Human immuno deficiency virus (HIV) incorporates host cellular protein, beta-2-microglobulin (β2m), into its surface envelope during budding. β2m is a cellular protein that belongs to the major histocompatibility complex (MHC) Class I molecules. Studies have shown anti- β2m monoclonal antibodies (mAbs) has the ability of to neutralize the virus. An epitope consisting of seven amino acids of the β2m protein designated as R7V produces antibodies that protect HIV infected people from progressing to AIDS. These protective antibodies, called anti-R7V antibodies, were able to neutralize different HIV isolates, despite their genomic variations, various cellular targets and geographic origin. Anti-R7V antibodies in the format of single chain variable fragments (scFvs) were produced in our laboratory using the M13 phage display technology. These scFv antibody fragments were used during in vitro studies for the detection and neutralization of the R7V antigen by enzyme linked immune sorbent assay (ELISA). The scFv fragments produced against the R7V epitope showed interaction, however the antibody-antigen affinity was too weak for the virus neutralization assay. Hence, this project focused on the affinity maturation of the anti-R7V scFv fragments through random mutagenesis using the error prone (EP) PCR method. The EP PCR method generated two mutated anti-R7V scFvs. The mutated clones were subcloned into the pAK400 expression vector. The computer-based models, created using the Swiss PDB Deep Viewer 4.02 software, were used to predict the antigen-binding site and affinity analysis of both parent and mutated scFv’s. Mutated clone 1 failed to bind to the R7V epitope whereas mutated clone 2 had similar binding pattern as the parent scFv. Mutated clone 2 was predicted to have a higher binding affinity compared to the parent scFv. The results obtained demonstrate the efficacy of EP PCR to generate high affinity antibodies. Future experiments using high affinity anti-R7V scFv’s may lead to its potential use in diagnostics, therapeutics or vaccine development. Copyright / Dissertation (MSc)--University of Pretoria, 2012. / Biochemistry / unrestricted

Indiana University-Purdue University Indianapolis (IUPUI) / While insomnia/sleep disturbance has been identified as an independent predictor of cardiovascular disease in the general population, no studies have examined whether insomnia contributes to the elevated cardiovascular disease (CVD) risk in people with human immunodeficiency virus (HIV). Thus, the current study examined whether insomnia symptoms predict incident atherosclerotic CVD in the Veterans Aging Cohort Study 9 (VACS9), a prospective cohort of HIV-infected (n = 3,138) and uninfected (n = 3,010) Veterans utilizing self-report measures and administrative data. In partial support of my hypotheses, I found that HIV-infected Veterans bothered a lot by difficulty falling or staying asleep have greater CVD risk than HIV-infected Veterans without these symptoms. This study failed to replicate previous findings that insomnia symptoms are predictive of incident CVD in uninfected adults, which may be due to issues related to the validity of the insomnia symptoms assessment. A number of methodological issues are identified and considered in the interpretation of the current study results. Given the novelty of examining insomnia as a predictor of incident CVD in HIV-infected adults and the limitations of the present study, future research is needed to better elucidate the association between insomnia and future CVD in this population.

Introduction: Improvements in early detection of human immunodeficiency virus (HIV), linkage to treatment, and availability of antiretroviral therapy (ART) have contributed to increasing life expectancy for people living with HIV (PLHIV) in South Africa. These improvements have resulted in the decline of HIV cause-specific mortalities. In addition to existing tuberculosis burden in PLHIV, cases of chronic non-communicable diseases (NCDs) are increasing in the general population. Considering the ageing population of PLHIV in South Africa, it is important to understand their health needs, as well as identify potential drivers of comorbidities that may provide avenues for future interventions. This study aimed at exploring HIV and comorbidity profiles in a virtual cohort of a population of healthcare clients accessing care in public facilities in Khayelitsha, Cape Town. Methods: Routinely collected data for healthcare clients accessing care in public facilities in 2016/17 were obtained from the Western Cape Provincial Health Data Centre, and analysed to describe ascertained comorbidities, comparing the profiles of PLHIV and HIV-negative individuals. The risks of comorbidity occurrence in PLHIV, in the context of other comorbidities and HIV metrics such as ART duration, viral load and CD4 cell counts, including the contribution of comorbidities to unsuppressed viral load levels in PLHIV were explored. Findings: The findings show that accessing HIV care may lead to earlier ascertainment of common chronic NCDs – hypertension, diabetes, chronic kidney disease (CKD), cervical cancer in PLHIV, compared to HIV-negative clients. Analysis of routine health data suggests that ascertainment of comorbidities differs for healthcare clients due to sub-population differences including age, sex, HIV status and reasons for accessing care. Routine laboratory testing results for renal function reflect distinct healthcare experiences by age for healthcare clients with and without HIV. Analysis of routine data shows that presence of an existing comorbidity may contribute to the incidence of other comorbidities and unsuppressed viral load levels in PLHIV. Conclusion: From real life routine health data, this study has explored comorbidities profiles of PLHIV and HIV-negative clients and observed that routine health data could provide a better understanding of disease profiles, healthcare access and requirements for both PLHIV and HIV-negative clients.

