The binding potential of commercial antibody conjugates with sera of various small terrestrial mammals

Infectious diseases of wild animals are of increasing importance, both from an economic viewpoint and because several of these diseases are pathogenic to man. However, serosurveys to determine the circulation of infectious organisms in wildlife are complicated by the fact that antibodies to species-specific immunoglobulins are not available for use in serological assays such as enzyme-linked immunosorbent assays (ELISAs) or immunofluorescence assays. To determine the binding potential of four commercially available antibody conjugates with the sera of wild animals, sera from 27 species of small terrestrial mammals were allowed to react with alkaline phosphatase-labelled protein A, anti-rabbit lgG, anti-mouse lgG and anti-human lgG by by the use of an ELISA. It was found that sera from some species of the order Lagomorpha bound optimally to anti-rabbit lgG, while anti-mouse lgG could be used for most species of Rodentia. For all Carnivora, lnsectivora, Macroscelidea, Hyracoidea and other Rodentia, staphylococcal protein A demonstrated optimal binding. None of the sera that was tested bound to anti-human lgG. These results demonstrate that commercial conjugates can be used in serological assays in which wild animal sera are used, and should be useful for future serosurveys to determine the circulation of infectious agents in small terrestrial mammals.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat X Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format

An exploratory survey measuring stigma and discrimination experienced by people living with HIV/AIDS in South Africa : the People Living with HIV Stigma Index

Background: The continued presence of stigma and its persistence even in areas where HIV prevalence is high makes it an extraordinarily important, yet difficult, issue to eradicate. The study aimed to assess current and emerging HIV/AIDS stigma and discrimination trends in South Africa as experienced by people living with HIV/AIDS (PLHIV). Methods: The PLHIV Stigma Index, a questionnaire that measures and detects changing trends in relation to stigma and discrimination experienced by PLHIV, was used as the survey tool. The study was conducted in 10 clinics in four provinces supported by the Foundation for Professional Development (FPD), with an interview total of 486 PLHIV. A cross-sectional design was implemented in the study, and both descriptive and inferential analysis was conducted on the data. Results: Findings suggest that PLHIV in this population experience significant levels of stigma and discrimination that negatively impact on their health, working and family life, as well as their access to health services. Internalised stigma was prominent, with many participants blaming themselves for their status. Conclusion: The findings can be used to develop and inform programmes and interventions to reduce stigma experienced by PLHIV. The current measures for dealing with stigma should be expanded to incorporate the issues related to health, education and discrimination experienced in the workplace, that were highlighted by the study.Psycholog

Predictors of early death in a cohort of Ethiopian patients treated with HAART

BACKGROUND: HAART has improved the survival of HIV infected patients. However, compared to patients in high-income countries, patients in resource-poor countries have higher mortality rates. Our objective was to identify independent risk factors for death in Ethiopian patients treated with HAART. METHODS: In a district hospital in Ethiopia, we treated adult HIV infected patients with HAART based on clinical and total lymphocyte count (TLC) criteria. We measured body weight and complete blood cell count at baseline, 4 weeks later, then repeated weight every month and complete blood cell count every 12 weeks. Time to death was the main outcome variable. We used the Kaplan Meier and Cox regression survival analyses to identify prognostic markers. Also, we calculated mortality rates for the different phases of the follow-up. RESULTS: Out of 162 recruited, 152 treatment-naïve patients contributed 144.1 person-years of observation (PYO). 86 (57%) of them were men and their median age was 32 years. 24 patients died, making the overall mortality rate 16.7 per 100 PYO. The highest death rate occurred in the first month of treatment. Compared to the first month, mortality declined by 9-fold after the 18(th )week of follow-up. Being in WHO clinical stage IV and having TLC<= 750/mcL were independent predictors of death. Haemoglobin (HGB) <= 10 g/dl and TLC<= 1200/mcL at baseline were not associated with increased mortality. Body mass index (BMI) <= 18.5 kg/m2 at baseline was associated with death in univariate analysis. Weight loss was seen in about a third of patients who survived up to the fourth week, and it was associated with increased death. Decline in TLC, HGB and BMI was associated with death in univariate analysis only. CONCLUSION: The high mortality rate seen in this cohort was associated with advanced disease stage and very low TLC at presentation. Patients should be identified and treated before they progress to advanced stages. The underlying causes for early death in patients presenting at late stages should be investigated

IL-12 and GM-CSF in DNA/MVA Immunizations against HIV-1 CRF12_BF Nef Induced T-Cell Responses With an Enhanced Magnitude, Breadth and Quality

