The role of T cells in the development of cardiovascular disease in HIV-infected patients

Cardiovascular Risk Assessment Among Adolescents and Youths Living With HIV: Evaluation of Electronic Health Record Findings and Implications

BACKGROUND

The HIV epidemic remains a major public health concern, particularly among youths living with HIV. While the availability of antiretroviral therapy has significantly improved the health outcomes of people living with HIV, there is growing evidence that youths living with HIV may be at increased risk of cardiovascular disease. However, the underlying mechanisms linking HIV and cardiovascular disease among youths living with HIV remain poorly understood. One potential explanation is that HIV-related biomarkers, including detectable viral load (VL) and low cluster of differentiation 4 (CD4) lymphocyte counts, may contribute to increased cardiovascular risk. Despite the potential importance of these biomarkers, the relationship between HIV-related biomarkers and cardiovascular risk among youths living with HIV has been understudied.

OBJECTIVE

To address this gap, we examined whether detectable VL and low CD4 lymphocyte counts, both of which are indications of unsuppressed HIV, were associated with cardiovascular risk among youths living with HIV.

METHODS

We analyzed electronic health record data from 7 adolescent HIV clinics in the United States (813 youths living with HIV). We used multivariable linear regression to examine the relationship between detectable VL and CD4 lymphocyte counts of ≤200 and cardiovascular risk scores, which were adapted from the gender-specific Framingham algorithm.

RESULTS

In our study, nearly half of the participants (366/766, 47.8%) had detectable VL, indicating unsuppressed HIV, while 8.6% (51/593) of them had CD4 lymphocyte counts of ≤200, suggesting weakened immune function. We found that those with CD4 lymphocyte counts of ≤200 had significantly higher cardiovascular risk, as assessed by Cardiac Risk Score2, than those with CD4 lymphocyte counts of >200 (P=.002). After adjusting for demographic and clinical factors, we found that for every 1000-point increase in VL copies/mL, the probability of having cardiovascular risk (Cardiac Risk Score2) increased by 38%. When measuring the strength of this connection, we observed a minor effect of VL on increased cardiovascular risk (β=.134, SE 0.014; P=.006). We obtained similar results with Cardiac Risk Score1, but the effect of CD4 lymphocyte counts of ≤200 was no longer significant. Overall, our findings suggest that detectable VL is associated with increased cardiovascular risk among youths living with HIV, and that CD4 lymphocyte counts may play a role in this relationship as well.

CONCLUSIONS

Our study highlights a significant association between unsuppressed HIV, indicated by detectable VL, and increased cardiovascular risk in youths living with HIV. These findings emphasize the importance of implementing interventions that address both VL suppression and cardiovascular risk reduction in this population. By tailoring interventions to meet the unique needs of youths, we can promote overall well-being throughout the HIV care continuum and across the life span. Ultimately, these efforts have the potential to improve the health outcomes and quality of life of youths living with HIV.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.2196/11185.

Cardiovascular disease and risk assessment in people living with HIV: Current practices and novel perspectives

Human immunodeficiency virus (HIV) infection represents a major cardiovascular risk factor, and the cumulative cardiovascular disease (CVD) burden among aging people living with HIV (PLWH) constitutes a leading cause of morbidity and mortality. To date, CVD risk assessment in PLWH remains challenging. Therefore, it is necessary to evaluate and stratify the cardiovascular risk in PLWH with appropriate screening and risk assessment tools and protocols to correctly identify which patients are at a higher risk for CVD and will benefit most from prevention measures and timely management. This review aims to accumulate the current evidence on the association between HIV infection and CVD, as well as the risk factors contributing to CVD in PLWH. Furthermore, considering the need for cardiovascular risk assessment in daily clinical practice, the purpose of this review is also to report the current practices and novel perspectives in cardiovascular risk assessment of PLWH and provide further insights into the development and implementation of appropriate CVD risk stratification and treatment strategies, particularly in countries with high HIV burden and limited resources.