No description available.

Women face a number of physical, emotional and psychological challenges following an HIV positive diagnosis during pregnancy. Psychological challenges, such as maternal anxiety and low mood, have been associated with disruptions to mother-infant bonding in the general population. Despite significant numbers of women receiving an antenatal HIV diagnosis in the UK each year, there remains a limited understanding about the experiences of this group in bonding with their babies. This Grounded Theory study aimed to explore the experience of mothers in bonding with their baby following an HIV diagnosis during pregnancy. The study explored the perceived challenges to mother-infant bonding, and the factors mothers felt helped them to manage this process following diagnosis. Ten mothers diagnosed antenatally at a London sexual health service were interviewed about their experiences. Data analysis led to a theoretical model of mother-infant bonding following a maternal HIV positive maternal diagnosis. The model comprised four theoretical codes: facing barriers to bonding; feeling disconnected from the baby; developing a special bond; and strengthening and moving on. These codes were comprised of challenges to mother-infant bonding, as well as factors relating to maternal strength and resilience. The model used a chronological structure, with processes plotted from the point of antenatal diagnosis through to following the infant HIV testing process after birth. Challenges with bonding were experienced primarily during the early stages after birth, with maternal resilience and positivity about the future developing towards the end of infant testing. Circular relationships, in which positive and negative processes fed into and influenced each other, were highlighted throughout. The findings highlight important areas for development in clinical practice, including more targeted psychological support for women following an antenatal diagnosis, and the provision of timely information regarding mother-to-child transmission. Clinical implications from this study are discussed alongside suggestions for future research.

Student Number : 8403267 - PhD thesis - School of Pathology - Faculty of Health Sciences / Sub-Saharan Africa is the eye of the HIV epidemic. This study was conducted when treatment for the majority of HIV-infected patients in low resource settings was considered unattainable and the risks of diagnosing HIV often outweighed the benefits. Coupled with the complexities of HIV diagnosis in infancy, children typically were only diagnosed once already ill or not at all. Key strategies to address the paediatric epidemic focused on preventing mother to child transmission and reducing mortality and morbidity of infected children predominantly with co-trimoxazole prophylaxis. Both strategies required early diagnosis of HIV infection in infancy for monitoring prevention programs and identifying infected children respectively. The diagnostic algorithm for resource limited settings recommended the use of inexpensive, technically simpler HIV antibody detection assays that are unsuitable for use in HIV-exposed children under 12-months of age. Paradoxically this algorithm provided a barrier to HIV diagnosis in children because of high loss to follow-up rates and death in the first year of life. The objective of this study was to establish an accurate, affordable diagnostic algorithm for early diagnosis of HIV infection that could be rapidly implemented in South Africa and benefit other resource limited settings. The HIV infection status of 300 vertically exposed infants was determined according to first world criteria in a prospective, cohort study at Coronation Hospital, Johannesburg over 21 months. This status was used to assess the accuracy of clinical examinations and HIV assays in diagnosing HIV at 6-weeks, 3-, 7- and 12-months of age. The average cost of determining an infant’s HIV infection status was measured. A single HIV DNA PCR test at 6-weeks of age proved highly accurate in determining HIV status at a marginally increased cost to government and was incorporated by the South African Department of Health into national policy. The ultrasensitive p24 antigen assay and HIV antibody detection assays on serum and oral fluid were identified as valuable candidates where PCR testing is unavailable. Dried blood spot samples from heelpricks are critical for policy to be translated into practice since skills to perform venesection in 6-week old babies are limited. The next challenge lies in operationalising these findings at a clinical and laboratory level to the benefit of the 300 000 South African children annually exposed to HIV at birth. The urgency of early diagnosis has been increased by the availability of highly effective antiretroviral therapy.

