Inflammatory cytokines and inhibitors in HIV infection: correlation between interleukin-1 receptor antagonist and weight loss

Pidotimod and Immunological Activation in Individuals Infected with HIV

BACKGROUND

The improvements in HIV infection therapy and the large availability of antiretroviral drugs have led to an increased survival among HIV infected people, and simultaneously to a raised morbidity and mortality due to not-AIDS-related events in this group compared to the general population. An increased systemic inflammation and a persistent immune activation play a pivotal role in determining high rates of non-AIDS comorbidities. In the last years, many natural or synthetic immunomodulatory molecules acting by different mechanisms have been conceived. Pidotimod is a synthetic dipeptide molecule showing immunomodulatory properties. The aim of this pilot study was to evaluate the effects of Pidotimod supplementation on residual inflammation in HIV infected population.

METHODS

Forty HIV positive individuals under cART were enrolled: 30 were treated with Pidotimod supplementation (study group) and 10 served as control group (without Pidotimod supplementation). For all participants, Cystatin C, PCR, ESR, microalbuminuria, TNF-α, INF-γ, IL-4, IL-10, IL1β, IL-18 and IL-2 were measured at enrolment (T0), 4 weeks after of Pidotimod supplementation (T1), and 4 weeks after completing supplementation (T2).

RESULTS

In HIV positive participants treated with Pidotimod, the evaluation of cytokine levels showed that IL-10, IFN gamma, and IL-4 were significantly higher at enrolment compared to the control group. The increase under Pidotimod treatment persisted after supplementation suspension, while the pro-inflammatory cytokines levels were reduced. Salivary IgA also increased during 4 weeks of supplementation and persisted at 4 weeks after completing supplementation. On the other hand, the Cystatin C and microalbuminuria levels decreased over time, at a greater extent the Cystatin C serum levels.

CONCLUSION

The study findings showed that the HIV population receiving Pidotimod achieved a rebalancing of pro-inflammatory and anti-inflammatory cytokines as well as a significant reduction in cystatin C levels. The treatment further allowed for an increase in salivary IgA levels at all the analyzed times, as a secondary event to a remodulation of the immunological status obtained with pidotimod. This approach could represent a new way to design new intervention strategies aimed at improving the persistent immune activation status in the virologically suppressed HIV population.

Impact of Immune Reconstitution-Induced Hepatic Flare on Hepatitis B Surface Antigen Loss in Hepatitis B Virus/Human Immunodeficiency Virus-1 Coinfected Patients

BACKGROUND

Hepatitis B surface antigen (HBsAg) loss is an ideal goal for chronic hepatitis B patients. Antiretroviral therapy (ART) in hepatitis B virus/human immunodeficiency virus-1 (HBV/HIV-1)-coinfected patients can lead to hepatic flare (HF) caused by immune reconstitution-induced inflammatory syndrome (IRIS). Here, we investigated the impact of IRIS-HF on HBsAg loss.

METHODS

This was a retrospective study of 58 HBV/HIV-1-coinfected subjects HBsAg-positive for ≥6 months before ART initiation and followed for ≥1 year (median 9.9 years) after ART initiation. We examined humoral factors in sera from healthy volunteers, HIV-monoinfected patients, and HBV/HIV-1-coinfected patients with IRIS-HF or acute hepatitis B infection.

RESULTS

During ART, HBsAg loss was observed in 20 of 58 HBV/HIV-1-coinfected patients (34.5%). Of the 58 patients, 15 (25.9%) developed IRIS-HF within 12 months of ART initiation. HBsAg loss was more frequent among patients who developed IRIS-HF (11/15, 73.3%) than those who did not (9/43, 20.9%). Multivariate analysis showed IRIS-HF was an independent predictor of subsequent HBsAg loss. Younger age and higher baseline HBV DNA titer were associated with IRIS-HF. Elevation of sCD163, not CXCL9, CXC10, CXCXL11, or CXCL13, was observed at IRIS-HF.

CONCLUSIONS

IRIS-HF was associated with HBsAg loss in HBV/HIV-1-coinfected patients.

Impact of Alcohol on HIV Disease Pathogenesis, Comorbidities and Aging: Integrating Preclinical and Clinical Findings

Short Summary

: Effective combined antiretroviral therapy regimens have extended survival of persons living with HIV (PLWH). Heavy alcohol consumption is common in PLWH. This overview integrates evidence from clinical and preclinical research to identify salient alcohol-related mechanisms and comorbidities contributing to disease pathogenesis and accelerated aging and senescence in PLWH.