Carnitine Is Associated With Atherosclerotic Risk and Myocardial Infarction in HIV -Infected Adults

Background

People living with HIV (PLWH) have an increased risk of myocardial infarction (MI). Changes in the gut microbiota that occur with chronic HIV infection could play a role in HIV‐associated atherosclerosis. Choline, carnitine, betaine, and trimethylamine N‐oxide are small molecules that are, in part, metabolized or produced by the gut microbiome. We hypothesized that these metabolites would be associated with carotid artery intima‐media thickness and MI in PLWH.

Methods and Results

Carotid artery intima‐media thickness was measured at baseline and at a median interval of 4 years in 162 PLWH from the SCOPE (Study of the Consequences of the Protease Inhibitor Era) cohort in San Francisco, CA. Separately, 105 PLWH (36 cases with type I adjudicated MI and 69 controls without MI) were selected from the Center for AIDS Research Network of Integrated Clinical Systems, a multicenter clinic‐based cohort. Controls were matched by demographics, CD4 cell count, and duration of viral suppression. In the SCOPE cohort, higher carnitine levels had a significant association with presence of carotid plaque and greater baseline and progression of mean carotid artery intima‐media thickness after adjusting for traditional cardiovascular disease risk factors. In the treated and suppressed subgroup, these associations with carnitine remained significant after adjustment for cardiovascular disease risk factors. In the Center for AIDS Research Network of Integrated Clinical Systems cohort, the risk of MI was significantly increased in subjects with carnitine levels in the highest quartile after adjustment for cardiovascular disease risk factors.

Conclusions

In PLWH, including the treated and suppressed subgroup, carnitine is independently associated with carotid artery intima‐media thickness, carotid plaque, and MI in 2 separate cohorts. These results emphasize the potential role of gut microbiota in HIV‐associated atherosclerosis and MI, especially in relation to carnitine metabolism.

HIV-related cardiovascular diseases: the search for a unifying hypothesis

Although the extensive rollout of antiretroviral (ARV) therapy resulted in a longer life expectancy for people living with human immunodeficiency virus (PLHIV), such individuals display a relatively increased occurrence of cardiovascular diseases (CVD). This health challenge stimulated significant research interests in the field, leading to an improved understanding of both lifestyle-related risk factors and the underlying mechanisms of CVD onset in PLHIV. However, despite such progress, the precise role of various risk factors and mechanisms underlying the development of HIV-mediated CVD still remains relatively poorly understood. Therefore, we review CVD onset in PLHIV and focus on 1) the spectrum of cardiovascular complications that typically manifest in such persons and 2) underlying mechanisms that are implicated in this process. Here, the contributions of such factors and modulators and underlying mechanisms are considered in a holistic and integrative manner to generate a unifying hypothesis that includes identification of the core pathways mediating CVD onset. The review focuses on the sub-Saharan African context, as there are relatively high numbers of PLHIV residing within this region, indicating that the greater CVD risk will increasingly threaten the well-being and health of its citizens. It is our opinion that such an approach helps point the way for future research efforts to improve treatment strategies and/or lifestyle-related modifications for PLHIV.

HIV infection and coronary heart disease: mechanisms and management

Antiretroviral therapy has largely transformed HIV infection into a chronic disease condition. As such, physicians and other providers caring for individuals living with HIV infection need to be aware of the potential cardiovascular complications of HIV infection and the nuances of how HIV infection increases the risk of cardiovascular diseases, including acute myocardial infarction, stroke, peripheral artery disease, heart failure and sudden cardiac death, as well as how to select available therapies to reduce this risk. In this Review, we discuss the epidemiology and clinical features of cardiovascular disease, with a focus on coronary heart disease, in the setting of HIV infection, which includes a substantially increased risk of myocardial infarction even when the HIV infection is well controlled. We also discuss the mechanisms underlying HIV-associated atherosclerotic cardiovascular disease, such as the high rates of traditional cardiovascular risk factors in patients with HIV infection and HIV-related factors, including the use of antiretroviral therapy and chronic inflammation in the setting of effectively treated HIV infection. Finally, we highlight available therapeutic strategies, as well as approaches under investigation, to reduce the risk of cardiovascular disease and lower inflammation in patients with HIV infection.

