Please Sign In or Create an account
Investigation of immune markers that may explain association of CMV antibody titres and cardiovascular risk in HIV+ individuals stable on HAART

Investigation of immune markers that may explain association of CMV antibody titres and cardiovascular risk in HIV+ individuals stable on HAART

HIV patients stable on HAART have both high plasma cytomegalovirus (CMV) antibody titres and increased risk of cardiovascular disease (CVD), parameters that correlate in healthy persons. We examined the contribution of immune activation and autoimmunity to this correlation in HIV+ individuals stable on HAART.

Plasma samples from 70 HIV+ individuals stable on HAART for 14(2-29) years and 120 age-matched healthy controls were assayed for total immunoglobulin G (IgG) reactive with CMV, human fibroblasts, HIVgp41, cardiolipin and immunoglobulins (GAM) reactive to heterologous smooth muscle. A correlation between anti-cardiolipin and anti-HIVgp41 antibodies was sought as evidence for cross reactivity. Samples from HIV+ individuals were further assayed for the immune activation markers sCD40L, sCX3CL1 and sTNFR. Patients attended clinic at St Vincent’s Hospital, Darlinghurst NSW. Clinical data were compiled and Framingham scores calculated to assess of risk of CVD.

CMV antibody titres correlated with Framingham scores (p=0.009, Spearman R=0.317). Nadir CD4 T-cell counts displayed a strong inverse relationship with CMV antibody (p=0.0004, Spearman R=-0.42). A multivariate model identified nadir CD4 T-cell count, Framingham score, total IgG, sCD40L and sCX3CL1 as factors associating with levels of CMV antibody. There was no association with sTNFR. Preliminary data suggests HIV patients have higher levels of CMV antibody and a higher incidence of anti-smooth muscle antibody than healthy controls. Anti-smooth muscle antibody levels correlated with total IgG and anti-CMV pp65 in HIV+ individuals. The incidence of anti-cardiolipin antibodies was higher in HIV patients than healthy controls.

Elevation of CMV antibodies in HIV patients is not a simple consequence of generalised immune activation but may reflect high antigenic load before HAART. Anti-smooth muscle antibodies show a strong relationship with B-cell activation as measured by total IgG. Associations between CMV, autoimmunity and CVD are being investigated further.

Speakers: Samantha Brunt
Conference: ASHM 2013

Australian Society for HIV 2013

Delayed HIV diagnoses among gay and bisexual men in Australia

The majority of HIV diagnoses including delayed diagnoses in Australia occur among men who report homosexual contact – hereafter called gay and bisexual men (GBM). Delayed diagnosis is strongly associated with increased HIV-related mortality and morbidity. People who are unaware of their HIV-positive status may also be unwittingly transmitting HIV. We assessed trends in delayed HIV diagnoses among GBM in Australia.

Complex case report that illustrates the paucity of data for long term management of Visceral Leishmania-HIV co-infection.

HIV-associated leishmaniasis, endemic in the Mediterranean basin is a growing problem in India, Brazil and East Africa. Despite surviving for than 20 years, the clinical course of our visceral-leishmania (VL)-HIV co-infected patient illustrates several management challenges including diagnosis, speciation and drug resistance; monitoring burden of disease; access to and use of VL-treatments; end-organ toxicity and the combined immunosuppressive effects of HIV-VL.

Clinical factors associated with suboptimal adherence to antiretroviral therapy in Asia

Adherence to combination antiretroviral therapy (cART ) plays an important role on treatment outcomes. The TREAT Asia Studies to Evaluate Resistance – Monitoring Cohort Study (TASER-M) collects patients’ adherence based on a Visual Analogue Scale. The aim of this analysis was to assess the rates of, and factors associated with, suboptimal adherence in the first 24 months of initial cART in Asian patients.

Reinvigorating evidence for action and capacity in community HIV programs (REACH Project)

REACH was a collaborative research and practice initiative to develop evidence building frameworks, capacity, tools and resources with the Victorian HIV community partnership.

The impact of immune activation on natural killer cells in the setting of HIV infection

HIV disease is associated with chronic inflammation and activation of the innate immune system. This state, as measured using plasma markers of inflammation, persists following suppression of HIV viremia using antiretroviral therapy, and may increase risk of non-AIDS co-morbidities. The causes of innate immune activation in the setting of virological suppression are unclear. Natural killer (NK) cells are innate immune cells that kill virus-infected and transformed cells without prior sensitization. We have shown that NK cells are activated both phenotypically (elevated expression of HLA-DR) and functionally (increased spontaneous degranulation measured by CD107a surface expression) in virologically suppressed (VS) HIV+ individuals. NK cells also lose expression of CD16, the receptor which mediates antibody-dependent cellular cytotoxicity.

Men who take more risks avoid HIV testing due to structural barriers

Regular HIV testing is recommended in men who take sexual risks. We assessed the relationship between perceived barriers to HIV testing, and frequency of testing among men who engaged in unprotected anal intercourse with casual partners (UAIC), to inform HIV testing strategies.

A dramatic increase in the use of mobile apps to meet partners among gay men in Melbourne and Sydney is not associated with increased risk-taking: findings from the Gay Community Periodic Surveys, 2010-2013

In recent years there has been a widespread uptake of smartphones with internet access and location services and the development of mobile ‘apps’ for gay men to meet each other. We reviewed data collected in the Sydney and Melbourne Gay Community Periodic Surveys (GCPS) to identify which men were relying on mobile and internet methods to meet each other and whether these methods were associated with different risk practices.