Interleukin-1 blockade overcomes erlotinib resistance in head and neck squamous cell carcinoma

Erlotinib has demonstrated poor clinical response rates for head and neck squamous cell carcinoma (HNSCC) to date and the majority of respondents acquire resistance to erlotinib relatively quickly. To elucidate novel pathways involved in erlotinib resistance, we compared the gene expression profiles of erlotinib-resistant (ER) vs. erlotinib-sensitive (ES) HNSCC cell lines. Enrichment analysis of microarray data revealed a deregulation of the IL-1 signaling pathway in ER versus ES-HNSCC cells. Gene expression of interleukin-1 alpha (IL1A) and interleukin-1 beta (IL1B) were significantly upregulated by > 2 fold in ER-SQ20B and ER-CAL 27 cells compared to their respective ES-cells. Secretion of the IL-1 receptor antagonist (IL-1RA) was significantly reduced in ER-cells compared to ES-cells. Blockade of IL-1 signaling using a recombinant IL-1R antagonist (anakinra) was able to inhibit the growth of ER-SQ20B and ER-CAL 27 but not ES-SQ20B and ES-CAL 27 xenografts as a single agent and in combination with erlotinib. ER-SQ20B xenografts treated with anakinra ± erlotinib were found to be less vascularized than ER-SQ20B xenografts treated with water or erlotinib. Mice bearing ER-SQ20B xenografts had significantly lesser circulating levels of G-CSF and IL-1β when treated with anakinra ± erlotinib compared to those treated with water or erlotinib alone. Furthermore, augmented mRNA levels of IL1A or interleukin-1 receptor accessory protein (IL1RAP) were associated with shortened survival in HNSCC patients. Altogether, blockade of the IL-1 pathway using anakinra overcame erlotinib resistance in HNSCC xenografts and may represent a novel strategy to overcome EGFR inhibitor resistance for treatment of HNSCC patients.

Role of high-sensitivity C-reactive protein measurements in HIV patients

As we herald into the 21st century, the quality of life and the repertoire of highly active antiretroviral therapy (HAART) have considerably improved. However, considerable work is still needed to educate the population about primary and secondary prevention modalities. Moreover, regular monitoring of immune response with patients on HAART with conventional biomarkers is still a problem in low resource settings which needs to be addressed. We aim to review high-sensitivity C-reactive protein as a potential biomarker in this regard.

Persistently Elevated C-Reactive Protein Level in the First Year of Antiretroviral Therapy, Despite Virologic Suppression, Is Associated With HIV Disease Progression in Resource-Constrained Settings

A case-cohort analysis of human immunodeficiency virus (HIV)-infected individuals receiving antiretroviral therapy (ART) was performed within a multicountry randomized trial (PEARLS) to assess the prevalence of persistently elevated C-reactive protein (CRP) levels, based on serial measurements of CRP levels, and their association with HIV clinical failure. A persistently elevated CRP level in plasma (defined as ≥ 5 mg/L at both baseline and 24 weeks after ART initiation) was observed in 50 of 205 individuals (24%). A persistently elevated CRP level but not an elevated CRP level only at a single time point was independently associated with increased clinical failure, compared with a persistently low CRP level, despite achievement of virologic suppression. Serial monitoring of CRP levels could identify individuals who are at highest risk of HIV progression and may benefit from future adjunct antiinflammatory therapies.

Concurrent Anemia and Elevated C-Reactive Protein Predicts HIV Clinical Treatment Failure, Including Tuberculosis, After Antiretroviral Therapy Initiation

BACKGROUND

Anemia is a known risk factor for clinical failure following antiretroviral therapy (ART). Notably, anemia and inflammation are interrelated, and recent studies have associated elevated C-reactive protein (CRP), an inflammation marker, with adverse human immunodeficiency virus (HIV) treatment outcomes, yet their joint effect is not known. The objective of this study was to assess prevalence and risk factors of anemia in HIV infection and to determine whether anemia and elevated CRP jointly predict clinical failure post-ART.

METHODS

A case-cohort study (N = 470 [236 cases, 234 controls]) was nested within a multinational randomized trial of ART efficacy (Prospective Evaluation of Antiretrovirals in Resource Limited Settings [PEARLS]). Cases were incident World Health Organization stage 3, 4, or death by 96 weeks of ART treatment (clinical failure). Multivariable logistic regression was used to determine risk factors for pre-ART (baseline) anemia (females: hemoglobin <12.0 g/dL; males: hemoglobin <13.0 g/dL). Association of anemia as well as concurrent baseline anemia and inflammation (CRP ≥ 10 mg/L) with clinical failure were assessed using multivariable Cox models.