Immune Disorder in Atherosclerotic Cardiovascular Disease - Clinical Implications of Using Circulating T-Cell Subsets as Biomarkers

Atherosclerotic cardiovascular disease (ACVD) is an inflammatory phenomenon that leads to structural abnormality in the vascular lumen due to the formation of atheroma by the deposition of lipid particles and inflammatory cytokines. There is a close interaction between innate immune cells (neutrophils, monocyte, macrophages, dendritic cells) and adaptive immune cells (T and B lymphocytes) in the initiation and progression of atherosclerosis. According to novel insights into the role of adaptive immunity in atherosclerosis, the activation of CD4⁺T cells in response to oxidized low-density lipoprotein-antigen initiates the formation and facilitates the propagation of atheroma, whereas CD8⁺T cells cause the rupture of a developed atheroma by their cytotoxic nature. Peripheral CD4⁺and CD8⁺T-cell counts were altered in patients with other cardiovascular risk factors. Furthermore, on evaluation of the feasibility of immune cells as a diagnostic tool, the blood CD4⁺(helper), CD8⁺(cytotoxic), and CD4⁺CD25⁺Foxp3⁺(regulatory) T cells and the ratio of CD4 to CD8 cells hold promise as biomarkers of coronary artery disease and their subtypes. T cells also could be a therapeutic target for cardiovascular diseases. The goal of this review was therefore to summarize the available information regarding immune disorders in ACVD with a special focus on the clinical implications of circulating T-cell subsets as biomarkers.

Promoting Cardiovascular Health in Patients Living with Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome

Patients living with human immunodeficiency virus/acquired immunodeficiency syndrome (PLWHA) are at increased risk of cardiovascular disease because of advances in human immunodeficiency virus/acquired immunodeficiency syndrome treatment and increased life expectancy. Cardiovascular health promotion in PLWHA includes strategies for risk factor reduction, disease prevention, early detection, and treatment of cardiovascular disease.

Non-diagnostic anti-C. burnetii phase I IgG titres: Should they be discarded in elderly patients?

BACKGROUND

High anti-Coxiella burnetii phase I IgG titres are associated with chronic Q fever; an infectious disease with high mortality. Prognostic significance of lower or medium IgG phase I titres remain uncertain. The aim of this study was to explore this issue in a high-risk population.

METHODS

Sero-epidemiological and prospective study of 456 hospitalised patients aged 65 and older (Burgos; Spain). Serum IgG antibody phase I and II were determined by immunofluorescence assay.

RESULTS

A lower or medium IgG phase I titres (<1:1024) was observed in 180 (39.4%) patients. Atherosclerotic cardiovascular disease was associated with these titres, but not the traditional risk factors of chronic Q fever (cardiac valve disease, and vascular grafts or valvular prosthesis) (adjusted OR 1.75, 95% CI 1.18-2.61). Lower or medium IgG phase I titres were also associated with decreased survival at 30 months follow-up in patients with atherosclerotic cardiovascular disease (but not in the total sample) after adjusting for others comorbidities: IgG phase I titres≥1:32 (HR 1.77; 95% CI 1.14 4-2.74), ≥1:64 (HR 1.90; 95% CI 1.21-2.99)-3.25), and ≥1:128 (HR 2.00; 95% CI 1.23-3.25).

CONCLUSION

Lower or medium IgG phase I titres against C. burnetii, even the lowest, should not be discarded in elderly patients with atherosclerotic cardiovascular disease. Serological follow-up should be recommended in this group of patients.

