Christopher J. Seebregts

Persistent Microbial Translocation and Immune Activation in HIV-1-Infected South Africans Receiving Combination Antiretroviral Therapy

BACKGROUND Microbial translocation contributes to immune activation and disease progression during chronic human immunodeficiency virus type 1 (HIV-1) infection. However, its role in the African AIDS epidemic remains controversial. Here, we investigated the relationship between markers of monocyte activation, plasma lipopolysaccharide (LPS), and HIV-1 RNA in South Africans prioritized to receive combination antiretroviral therapy (cART). METHODS Ten HIV-1-negative African controls and 80 HIV-1-infected patients with CD4 T cell counts <200 cells/microL were sampled prior to (n=60) or during (n=20) receipt of effective cART. Viral load was measured by Nuclisens; LPS by the Limulus amoebocyte lysate assay; monocyte and T cell subsets by flow cytometry; and soluble CD14, cytokines, and chemokines by enzyme-linked immunosorbent assay and customized Bio-Plex plates. RESULTS Three distinct sets of markers were identified. CCL2, CXCL10, and CD14(+)CD16(+) monocyte levels were positively correlated with HIV-1 viremia. This finding, together with cART-induced normalization of these markers, suggests that their upregulation was driven by HIV-1. Plasma interleukin-6 was associated with the presence of opportunistic coinfections. Soluble CD14 and tumor necrosis factor were linked to plasma LPS levels and, as observed for LPS, remained elevated in patients receiving effective cART. CONCLUSIONS Microbial translocation is a major force driving chronic inflammation in HIV-infected Africans receiving cART. Prevention of monocyte activation may be especially effective at enhancing therapeutic outcomes.

The OpenMRS Implementers Network

OBJECTIVE OpenMRS (www.openmrs.org) is a configurable open source electronic medical record application developed and maintained by a large network of open source developers coordinated by the Regenstrief Institute and Partners in Health and mainly used for HIV patient and treatment information management in Africa. Our objective is to develop an open Implementers Network for OpenMRS to provide regional support for the growing number of OpenMRS implementations in Africa and to include African developers and implementers in the future growth of OpenMRS. METHODS We have developed the OpenMRS Implementers Network using a dedicated Wiki site and e-mail server. We have also organized annual meetings in South Africa and regional training courses at African locations where OpenMRS is being implemented. An OpenMRS Internship program has been initiated and we have started collaborating with similar networks and projects working in Africa. To evaluate its potential, OpenMRS was implemented initially at one site in South Africa by a single implementer using a downloadable OpenMRS application and only the OpenMRS Implementers Network for support. RESULTS The OpenMRS Implementers Network Wiki and list server have grown into effective means of providing implementation support and forums for exchange of implementation experiences. The annual OpenMRS Implementers meeting has been held in South Africa for the past three years and is attracting successively larger numbers of participants with almost 200 implementers and developers attending the 2008 meeting in Durban, South Africa. Six African developers are presently registered on the first intake of the OpenMRS Internship program. Successful collaborations have been started with several African developer groups and projects initiated to develop interoperability between OpenMRS and various applications. The South African OpenMRS Implementer group successfully configured, installed and maintained an integrated HIV/TB OpenMRS application without significant programming support. Since then, this model has been replicated in several other African sites. The OpenMRS Implementers Network has contributed substantially to the growth and sustainability of OpenMRS in Africa and has become a useful way of including Africans in the development and implementation of OpenMRS in developing countries. The Network provides valuable support and enables a basic OpenMRS application to be implemented in the absence of onsite programmers.

Handheld computers for survey and trial data collection in resource-poor settings: Development and evaluation of PDACT, a Palm™ Pilot interviewing system

OBJECTIVE Handheld computers (personal digital assistant, PDA) have the potential to reduce the logistic burden, cost, and error rate of paper-based health research data collection, but there is a lack of appropriate software. The present work describes the development and evaluation of PDACT, a Personal Data Collection Toolset (www.healthware.org/pdact/index.htm) for the Palm Pilot handheld computer for interviewer-administered and respondent-administered data collection. METHODS We developed Personal Data Collection Toolkit (PDACT) software to enable questionnaires developed in QDS Design Studio, a Windows application, to be compiled and completed on Palm Pilot devices and evaluated in several representative field survey settings. RESULTS The software has been used in seven separate studies and in over 90,000 interviews. Five interviewer-administered studies were completed in rural settings with poor communications infrastructure, following one day of interviewer training. Two respondent-administered questionnaire studies were completed by learners, in urban secondary schools, after 15min training. Questionnaires were available on each handheld in up to 11 languages, ranged from 20 to 580 questions, and took between 15 and 90min to complete. Up to 200 Palm Pilot devices were in use on a single day and, in about 50 device-years of use, very few technical problems were found. Compared with paper-based collection, data validation and cleaning times were reduced, and fewer errors were found. PDA data collection is easy to use and preferred by interviewers and respondents (both respondent-administered and interviewer-administered) over paper. Data are compiled and available within hours of collection facilitating data quality assurance. Although hardware increases the setup cost of the first study, the cumulative cost falls thereafter, and converges on the cumulative cost of paper-based studies (four, in the case of our interviewer-administered studies). Handheld data collection is an appropriate, affordable and convenient technology for health data collection, in diverse settings.