RESULTS

Baseline anemia prevalence was 51% with 15% prevalence of concurrent anemia and inflammation. In analysis of clinical failure, multivariate-adjusted hazard ratios were 6.41 (95% confidence interval [CI], 2.82-14.57) for concurrent anemia and inflammation, 0.77 (95% CI, .37-1.58) for anemia without inflammation, and 0.45 (95% CI, .11-1.80) for inflammation without anemia compared to those without anemia and inflammation.

CONCLUSIONS

ART-naive, HIV-infected individuals with concurrent anemia and inflammation are at particularly high risk of failing treatment, and understanding the pathogenesis could lead to new interventions. Reducing inflammation and anemia will likely improve HIV disease outcomes. Alternatively, concurrent anemia and inflammation could represent individuals with occult opportunistic infections in need of additional screening.

Biomedical consequences of alcohol use disorders in the HIV-infected host

Alcohol abuse is the most common and costly form of drug abuse in the United States. It is well known that alcohol abuse contributes to risky behaviors associated with greater incidence of human immunodeficiency virus (HIV) infections. As HIV has become a more chronic disease since the introduction of antiretroviral therapy, it is expected that alcohol use disorders will have an adverse effect on the health of HIV-infected patients. The biomedical consequences of acute and chronic alcohol abuse are multisystemic. Based on what is currently known of the comorbid and pathophysiological conditions resulting from HIV infection in people with alcohol use disorders, chronic alcohol abuse appears to alter the virus infectivity, the immune response of the host, and the progression of disease and tissue injury, with specific impact on disease progression. The combined insult of alcohol abuse and HIV affects organ systems, including the central nervous system, the immune system, the liver, heart, and lungs, and the musculoskeletal system. Here we outline the major pathological consequences of alcohol abuse in the HIV-infected individual, emphasizing its impact on immunomodulation, erosion of lean body mass associated with AIDS wasting, and lipodystrophy. We conclude that interventions focused on reducing or avoiding alcohol abuse are likely to be important in decreasing morbidity and improving outcomes in people living with HIV/AIDS.

MyD88-dependent signaling prolongs survival and reduces bacterial burden during pulmonary infection with virulent Francisella tularensis

Francisella tularensis is the causative agent of the debilitating febrile illness tularemia. The severe morbidity associated with F. tularensis infections is attributed to its ability to evade the host immune response. Innate immune activation is undetectable until more than 48 hours after infection. The ensuing inflammatory response is considered pathological, eliciting a septic-like state characterized by hypercytokinemia and cell death. To investigate potential pathological consequences of the innate immune response, mice deficient in a key innate immune signaling molecule, MyD88, were studied. MyD88 knockout (KO) mice were infected with the prototypical virulent F. tularensis strain, Schu S4. MyD88 KO mice succumbed to infection more rapidly than wild-type mice. The enhanced pathogenicity of Schu S4 in MyD88 KO mice was associated with greater bacterial burdens in lungs and distal organs, and the absence of IFN-γ in the lungs, spleens, and sera. Cellular infiltrates were not observed on histological evaluation of the lungs, livers, or spleens of MyD88 KO mice, the first KO mouse described with this phenotype to our knowledge. Despite the absence of cellular infiltration, there was more cell death in the lungs of MyD88 KO mice. Thus, the host proinflammatory response is beneficial, and MyD88 signaling is required to limit bacterial burden and prolong survival during pulmonary infection by virulent F. tularensis.

Vitamin D status and incidence of pulmonary tuberculosis, opportunistic infections, and wasting among HIV-infected Tanzanian adults initiating antiretroviral therapy

BACKGROUND

Maintaining vitamin D sufficiency may decrease the incidence of pulmonary tuberculosis and other infectious diseases. We present the first prospective study of vitamin D among human immunodeficiency virus (HIV)-infected adults receiving antiretrovirals in sub-Saharan Africa.

METHODS

Serum 25-hydroxyvitamin D (25(OH)D) level was assessed at antiretroviral therapy (ART) initiation for 1103 HIV-infected adults enrolled in a trial of multivitamins (not including vitamin D) in Tanzania. Participants were prospectively followed at monthly visits at which trained physicians performed a clinical examination and nurses took anthropometric measurements and assessed self-reported symptoms. Cox proportional hazards models estimated hazard ratios (HRs) of morbidity outcomes.