Posttransplant Immune Activation: Innocent Bystander or Insidious Culprit of Posttransplant Accelerated Atherosclerosis

Cardiovascular disease is a major cause of morbidity, disability, and mortality in kidney transplant patients. Cumulative reports indicate that the excessive risk of cardiovascular events is not entirely explained by the increased prevalence of traditional cardiovascular risk factors. Atherosclerosis is a chronic inflammatory disease, and it has been postulated that posttransplant immune disturbances may explain the gap between the predicted and observed risks of cardiovascular events. Although concordant data suggest that innate immunity contributes to the posttransplant accelerated atherosclerosis, only few arguments plead for a role of adaptive immunity. We report and discuss here consistent data demonstrating that CD8⁺ T cell activation is a frequent posttransplant immune feature that may have pro-atherogenic effects. Expansion of exhausted/activated CD8⁺ T cells in kidney transplant recipients is stimulated by several factors including cytomegalovirus infections, lymphodepletive therapy (e.g., antithymocyte globulins), chronic allogeneic stimulation, and a past history of renal insufficiency. This is observed in the setting of decreased thymic activity, a process also found in elderly individuals and reflecting accelerated immune senescence.

Cardiovascular Disease in the Setting of Human Immunodeficiency Virus Infection

Background:

Since the introduction of Antiretroviral Therapy (ART), the life expectancy and health quality for patients infected with Human Immunodeficiency Virus (HIV) have significant-ly improved. Nevertheless, as a result of not only the deleterious effects of the virus itself and pro-longed ART, but also the effects of aging, cardiovascular diseases have emerged as one of the most common causes of death among these patients.

Objective:

The purpose of this review is to explore the new insights on the spectrum of Cardiovascu-lar Disease (CVD) in HIV infection, with emphasis on the factors that contribute to the atherosclerot-ic process and its role in the development of acute coronary syndrome in the setting of infection.

Methods:

A literature search using PubMed, ScienceDirect and Web of Science was performed. Ar-ticles up to Mar, 2017, were selected for inclusion. The search was conducted using MeSH terms, with the following key terms: [human immunodeficiency virus AND (cardiovascular disease OR coronary heart disease) AND (antiretroviral therapy AND (cardiovascular disease OR coronary heart disease))].

Results:

Clinical cardiovascular disease tends to appear approximately 10 years before in infected in-dividuals, when compared to the general population. The pathogenesis behind the cardiovascular, HIV-associated complications is complex and multifactorial, involving traditional CVD risk factors, as well as factors associated with the virus itself - immune activation and chronic inflammation – and the metabolic disorders related to ART regimens.

Conclusion:

Determining the cardiovascular risk among HIV-infected patients, as well as targeting and treating conditions that predispose to CVD, are now emerging concerns among physicians.

Aortic stiffness aging is influenced by past profound immunodeficiency in HIV-infected individuals: results from the EVAS-HIV (EValuation of Aortic Stiffness in HIV-infected individuals)

OBJECTIVE

We compared aortic stiffness between HIV-infected and HIV-uninfected individuals and examined the determinants of vascular aging during HIV infection.

METHODS

Aortic stiffness using carotid-femoral pulse wave velocity (cf-PWV) was evaluated cross-sectionally between HIV-infected individuals and uninfected controls frequency-matched for age and sex, and longitudinally in a subgroup of HIV-infected individuals. Determinants of elevated cf-PWV levels were assessed using logistic regression. Changes in cf-PWV levels during follow-up (mixed-effect linear regression) and risk factors for achieving cf-PWV below (Group 1) or above the median (Group 2) at last follow-up visit were evaluated only in HIV-infected individuals.

