian (STLV-1) hosts. They share common epidemiological, clinical and molecular features. In addition to the canonical gag, pol, env retroviral genes, PTLV-1 purportedly encodes regulatory (i.e. Tax, Rex, and HBZ) and accessory proteins (i.e. P12/8, P13, P30). The latter have been found essential for viral persistence in vivo.

Methodology/Principal findings

We have isolated a STLV-1 virus from a bonnet macaque (Macaca radiata–Mra18C9), a monkey from India. The complete sequence was obtained and phylogenetic analyses were performed. The Mra18C9 strain is highly divergent from the known PTLV-1 strains. Intriguingly, the Mra18C9 lacks the 3 accessory open reading frames. In order to determine if the absence of accessory proteins is specific to this particular strain, a comprehensive analysis of the complete PTLV-1 genomes available in Genbank was performed and found that the lack of one or many accessory ORF is common among PTLV-1.

Conclusion

This study raises many questions regarding the actual nature, role and importance of accessory proteins in the PTLV-1 biology.

Primate T-lymphotropic viruses type 1 (PTLV-1) are complex retroviruses infecting both human (HTLV-1) and simian (STLV-1) hosts. It has been shown that the persistence and pathogenesis of these viruses depend on the expression of small, accessory proteins.

A bonnet macaque (a monkey present in India) was found infected with STLV-1. The genome was sequenced and found quite divergent from the other STLV-1 genomes previously described. Intriguingly, this virus does not encode accessory proteins. Analysis of other available sequences found that most strains lack at least one accessory gene. Thus the importance and the role of these proteins in the PTLV-1 biology should be revisited.

HTLV-1 is rare in Far North Queensland despite a significant burden of classically associated diseases

Human T-lymphotropic virus type 1 (HTLV-1) is hyperendemic amongst Indigenous Australians living in Central Australia. The epidemiology of the disease is poorly defined in other parts of Australia, despite a high prevalence of classically associated conditions. All HTLV-1 serology tests requested through public health facilities in Far North Queensland (FNQ) from January 1999 to December 2016 were reviewed. The person's age, sex, ethnicity, location, rationale for testing and result were recorded. There were 444 tests performed in 409 people; 217 (53%) were male; 171 (42%) identified as Indigenous Australians. Testing increased over time and was performed throughout the region, suggesting increasing awareness of the disease. Testing occurred in patients with haematological, neurological, dermatological and respiratory complaints, but only four (1%) had proven infection. Three of these individuals were in the same family and two were asymptomatic. One of the two symptomatic seropostive individuals had recurrent scabies infection, the other T-cell lymphoma. HTLV-1 infection is extremely uncommon in FNQ. The high rates of bronchiectasis and other associated conditions that are seen in the region are more likely to be addressed by public health policies focusing on the socioeconomic determinants of health.

Performance of Commercially Available Serological Screening Tests for Human T-Cell Lymphotropic Virus Infection in Brazil

Serological screening for human T-cell lymphotropic virus type 1 (HTLV-1) is usually performed using enzyme-linked immunosorbent assay (ELISA), particle agglutination, or chemiluminescence assay kits. Due to an antigen matrix improvement entailing the use of new HTLV antigens and changes in the format of HTLV screening tests, as well as newly introduced chemiluminescence assays (CLIAs), a systematic evaluation of the accuracy of currently available commercial tests is warranted. We aimed to assess the performance of commercially available screening tests for HTLV infection diagnosis. A diagnostic accuracy study was conducted on a panel of 397 plasma samples: 200 HTLV-negative plasma samples, 170 HTLV-positive plasma samples, and 27 plasma samples indeterminate by Western blotting (WB). WB-indeterminate samples (i.e., those yielding no specific bands for HTLV-1 and/or HTLV-2) were assessed by PCR, and the results were used to compare agreement among the commercially available ELISA screening tests. For performance analysis, WB-indeterminate samples were excluded, resulting in a final study panel of 370 samples. Three ELISA kits (Murex HTLV-1/2 [Murex], anti-HTLV-1/2 SYM Solution [SYM Solution], and Gold ELISA HTLV-1/2 [Gold ELISA]) and one CLIA kit (Architect rHTLV-1/2) were evaluated. All screening tests demonstrated 100% sensitivity. Concerning the HTLV-negative samples, the SYM Solution and Gold ELISA kits had specificity values of >99.5%, while the Architect rHTLV-1/2 test presented 98.1% specificity, followed by Murex, which had a specificity of 92.0%. Regarding the 27 samples with WB-indeterminate results, after PCR confirmation, all ELISA kits showed 100% sensitivity but low specificity. Accuracy findings were corroborated by the use of Cohen's kappa value, which evidenced slight and fair agreement between PCR analysis and ELISAs for HTLV infection diagnosis. Based on the data, we believe that all evaluated tests can be safely used for HTLV infection screening.

2017 international meeting of the Global Virus Network

The Global Virus Network (GVN) was established in 2011 to strengthen research and responses to emerging viral causes of human disease and to prepare against new viral pandemics. There are now 40 GVN Centers of Excellence and 6 Affiliate laboratories in 24 countries. The 2017 meeting was held from September 25–27 in Melbourne, Australia, and was hosted by the Peter Doherty Institute for Infection and Immunity and the Institut Pasteur. This report highlights the recent accomplishments of GVN researchers in several important areas of medical virology, including the recent Zika epidemic, infections by human papillomavirus, influenza, HIV, hepatitis C, HTLV-1, and chikungunya viruses, and new and emerging viruses in the Australasia region. Plans for the 2018 meeting also are noted.

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The GVN is an international research network comprised of 40 Centers of Excellence and 6 Affiliates in 24 countries.

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The 2017 Global Virus Network (GVN) Meeting was held in Melbourne, Australia from September 25–27.

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New data were presented on various aspects of medical virology, therapies, and emerging viruses in the Australasia region.

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International collaboration is critical to developing new and effective viral vaccines and therapeutics.

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The 2018 international GVN meeting will be held on November 28–30 in Annecy, France.