RESULTS

After multivariate adjustment, vitamin D deficiency (defined as a concentration of <20 ng/mL) had a significantly greater association with incident pulmonary tuberculosis, compared with vitamin D sufficiency (HR, 2.89; 95% confidence interval [CI], 1.31-7.41; P = .027), but no association was found for vitamin D insufficiency (defined as a concentration of 20-30 ng/mL; P = .687). Deficiency was also significantly associated with incident oral thrush (HR, 1.96; 95% CI, 1.01-3.81; P = .046), wasting (HR, 3.10; 95% CI, 1.33-7.24; P = .009), and >10% weight loss (HR, 2.10; 95% CI, 1.13-3.91; P = .019). Wasting results were robust to exclusion of individuals experiencing pulmonary tuberculosis. Vitamin D status was not associated with incident malaria, pneumonia, or anemia.

CONCLUSIONS

Vitamin D supplementation trials for adults receiving ART appear to be warranted.

Vitamin D status and its association with morbidity including wasting and opportunistic illnesses in HIV-infected women in Tanzania

Vitamin D has a potential role in preventing HIV-related complications, based on its extensive involvement in immune and metabolic function, including preventing osteoporosis and premature cardiovascular disease. However, this association has not been examined in large studies or in resource-limited settings. Vitamin D levels were assessed in 884 HIV-infected pregnant women at enrollment in a trial of multivitamin supplementation (excluding vitamin D) in Tanzania. Information on HIV related complications was recorded during follow-up (median, 70 months). Proportional hazards models and generalized estimating equations were used to assess the relationship of vitamin D status with these outcomes. Women with low vitamin D status (serum 25-hydroxyvitamin D<32 ng/mL) had 43% higher risk of reaching a body mass index (BMI) less than 18 kg/m(2) during the first 2 years of follow-up, compared to women with adequate vitamin D levels (hazard ratio [HR]: 1.43; 95% confidence intervals: [1.03-1.99]). The relationship between continuous vitamin D levels and risk of BMI less than 18 kg/m(2) during follow-up was inverse and linear (p=0.03). Women with low vitamin D levels had significantly higher incidence of acute upper respiratory infections (HR: 1.27 [1.04-1.54]) and thrush (HR: 2.74 [1.29-5.83]) diagnosed during the first 2 years of follow-up. Low vitamin D status was a significant risk factor for wasting and HIV-related complications such as thrush during follow-up in this prospective cohort in Tanzania. If these protective associations are confirmed in randomized trials, vitamin D supplementation could represent a simple and inexpensive method to improve health and quality of life of HIV-infected patients, particularly in resource-limited settings.

Early myeloid dendritic cell dysregulation is predictive of disease progression in simian immunodeficiency virus infection

Myeloid dendritic cells (mDC) are lost from blood in individuals with human immunodeficiency virus (HIV) infection but the mechanism for this loss and its relationship to disease progression are not known. We studied the mDC response in blood and lymph nodes of simian immunodeficiency virus (SIV)-infected rhesus macaques with different disease outcomes. Early changes in blood mDC number were inversely correlated with virus load and reflective of eventual disease outcome, as animals with stable infection that remained disease-free for more than one year had average increases in blood mDC of 200% over preinfection levels at virus set-point, whereas animals that progressed rapidly to AIDS had significant loss of mDC at this time. Short term antiretroviral therapy (ART) transiently reversed mDC loss in progressor animals, whereas discontinuation of ART resulted in a 3.5-fold increase in mDC over preinfection levels only in stable animals, approaching 10-fold in some cases. Progressive SIV infection was associated with increased CCR7 expression on blood mDC and an 8-fold increase in expression of CCL19 mRNA in lymph nodes, consistent with increased mDC recruitment. Paradoxically, lymph node mDC did not accumulate in progressive infection but rather died from caspase-8-dependent apoptosis that was reduced by ART, indicating that increased recruitment is offset by increased death. Lymph node mDC from both stable and progressor animals remained responsive to exogenous stimulation with a TLR7/8 agonist. These data suggest that mDC are mobilized in SIV infection but that an increase in the CCR7-CCL19 chemokine axis associated with high virus burden in progressive infection promotes exodus of activated mDC from blood into lymph nodes where they die from apoptosis. We suggest that inflamed lymph nodes serve as a sink for mDC through recruitment, activation and death that contributes to AIDS pathogenesis.