RESULTS

A total of 133 HIV-infected and 135 HIV-uninfected individuals (mean age: 47.7 ± 8.9 years, 91% men) were enrolled. Median cf-PWV at baseline was similar between HIV-infected individuals and controls [7.5 m/s (interquartile range = 6.7-8.4) vs. 7.5 m/s (interquartile range = 6.6-8.4), respectively; P = 0.64]. In multivariable analysis, only mean arterial pressure showed significant association with elevated cf-PWV in the overall population (P = 0.036). In HIV-infected individuals, elevated cf-PWV was associated with current smoking (P = 0.042), and nadir CD4 T-cell count less than 200 cells/μl (P = 0.048). Ninety-one HIV-infected individuals were followed for a mean 7.6 ± 2.0 years. cf-PWV progression was associated with age (P = 0.018), mean arterial pressure (P = 0.020), and nadir CD4 T-cell count (P = 0.005). Patients from Group 2 had higher baseline waist circumference, pulse pressure, and nadir CD4 T-cell count less than 200 cells/μl.

CONCLUSION

We observed no difference in aortic stiffness between HIV-infected and controls. Moreover, aortic stiffness aging was independently associated with past severe immunodeficiency, along with other traditional risk factors. Our results call for early antiretroviral initiation.

Role of T-Cell Dysfunction, Inflammation, and Coagulation in Microvascular Disease in HIV

BACKGROUND

Compared to uninfected adults, HIV-infected adults on antiretroviral therapy are at increased risk of cardiovascular disease. Given the increase in T-cell dysfunction, inflammation, and coagulation in HIV infection, microvascular dysfunction is thought to contribute to this excess cardiovascular risk. However, the relationships between these variables remain undefined.

METHODS AND RESULTS

This was a cross-sectional study of 358 HIV-infected adults from the SCOPE cohort. Macrovascular endothelial function was assessed using flow-mediated dilation of the brachial artery and microvascular function by reactive hyperemia. T-cell phenotype was determined by flow cytometry. Plasma markers of inflammation (tumor necrosis factor-α, interleukin-6, high-sensitivity C-reactive protein, sCD14) and coagulation (fibrinogen, D-dimer) were also measured. In all HIV+ subjects, markers of inflammation (tumor necrosis factor-α, high-sensitivity C-reactive protein), coagulation (D-dimer) and T-cell activation (CD8+PD1+, CD4+interferon+cytomegalovirus-specific) were associated with worse reactive hyperemia after adjusting for traditional cardiovascular risk factors and co-infections. In treated and suppressed subjects, tumor necrosis factor-α and CD8+PD1+ cells remained associated with worse reactive hyperemia after adjustment. Compared to the untreated subjects, CD8+PD1+ cells were increased in the virally suppressed group. Reactive hyperemia was predictive of flow-mediated dilation.

CONCLUSIONS

CD8+PD1+ cells and tumor necrosis factor-α were associated with microvascular dysfunction in all HIV+ subjects and the treated and suppressed group. Additionally, D-dimer, high-sensitivity C-reactive protein, sCD-14, and interleukin-6 were associated with microvascular dysfunction in all HIV+ subjects. Although T-cell dysfunction, inflammation, and microvascular dysfunction are thought to play a role in cardiovascular disease in HIV, this study is the first to look at which T-cell and inflammatory markers are associated with microvascular dysfunction in HIV-infected individuals.

Greater carotid intima media thickness at a younger age in HIV-infected patients compared with reference values for an uninfected cohort

OBJECTIVES

In contrast to the general population, no decline in cardiovascular disease (CVD) has been noted in HIV-infected patients over the last 10 years. We compared the carotid artery intima media thickness (CIMT) of HIV-infected patients to that of age- and gender-matched reference values and determined the relationship between CVD risk factors and CIMT.

METHODS

A total of 292 HIV-infected patients were enrolled in the study. Data collected included vascular screening data, data obtained using a questionnaire, data obtained from laboratory assessments and CIMT measurement. Using linear regression (adjusted for age/gender/known HIV), the association between HIV-specific and classical cardiovascular risk factors and CIMT was evaluated.