Public database for HIV drug resistance in southern Africa

The Opinion article by S. Karim and Q. Karim laments the lack of an effective conduit between South Africa’s AIDS research and its prevention and treatment policies and programmes (Nature 463, 733–734; 2010). We would like to draw attention to an HIV-1 drug-resistance database, a scientific resource for regional and global HIV research that will enhance surveillance programmes in southern Africa.

Circulating biomarkers of immune activation distinguish viral suppression from nonsuppression in HAART-treated patients with advanced HIV-1 subtype C infection.

Few studies have examined immune activation profiles in patients with advanced HIV-1 subtype C infection or assessed their potential to predict responsiveness to HAART. BioPlex, ELISA, and nephelometric procedures were used to measure plasma levels of inflammatory biomarkers in HIV-1 subtype C-infected patients sampled before and after 6 months of successful HAART (n = 20); in patients failing HAART (n = 30); and in uninfected controls (n = 8). Prior to HAART, CXCL9, CXCL10, β2M, sTNF-R1, TGF-β1, IFN-γ, IL-6, TNF, and sCD14 were significantly elevated in HIV-1-infected patients compared to controls (P < 0.01). All of these markers, with the exception of sTNF-R1, were also elevated in patients failing HAART (P < 0.05). The persistently elevated levels of CXCL9, CXCL10, and β2M in patients failing therapy in the setting of a marked reduction in these markers in patients on successful HAART suggest that they may be useful not only to monitor immune activation during HAART, but also to distinguish between good and poor responders. In the case of sCD14 and TGF-β1, the levels of these biomarkers remained persistently elevated despite HAART-induced virological suppression, a finding that is consistent with ongoing monocyte-macrophage activation, underscoring a potential role for adjuvant anti-inflammatory therapy.

An Affordable HIV-1 Drug Resistance Monitoring Method for Resource Limited Settings

HIV-1 drug resistance has the potential to seriously compromise the effectiveness and impact of antiretroviral therapy (ART). As ART programs in sub-Saharan Africa continue to expand, individuals on ART should be closely monitored for the emergence of drug resistance. Surveillance of transmitted drug resistance to track transmission of viral strains already resistant to ART is also critical. Unfortunately, drug resistance testing is still not readily accessible in resource limited settings, because genotyping is expensive and requires sophisticated laboratory and data management infrastructure. An open access genotypic drug resistance monitoring method to manage individuals and assess transmitted drug resistance is described. The method uses free open source software for the interpretation of drug resistance patterns and the generation of individual patient reports. The genotyping protocol has an amplification rate of greater than 95% for plasma samples with a viral load >1,000 HIV-1 RNA copies/ml. The sensitivity decreases significantly for viral loads <1,000 HIV-1 RNA copies/ml. The method described here was validated against a method of HIV-1 drug resistance testing approved by the United States Food and Drug Administration (FDA), the Viroseq genotyping method. Limitations of the method described here include the fact that it is not automated and that it also failed to amplify the circulating recombinant form CRF02_AG from a validation panel of samples, although it amplified subtypes A and B from the same panel.

Position paper: researching and developing open architectures for national health information systems in developing african countries

Most African countries have limited health information systems infrastructure. Some health information system components are implemented but often on an adhoc, piecemeal basis, by foreign software developers and designed to solve specific problems. Little attention is usually paid to how these components can fit into an integrated national health information system and interoperate with other components. The Health Enterprise Architecture Laboratory was recently established in the School of Computer Science at the University of KwaZulu-Natal in South Africa to undertake research and build capacity in open health architectures for developing African countries. Based on field experiences and requirements in South Africa, Mozambique and Rwanda, the laboratory is evolving a generic Health Enterprise Architecture Framework and Repository of Tools specifically for low resource settings. In this paper we describe these three initiatives and the expected impact on implementing health information systems in developing African countries.