Myeloid dendritic cells (mDC) are essential innate immune system cells that are lost from blood in human immunodeficiency virus infection through an ill-defined mechanism. We studied the kinetics of the mDC response in blood and lymph nodes of rhesus macaques infected with the closely related simian immunodeficiency virus. We found that differences in the number of blood mDC correlated with eventual disease outcome, as at virus set-point mDC were increased in blood in animals remaining disease free but lost from blood in animals that progressed rapidly to AIDS. mDC loss was linked to an increase in the chemokine axis responsible for mDC recruitment to lymph nodes; however, mDC did not accumulate in tissues but rather died from apoptosis. Lymph node mDC remained responsive to stimulation with a TLR7/8 agonist during infection. Importantly, mDC dysregulation was partially reversed by antiretroviral therapy. These data indicate that chronic mDC recruitment, activation and death within lymph nodes precede development of disease in SIV infected monkeys and may play a role in AIDS pathogenesis.

Short communication: Lack of immune response in rapid progressor morphine-dependent and SIV/SHIV-infected rhesus macaques is correlated with downregulation of TH1 cytokines

Our previous studies have shown two distinct disease patterns (rapid and normal onset of clinical symptoms) in morphine-dependent SHIV/SIV-inoculated rhesus macaques. We have also shown that control as well as 50% of morphine-dependent macaques (normal progressor) developed humoral and cellular immune responses whereas the other half of the morphine-dependent macaques (rapid progressor) did not develop antiviral immune responses after infection with SIV/SHIV. In the present study, we analyzed the association between cytokine production, immune response, and disease progression. To study the immunological effects of morphine at cytokine levels in the context of a lentiviral infection, we inoculated rhesus macaques with a mixture of SHIV(KU-18), SHIV(89.6)P, and SIV/17E-Fr. These animals were followed for a period of 56 weeks for cytokine level production in plasma. Drug-dependent rapid disease progressors exhibited an increase in IL-18 and IL-1Ra and a decrease in IL-12 levels in the plasma. Morphine-dependent normal progressors and control macaques exhibited an increase in both IL-18 and IL-12, whereas IL-Ra levels remained constant throughout the observation period. These results suggest that rapid disease progression in relation to morphine dependency may be the result of an altered cytokine profile.

Cross sectional analysis of respiratory symptoms in an injection drug user cohort: the impact of obstructive lung disease and HIV

Background

Injection drug use is associated with an increased risk of human immunodeficiency virus (HIV) infection and with obstructive lung diseases (OLD). Understanding how HIV and OLD may impact respiratory symptoms among injection drug users (IDUs) is important to adequately care for this high-risk population. We characterized the independent and joint effects of HIV and OLD on respiratory symptoms of a cohort of inner-city IDUs.

Methods

Demographics, risk behavior and spirometric measurements were collected from a cross-sectional analysis of the Acquired Immunodeficiency Syndrome Link to the IntraVenous Experience study, an observational cohort of IDUs followed in Baltimore, MD since 1988. Participants completed a modified American Thoracic Society respiratory questionnaire and the Medical Research Council (MRC) dyspnea score to assess respiratory symptoms of cough, phlegm, wheezing and dyspnea.

Results

Of 974 participants, 835 (86%) were current smokers and 288 (29.6%) were HIV-infected. The prevalence of OLD (FEV1/FVC ≤ 0.70) was 15.5%, and did not differ by HIV status. OLD, but not HIV, was associated with increased frequency of reported respiratory symptoms. There was a combined effect of OLD and HIV on worsening of MRC scores. OLD and HIV were independently associated with an increased odds of reporting an MRC ≥ 2 (OR 1.83 [95%CI 1.23-2.73] and 1.50 [95%CI 1.08-2.09], respectively). COPD, but not HIV, was independently associated with reporting an MRC ≥ 3 (OR 2.25 [95%CI 1.43-3.54] and 1.29 [95%CI 0.87-1.91], respectively).

Conclusions

While HIV does not worsen cough, phlegm or wheezing, HIV significantly increases moderate but not severe dyspnea in individuals of similar OLD status. Incorporating the MRC score into routine evaluation of IDUs at risk for OLD and HIV provides better assessment than cough, phlegm and wheezing alone.

Association of HIV infection and HIV/HCV coinfection with C-reactive protein levels: the fat redistribution and metabolic change in HIV infection (FRAM) study

OBJECTIVE

Inflammation is a potential mechanism to explain the accelerated atherosclerosis observed in HIV- and hepatitis C virus (HCV)-infected persons. We evaluated C-reactive protein (CRP) in HIV-infected and HIV/HCV-coinfected individuals in the era of effective antiretroviral (ARV) therapy.

DESIGN

Cross-sectional study of Fat Redistribution and Metabolic Change in HIV Infection (FRAM) cohort and controls from the Coronary Artery Risk Development in Young Adults (CARDIA) study.