RESULTS

The cohort comprised for 91% of male patients, aged 49.4 ± 10.5 years, with a known duration of HIV infection of 8.8 ± 6.7 years. The mean with standard deviation (mean ± SD) CIMT was 0.77 ± 0.19 mm, compared with 0.58 ± 0.05 mm in the controls. A steeper increase of CIMT per age was seen in the HIV-infected patients. A significant relationship between CIMT and hypertension, diabetes mellitus, smoking, systolic blood pressure, HbA1c (glycated hemoglobin) and ankle brachial index was found. Of the HIV-specific variables, only a relationship between CIMT and length of cART use and between CIMT and (inversely) current cART use was seen.

CONCLUSIONS

A greater CIMT was found in HIV-infected patients compared with controls. In contrast to HIV-specific variables, classical CVD risk factors were associated with a greater CIMT and should therefore be the focus of preventive measures.

Maraviroc Intensification Improves Endothelial Function in Abacavir-Treated Patients, an Open-Label Randomized Cross-Over Pilot Study

Background

The increased risk of abacavir in cardiovascular disease (CVD) in HIV-infected patients is still being debated. Maraviroc, a CCR5 blocker, has been shown to decrease immune activation and monocyte infiltration in atherosclerotic plaques in murine experiments. Therefore, we examined the effect of maraviroc intensification on flow-mediated dilatation (FMD) in abacavir-treated HIV-infected patients and its effect on immunological and inflammatory parameters.

Methods

A open-label prospective crossover study with a duration of 16 weeks: 8 weeks of intervention (maraviroc intensification) and 8 weeks of control (unchanged cART regimen). FMD, HIV-specific variables, expression of HIV co-receptors, markers of inflammation and coagulation and cellular markers of immune activation were measured at weeks 0, 8 and 16. The changes (Δ) in these variables were compared between intervention and control periods using non-parametric tests. To evaluate the relation with the change in FMD, linear regression modeling was used.

Results

Twenty-one male patients with suppressed plasma HIV-RNA, on cART, had a known HIV infection for 9.2 years (IQR 6.9–13.5) with abacavir use for 6.5 years (2.8–9.3). A significantly increased FMD of 0.73% (IQR −0.25 to 1.70) was seen after maraviroc intensification compared to a decrease of −0.42% (IQR −1.89 to 0.25; p = 0.049) in the control period. There was a negative relation between ΔFMD with ΔD-dimer (β −22.70, 95% CI −39.27; −6.13, p = 0.011) and ΔCD95+ CD4+ T cells (β −0.16, 95% CI −0.28; −0.04, p = 0.013), adjusted for age and duration of HIV.

Conclusion

Maraviroc intensification modestly improves endothelial function in HIV-infected patients on an abacavir-containing regimen.

Trial registration

NCT01389063.

Electronic supplementary material

The online version of this article (doi:10.1007/s40121-016-0115-0) contains supplementary material, which is available to authorized users.

Antiretroviral treatment use, co-morbidities and clinical outcomes among Aboriginal participants in the Australian HIV Observational Database (AHOD)

Background

There are few data regarding clinical care and outcomes of Indigenous Australians living with HIV and it is unknown if these differ from non-Indigenous HIV-positive Australians.

Methods

AHOD commenced enrolment in 1999 and is a prospective cohort of HIV-positive participants attending HIV outpatient services throughout Australia, of which 20 (74 %) sites report Indigenous status. Data were collected up until March 2013 and compared between Indigenous and non-Indigenous participants. Person-year methods were used to compare death rates, rates of loss to follow-up and rates of laboratory testing during follow-up between Indigenous and non-Indigenous participants. Factors associated with time to first combination antiretroviral therapy (cART) regimen change were assessed using Kaplan Meier and Cox Proportional hazards methods.