CD14 + macrophages that accumulate in the colon of African AIDS patients express pro-inflammatory cytokines and are responsive to lipopolysaccharide

BackgroundIntestinal macrophages are key regulators of inflammatory responses to the gut microbiome and play a central role in maintaining tissue homeostasis and epithelial integrity. However, little is known about the role of these cells in HIV infection, a disease fuelled by intestinal inflammation, a loss of epithelial barrier function and increased microbial translocation (MT).MethodsPhenotypic and functional characterization of intestinal macrophages was performed for 23 African AIDS patients with chronic diarrhea and/or weight loss and 11 HIV-negative Africans with and without inflammatory bowel disease (IBD). AIDS patients were treated with cotrimoxazole for the prevention of opportunistic infections (OIs). Macrophage phenotype was assessed by flow cytometry and immuno-histochemistry (IHC); production of proinflammatory mediators by IHC and Qiagen PCR Arrays; in vitro secretion of cytokines by the Bio-Plex Suspension Array System. Statistical analyses were performed using Spearman’s correlation and Wilcoxon matched-pair tests. Results between groups were analyzed using the Kruskal-Wallis with Dunn’s post-test and the Mann–Whitney U tests.ResultsNone of the study participants had evidence of enteric co-infections as assessed by stool analysis and histology. Compared to healthy HIV-negative controls, the colon of AIDS patients was highly inflamed with increased infiltration of inflammatory cells and increased mRNA expression of proinflammatory cytokine (tumour necrosis factor (TNF)-α, interleukin (IL)-1β, IFN-γ, and IL-18), chemokines (chemokine (C-C motif) ligand (CCL)2 and chemokine (C-X-C) motif ligand (CXCL)10) and transcription factors (TNF receptor-associated factor (TRAF)6 and T-box (TXB)21). IHC revealed significant co-localization of TNF-α and IL-1β with CD68+ cells. As in IBD, HIV was associated with a marked increase in macrophages expressing innate response receptors including CD14, the co-receptor for lipopolysaccharide (LPS). The frequency of CD14+ macrophages correlated positively with plasma LPS, a marker of MT. Total unfractionated mucosal mononuclear cells (MMC) isolated from the colon of AIDS patients, but not MMC depleted of CD14+ cells, secreted increased levels of proinflammatory cytokines ex vivo in response to LPS.ConclusionsIntestinal macrophages, in the absence of overt OIs, play an important role in driving persistent inflammation in HIV patients with late-stage disease and diarrhea. These results suggest intensified treatment strategies that target inflammatory processes in intestinal macrophages may be highly beneficial in restoring the epithelial barrier and limiting MT in HIV-infected patients.

An Architecture and Reference Implementation of an Open Health Information Mediator: Enabling Interoperability in the Rwandan Health Information Exchange

Rwanda, one of the smallest and most densely populated countries in Africa, has made rapid and substantial progress towards designing and deploying a national health information system. One of the more challenging aspects of the system is the design of an architecture to support: interoperability between existing health information systems already in use in the country; incremental extension into a fully integrated national health information system without substantial re-engineering; and scaling, from a single district in the initial phase, to national level without requiring a fundamental change in technology or design paradigm. This paper describes the key requirements and the design of the current architecture using the ISO/IEC/IEEE 42010 standard architecture descriptions. The architecture takes an Enterprise Service Bus approach. A partial implementation and preliminary analysis of the architecture is given. Since these challenges are experienced by other developing African countries, the next steps involves creating a generic architecture that can be reused for health information exchange in other developing African countries.

Southern African Treatment Resistance Network (SATuRN) RegaDB HIV drug resistance and clinical management database: supporting patient management, surveillance and research in southern Africa

Abstract Substantial amounts of data have been generated from patient management and academic exercises designed to better understand the human immunodeficiency virus (HIV) epidemic and design interventions to control it. A number of specialized databases have been designed to manage huge data sets from HIV cohort, vaccine, host genomic and drug resistance studies. Besides databases from cohort studies, most of the online databases contain limited curated data and are thus sequence repositories. HIV drug resistance has been shown to have a great potential to derail the progress made thus far through antiretroviral therapy. Thus, a lot of resources have been invested in generating drug resistance data for patient management and surveillance purposes. Unfortunately, most of the data currently available relate to subtype B even though >60% of the epidemic is caused by HIV-1 subtype C. A consortium of clinicians, scientists, public health experts and policy markers working in southern Africa came together and formed a network, the Southern African Treatment and Resistance Network (SATuRN), with the aim of increasing curated HIV-1 subtype C and tuberculosis drug resistance data. This article describes the HIV-1 data curation process using the SATuRN Rega database. The data curation is a manual and time-consuming process done by clinical, laboratory and data curation specialists. Access to the highly curated data sets is through applications that are reviewed by the SATuRN executive committee. Examples of research outputs from the analysis of the curated data include trends in the level of transmitted drug resistance in South Africa, analysis of the levels of acquired resistance among patients failing therapy and factors associated with the absence of genotypic evidence of drug resistance among patients failing therapy. All these studies have been important for informing first- and second-line therapy. This database is a free password-protected open source database available on www.bioafrica.net. Database URL: http://www.bioafrica.net/regadb/