METHODS

CRP levels were measured in 1135 HIV-infected participants from the FRAM cohort and 281 controls from the CARDIA study. The associations of HIV and HIV/HCV infection with CRP levels were estimated by multivariable linear regression.

RESULTS

Compared with controls, HIV monoinfection was associated with an 88% higher CRP level in men (P < 0.0001) but with no difference in women (5%; P = 0.80) in multivariate analysis. CRP levels were not associated with ARV therapy, HIV RNA level, or CD4 cell count. Compared with controls, HIV/HCV coinfection was associated with a 41% lower CRP level in women (P = 0.012) but with no difference in men (+4%; P = 0.90). Among HIV-infected participants, HCV coinfection was associated with 50% lower CRP levels after multivariable analysis (P < 0.0001) in men and women. Greater visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) were strongly associated with CRP levels. Among HIV-infected participants, CRP levels were 17% (P < 0.001) and 21% (P = 0.002) higher per doubling of VAT and SAT; among controls, CRP levels were 34% (P < 0.001) and 61% (P = 0.009) higher, respectively.

CONCLUSIONS

In the absence of HCV coinfection, HIV infection is associated with higher CRP levels in men. HCV coinfection is associated with lower CRP levels in men and women.

Nutritional indicators of adverse pregnancy outcomes and mother-to-child transmission of HIV among HIV-infected women

BACKGROUND

Poor nutrition may be associated with mother-to-child transmission (MTCT) of HIV and other adverse pregnancy outcomes.

OBJECTIVE

The objective was to examine the relation of nutritional indicators with adverse pregnancy outcomes among HIV-infected women in Tanzania, Zambia, and Malawi.

DESIGN

Body mass index (BMI; in kg/m(2)) and hemoglobin concentrations at enrollment and weight change during pregnancy were prospectively related to fetal loss, neonatal death, low birth weight, preterm birth, and MTCT of HIV.

RESULTS

In a multivariate analysis, having a BMI < 21.8 was significantly associated with preterm birth [odds ratio (OR): 1.82; 95% CI: 1.34, 2.46] and low birth weight (OR: 2.09; 95% CI: 1.41, 3.08). A U-shaped relation between weight change during pregnancy and preterm birth was observed. Severe anemia was significantly associated with fetal loss or stillbirth (OR: 3.67; 95% CI: 1.16, 11.66), preterm birth (OR: 2.08; 95% CI: 1.39, 3.10), low birth weight (OR: 1.76; 95% CI: 1.07, 2.90), and MTCT of HIV by the time of birth (OR: 2.26; 95% CI: 1.18, 4.34) and by 4-6 wk among those negative at birth (OR: 2.33; 95% CI: 1.15, 4.73).

CONCLUSIONS

Anemia, poor weight gain during pregnancy, and low BMI in HIV-infected pregnant women are associated with increased risks of adverse infant outcomes and MTCT of HIV. Interventions that reduce the risk of wasting or anemia during pregnancy should be evaluated to determine their possible effect on the incidence of adverse pregnancy outcomes and MTCT of HIV.

C-reactive protein independently predicts HIV-related outcomes among women and children in a resource-poor setting

OBJECTIVE

To evaluate C-reactive protein (CRP) as a predictor of HIV-related outcomes among women and children in a resource-poor setting.

DESIGN

We measured serum CRP concentration among 606 HIV-infected women, all of whom were not taking highly-active antiretroviral therapy, 3 to 11 months after they gave birth, and assessed relationships of CRP to HIV-related endpoints, including maternal disease progression, mother-to-child transmission of HIV, and maternal and child mortality.

METHODS

We used Cox proportional hazards and regression models adjusted for age, sociodemographic characteristics, anthropometric measurements, hemoglobin, CD4 cell count, HIV viral load, and, for child outcomes, breastfeeding status.

RESULTS

Ninety-four women had a high CRP concentration (> 10 mg/l). During the follow-up, 56 women progressed to WHO stage 4 and 188 died, and a high maternal CRP concentration was associated with a 2.26-fold [95% confidence interval (CI), 1.64-3.12] greater risk of progression to stage 4 or death. Among children, 174 acquired HIV and 116 died by age 2 years, and a high maternal CRP concentration was associated with a 3.03-fold (95% CI, 1.85-4.96) greater risk of child mortality. In multivariate analyses among adults, a high maternal CRP concentration was associated with a 1.55-fold (95% CI, 1.08-2.23) greater risk of progression to stage 4 or death. A maternal CRP concentration was not significantly associated with mother-to-child transmission of HIV.