Results

Forty-two of 2197 (1.9 %) participants were Indigenous. Follow-up amongst Indigenous and non-Indigenous participants was 332 & 16270 person-years, respectively. HIV virological suppression was achieved in similar proportions of Indigenous and non-Indigenous participants 2 years after initiation of cART (81.0 % vs 76.5 %, p = 0.635). Indigenous status was not independently associated with shorter time to change from first- to second-line cART (aHR 0.95, 95 % CI 0.51-1.76, p = 0.957). Compared with non-Indigenous participants, Indigenous participants had significantly less frequent laboratory monitoring of CD4 count (rate:2.76 tests/year vs 2.97 tests/year, p = 0.025) and HIV viral load (rate:2.53 tests/year vs 2.93 tests/year, p < 0.001), while testing rates for lipids and blood glucose were almost half that of non-indigenous participants (rate:0.43/year vs 0.71 tests/year, p < 0.001). Loss to follow-up (23.8 % vs 29.8 %, p = 0.496) and death (2.4 % vs 7.1 %, p = 0.361) occurred in similar proportions of indigenous and non-Indigenous participants, respectively, although causes of death in both groups were mostly non-HIV-related.

Conclusions

As far as we are aware, these are the first data comparing clinical outcomes between Indigenous and non-Indigenous HIV-positive Australians. The forty-two Indigenous participants represent over 10 % of all Indigenous Australians ever diagnosed with HIV. Although outcomes were not significantly different, Indigenous patients had lower rates of laboratory testing for HIV and lipid/glucose parameters. Given the elevated risk of cardiovascular disease in the general Indigenous community, the additional risk factor of HIV infection warrants further focus on modifiable risk factors to maximise life expectancy in this population.

Stimulating high impact HIV-related cardiovascular research: recommendations from a multidisciplinary NHLBI Working Group on HIV-related heart, lung, and blood disease

The clinical challenges confronting patients with human immunodeficiency virus (HIV) have shifted from acquired immunodeficiency syndrome (AIDS)-related illnesses to chronic diseases, such as coronary artery disease, chronic lung disease, and chronic anemia. With the growing burden of HIV-related heart, lung, and blood (HLB) disease, the National Heart, Lung, and Blood Institute (NHLBI) recognizes it must stimulate and support HIV-related HLB research. Because HIV offers a natural, accelerated model of common pathological processes, such as inflammation, HIV-related HLB research may yield important breakthroughs for all patients with HLB disease. This paper summarizes the cardiovascular recommendations of an NHLBI Working Group, Advancing HIV/AIDS Research in Heart, Lung, and Blood Diseases, charged with identifying scientific priorities in HIV-related HLB disease and developing recommendations to promote multidisciplinary collaboration among HIV and HLB investigators. The working group included multidisciplinary sessions, as well as HLB breakout sessions for discussion of disease-specific issues, with common themes about scientific priorities and strategies to stimulate HLB research emerging in all 3 groups.

The role of T and B cells in human atherosclerosis and atherothrombosis

Far from being merely a passive cholesterol accumulation within the arterial wall, the development of atherosclerosis is currently known to imply both inflammation and immune effector mechanisms. Adaptive immunity has been implicated in the process of disease initiation and progression interwined with traditional cardiovascular risk factors. Although the body of knowledge regarding the correlation between atherosclerosis and immunity in humans is growing rapidly, a relevant proportion of it derives from studies carried out in animal models of cardiovascular disease (CVD). However, while the mouse is a well-suited model, the results obtained therein are not fully transferrable to the human setting due to intrinsic genomic and environmental differences. In the present review, we will discuss mainly human findings, obtained either by examination of post-mortem and surgical atherosclerotic material or through the analysis of the immunological profile of peripheral blood cells. In particular, we will discuss the findings supporting a pro-atherogenic role of T cell subsets, such as effector memory T cells or the potential protective function of regulatory T cells. Recent studies suggest that traditional T cell-driven B2 cell responses appear to be atherogenic, while innate B1 cells appear to exert a protective action through the secretion of naturally occurring antibodies. The insights into the immune pathogenesis of atherosclerosis can provide new targets in the quest for novel therapeutic targets to abate CVD morbidity and mortality.