Student Number : 9813645X - PhD thesis - Faculty of Health Sciences / Epidemiological information on sexually transmitted infections (STIs) is necessary to assess the magnitude of the burden of infections, to identify vulnerable population groups, to mobilise resources for intervention activities and to monitor the impact of these activities. In addition, specific STI surveillance systems, such as studies on the relative prevalence of aetiological agents of STI syndromes and their antimicrobial susceptibility patterns, are aimed at improving patient care. The studies included in this thesis were designed and implemented to improve our understanding of the epidemiology of STIs and HIV infection in southern Africa. In all the study populations, we observed that high level STI epidemics preceded the explosive spread of HIV infection among high-risk individuals. The studies reported here also demonstrate the importance of triangulating data collected from different recommended STI surveillance components, using a tiered surveillance approach. The studies reported here also explored the bidirectional interactions of HIV and STIs. We observed that different STIs have shown different magnitudes of interaction with HIV infection. We found particularly strong interactions between genital herpes and HIV. At the individual level, HIV-seropositive patients with genital herpes were more frequently found to have atypical clinical presentations, delays in spontaneous healing, longer duration of HSV shedding and increased association with HIV shedding from ulcer and genital exudates. Mixed infections involving chancroid and genital herpes were found to be common, particularly in HIV-seropositive patients. The effectiveness of syndromic treatment targeting only bacterial causes of genital ulceration was significantly reduced due to persistent ulcerations as a result of co-infection with genital herpes. The successful treatment of herpes in men and women was found to be associated with a decline or cessation in HIV shedding into ulcer exudates or genital fluid. The studies have also shown that HIV plasma viral load is the main determinant for HIV shedding in both men and women presenting with STIs. As was the case with HSV infection, there was a strong association between HIV and HPV infection in both men and women. A higher prevalence of HPV infection was found among HIV-seropositive patients in our study population and this may reflect the higher frequency of recurrences and/or longer duration of infection (i.e. persistency). The studies also found that the biological false positive reactions in syphilis serology (i.e. RPR) are not a common occurrence in our HIV-seropositive study population. On the other hand, syphilis serology could be falsely negative in patients with PCR-confirmed primary syphilis who are co-infected with HIV and other aetiological agents causing GUD. In conclusion, the findings of our studies have supported the bidirectional nature of interactions between conventional STIs and HIV infection in southern Africa.

This researched aimed to explore the effects of the Human Immunodeficiency Virus (HIV) upon the visuospatial abilities of HIV-positive adolescents on antiretroviral treatment in South Africa. The literature suggests that the neurology responsible for visuospatial abilities (specifically various white-matter tracts in the brain) is very susceptible to the damaging effect that HIV has on the brain. The research sample consisted of vertically transmitted HIV-positive adolescents, on first line antiretroviral treatment, with a HIV-negative control group comparable on age and SES. The results indicated that there is a significant difference in the visuospatial abilities between adolescents with and without HIV. The expressions of these deficits were displayed differently between males and females, highlighting a differing developmental neurology, and the effect of HIV upon it. The viral strength and health of the immune system were also examined as variables and illuminated interesting results. Overall, the research illustrates the negative effect that HIV has upon developing neurology and the subsequent effects on visuospatial abilities.

Philosophiae Doctor - PhD / Tuberculosis (TB) is an infectious disease with adverse effect on a global scale. The disease is one of the major causes of death in sub-Saharan Africa. Nearly 70% of TB-infected persons are co-infected by the human immunodeficiency virus (HIV). About 50% of TB/HIV patients are smear negative and up to 28% are sputum scarce, which is a significant problem in South Africa since sputum smear microscopy is the most widely used diagnostic test for TB. The detection of Mycobacterium tuberculosis (MTB) and resistance to the TB drug rifampicin (RIF) are the basis of the GeneXpert MTB/RIF protocol. The GeneXpert MTB/RIF is an automated nucleic acid amplification technique for detecting the DNA that originates from MTB. However, low sensitivity and low concentrations of MTB for DNA amplification are a serious issue associated with the protocol. Therefore, other TB diagnostic methods, such as the ones involving biochemical markers of TB, are becoming very important. / 2020-08-31

Human Immunodeficiency Virus Type I, or HIV, is one of the most well-known and well-researched viruses in the world. The current standard of care for HIV infected individuals is an antiretroviral drug therapy regiment, or ART, started immediately after diagnosis. While this treatment is generally quite effective at keeping the viral load low and stopping the progression from HIV infection to AIDS, patients receiving ART therapy still have a lower life expectancy than uninfected individuals. Many times, the cause of death in these patients is not the common opportunistic pathogens and cancers linked to HIV and AIDS, but chronic health conditions that develop. One of these conditions that is seen in many of the HIV infected patients undergoing the antiretroviral therapy is cardiovascular disease, such as atherosclerosis and myocardial infarction. Research shows that one of the key players in developing these conditions in HIV patients is the chronic inflammation caused by the immune system attempts to control the level of the virus. By studying the links between HIV, inflammation, and cardiovascular disease, we may be able to find solutions to the development of chronic disease in HIV patients on antiretroviral therapy.