CONCLUSIONS

A high maternal CRP concentration independently predicts HIV disease progression, maternal mortality, and child mortality in a resource-poor setting. C-reactive protein may be an important and inexpensive prognostic indicator for HIV-infected women and their children.

Micronutrients in HIV-positive persons receiving highly active antiretroviral therapy

In HIV-infected persons, low serum concentrations of vitamins and minerals, termed micronutrients, are associated with an increased risk of HIV disease progression and mortality. Micronutrient supplements can delay HIV disease progression and reduce mortality in HIV-positive persons not receiving highly active antiretroviral therapy (HAART). With the transition to more universal access to HAART, a better understanding of micronutrient deficiencies and the role of micronutrient supplements in HIV-positive persons receiving HAART has become a priority. The provision of simple, inexpensive micronutrient supplements as an adjunct to HAART may have several cellular and clinical benefits, such as a reduction in mitochondrial toxicity and oxidative stress and an improvement in immune reconstitution. We reviewed observational and trial evidence on micronutrients in HIV-positive persons receiving HAART to summarize the current literature and suggest future research priorities. A small number of observational studies have suggested that some, but not all, micronutrients may become replete after HAART initiation, and few intervention studies have found that certain micronutrients may be a beneficial adjunct to HAART. However, most of these studies had some major limitations, including a small sample size, a short duration of follow-up, a lack of adjustment for inflammatory markers, and an inadequate assessment of HIV-related outcomes. Therefore, few data are available to determine whether HAART ameliorates micronutrient deficiencies or to recommend or refute the benefit of providing micronutrient supplements to HIV-positive persons receiving HAART. Because micronutrient supplementation may cause harm, randomized placebo-controlled trials are needed. Future research should determine whether HAART initiation restores micronutrient concentrations, independent of inflammatory markers, and whether micronutrient supplements affect HIV-related outcomes in HIV-positive persons receiving HAART.

Vitamin supplements, socioeconomic status, and morbidity events as predictors of wasting in HIV-infected women from Tanzania

BACKGROUND

Wasting is a strong independent predictor of mortality in HIV-infected persons. Vitamin supplements delay the disease progression, but their effect on wasting is not known. Data are lacking on the risk factors for wasting in African HIV-infected persons.

OBJECTIVES

The objectives were to examine the effect of vitamin supplements on wasting in HIV-infected women and to assess the effects of sociodemographic characteristics, morbidity events, and immunologic progression on the risk of wasting.

DESIGN

HIV-infected women (n = 1078) from Tanzania were randomly assigned to receive 1 of 4 daily oral regimens: multivitamins (B complex, C, and E), vitamin A plus beta-carotene, multivitamins that included vitamin A plus beta-carotene, or placebo. The endpoints of the study included first episodes of a midupper arm circumference <22 cm or a body mass index (BMI; in kg/m2) <18 and the incidence of weight loss episodes during a median 5.3 y of follow-up.

RESULTS

Multivitamins alone significantly reduced the risk of a first episode of a midupper arm circumference <22 cm (relative risk: 0.66; 95% CI: 0.47, 0.94; P = 0.02). In multivariate-adjusted Cox models, the woman's age, education level, and height were inversely related to the incidence of wasting. Episodes of diarrhea, nausea or vomiting, lower respiratory tract infections, oral ulcers, thrush, severe anemia, and low CD4+ cell counts were each significantly related to an increased risk of wasting.

CONCLUSIONS

Vitamins C and E and the vitamin B complex have a protective effect on wasting in HIV-infected women. Prevention of diarrhea, severe respiratory tract infections, and anemia are likely to decrease the burden of wasting.

Potential Mechanisms for Altered Iron Metabolism in Human Immunodeficiency Virus Disease

Recently, anemia associated with human immunodeficiency virus (HIV) disease has received more attention as our understanding of the significance of anemia in this population has grown and more emphasis is placed on the quality of life of people living with HIV/AIDS. Although the diagnosis and treatment of anemia in HIV disease has been discussed in great detail, the prevalence and pathophysiology of the two most common forms of anemia, iron deficiency anemia (IDA) and the anemia of chronic disease (ACD), have not received much attention despite the difficulty and importance of differentiating between these two anemias. In addition, little attention has been given to iron overload, which has serious implications in individuals with HIV disease. This article proposes a model of altered iron metabolism in HIV disease as a basis for explaining the pathophysiology and implications of IDA, ACD, and iron overload in this population. Implications for clinical practice and recommendations for future research are discussed.