In Argentina, the HIV epidemic is characterized by the co-circulation of subtype B and BF recombinant viral variants. Nef is an HIV protein highly variable among subtypes, making it a good tool to study the impact of HIV variability in the vaccine design setting. We have previously reported a specific cellular response against NefBF with low cross-reactivity to NefB in mice. The aim of this work was to analyze whether the co-administration of IL-12 and GM-CSF, using DNA and MVA vaccine vectors, could improve the final cellular response induced. Mice received three DNA priming doses of a plasmid that express NefBF plus DNAs expressing IL-12 and/or GM-CSF. Afterwards, all the groups were boosted with a MVAnefBF dose. The highest increase in the magnitude of the NefBF response, compared to that induced in the control was found in the IL-12 group. Importantly, a response with higher breadth was detected in groups which received IL-12 or GM-CSF, evidenced as an increased frequency of recognition of homologous (BF) and heterologous (B) Nef peptides, as well as a higher number of other Nef peptide pools representing different viral subtypes. However, these improvements were lost when both DNA cytokines were simultaneously administered, as the response was focused against the immunodominant peptide with a detrimental response towards subdominant epitopes. The pattern of cytokines secreted and the specific-T-cell proliferative capacity were improved in IL-12 and IL-12+GM-CSF groups. Importantly IL-12 generated a significant higher T-cell avidity against a B heterologous peptide

Co-infection by human immunodeficiency virus type 1 (HIV-1) and human T cell leukemia virus type 1 (HTLV-1): does immune activation lead to a faster progression to AIDS?

<p>Abstract</p> <p>Background</p> <p>Recent data have shown that HTLV-1 is prevalent among HIV positive patients in Mozambique, although the impact of HTLV-1 infection on HIV disease progression remains controversial. Our aim was to determine the phenotypic profile of T lymphocytes subsets among Mozambican patients co-infected by HIV and HTLV-1.</p> <p>Methods</p> <p>We enrolled 29 patients co-infected by HTLV-1 and HIV (co-infected), 59 patients mono-infected by HIV (HIV) and 16 healthy controls (HC), respectively.</p> <p>For phenotypic analysis, cells were stained with the following fluorochrome-labeled anti-human monoclonal antibodies CD4-APC, CD8-PerCP, CD25-PE, CD62L-FITC, CD45RA-FITC. CD45RO-PE, CD38-PE; being analysed by four-colour flow cytometry.</p> <p>Results</p> <p>We initially found that CD4⁺T cell counts were significantly higher in co-infected, as compared to HIV groups. Moreover, CD4⁺T Lymphocytes from co-infected patients presented significantly higher levels of CD45RO and CD25, but lower levels of CD45RA and CD62L, strongly indicating that CD4⁺T cells are more activated under HTLV-1 plus HIV co-infection.</p> <p>Conclusion</p> <p>Our data indicate that HTLV-1/HIV co-infected patients progress with higher CD4⁺T cell counts and higher levels of activation markers. In this context, it is conceivable that in co-infected individuals, these higher levels of activation may account for a faster progression to AIDS.</p

Could bats act as reservoir hosts for Rift Valley fever virus?

The inter-epizootic reservoir host of Rift Valley fever virus (RVFV) remains unknown, although the namaqua rock rat, Aethomys namaquensis, as well as bats have been implicated. Bats can be asymptomatically infected with rabies, as well as several arboviruses; the possibility that they can act as host for RVFV therefore exists. To examine this possibility, 350 different samples (brain, liver, salivary glands and brown fat) obtained from 150 bats (comprising seven species) were tested for RVFV antigen using an enzyme linked immunosorbent assay (ELISA). None of the samples tested positive, but the ELISA proved to have limited sensitivity (≥103 TCID50/ml). In order to determine whether bats could be infected with RVFV, one Miniopterus schreibersii and two Eptesicus capensis bats were inoculated by the oral or intramuscular route with 100 ml and 30 ml, respectively, of a RVFV suspension with a titre of 106 TCID50/ml. None of the bats developed any clinical signs. A low concentration of RVFV antigen was found in the liver and urine of M. schreibersii, but not in brain tissue. A third E. capensis bat was inoculated by the intramuscular route and sacrificed on day 18. A low level of antigen was detected in the brown fat. These results demonstrate that bats can be infected with RVFV, and that further studies should be done to determine the potential of different bat species to act as reservoir hosts for RVFV during inter-epizootic periods.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat v.9 was used to OCR the text and also for the merging and conversion to the final presentation PDF-format