Serum albumin is a powerful predictor of survival among HIV-1-infected women

BACKGROUND

We previously reported that single measurements of albumin strongly predict survival in HIV-1-infected women independent of disease-specific markers. We now extend this to the use of serial measurements and single albumin values prior to initiation of highly active antiretroviral therapy.

DESIGN

Prospective cohort study of 1941 women enrolled at six sites in the Women's Interagency HIV Study.

RESULTS

Albumin fell 0.44 g/L/y in 1627 women who survived and at a faster rate in 397 who died (1.54 g/L/y; p <.01). In a time-dependent model adjusting for disease markers, the relative hazard (RH) was fivefold higher in patients with serum albumin <35 g/L compared with patients with serum albumin >42 g/L. The RH of serum albumin <35 g/L in women with CD4+ lymphocyte counts > or =200 cells/micro L was 8.2 [95% CI: 4.2-15.8]) versus only 3.8 [95% CI: 2.4-6.1] in those with counts <200 cells/mm3. In a fixed-covariate Cox analysis of patients who started HAART during the study, albumin prior to HAART was associated with a higher RH (7.0 for albumin <35 g/L versus >42 g/L) than were other factors.

CONCLUSION

Serum albumin is a strong independent predictor of mortality in HIV-1-infected women after adjustment for known disease markers and may be useful for clinical monitoring.

Pattern and predictors of weight gain during pregnancy among HIV-1-infected women from Tanzania

Progression of HIV disease is often accompanied by weight loss and wasting. Gestational weight gain is a strong determinant of maternal and neonatal outcomes; however, the pattern and predictors of weight gain during pregnancy among HIV-positive women are unknown. We obtained monthly anthropometric measurements in a cohort of 957 pregnant women from Tanzania who were HIV infected. We estimated the weekly rate of weight gain at various points during the second and third trimesters of pregnancy and computed rate differences between levels of sociodemographic, nutritional, immunologic, and parasitic variables at the first prenatal visit. The change in mid-upper arm circumference (MUAC) from baseline to delivery was also examined. The rate of weight gain decreased progressively during pregnancy. There was an average decline of 1 cm in MUAC between weeks 12 and 38. Lower level of education and helminthic infections at first visit were associated with decreased adjusted rates of weight gain during the third trimester. High baseline MUAC, not contributing to household income, lower serum retinol and selenium concentrations, advanced clinical stage of HIV disease, and malaria infection were related to decreased rates of weight gain during the second trimester. Low baseline CD4 T-cell counts were related to a poorer pattern of weight gain throughout pregnancy. Prevention and treatment of parasitic infections and improvement of nutritional status are likely to enhance the pattern of gestational weight gain among HIV-infected women.

Nutritional aspects of HIV-infected children receiving highly active antiretroviral therapy

The presentation of the nutritional problems of HIV-infected children is changing over time with improved antiretroviral regimens. Early reports of HIV infection in the 1980s, included such problems as malnutrition and wasting. However, as treatment and prophylactic regimens improve, the current nutritional problems of HIV-infected children in developed countries include truncal obesity and insulin resistance in addition to malnutrition. Background data on the wasting syndrome, etiology of malnutrition, nutritional effects of highly active antiretroviral therapies, and nutritional intervention strategies for HIV-infected children will be presented.

Distinguishing starvation from cachexia

The poor response to hypercaloric feeding in ill adults may be caused by failure to distinguish cachexia from starvation (Table 1). The chief difference between starvation and cachexia is that refeeding reverses starvation but is less effective for cachexia. The ineffectiveness of refeeding in treating cachexia may explain some of the poor results from direct nutritional interventions in clinical trials. Simple starvation should respond to voluntary or involuntary hypercaloric feedings. The failure to demonstrate a more positive response may be caused by underlying cachexic states.

Lipodystrophic syndromes and hyperlipidemia in a cohort of HIV-1-infected patients receiving triple combination antiretroviral therapy with a protease inhibitor

OBJECTIVES

To assess the frequency and features of lipodystrophic syndromes in HIV-1-infected patients receiving highly active antiretroviral therapy (HAART) with a protease inhibitor (PI), and examine whether clinical and biologic abnormalities are always associated in these conditions.

METHODS

Retrospective-prospective single-center observational study of 175 patients. Comparisons for continuous variables by t-test and paired t-test, and Kaplan-Meier analysis of time to onset of lipodystrophy were performed.

RESULTS

In all, 51 patients (29%) had morphologic changes, after a mean HAART duration of 20.0 +/- 6.1 months, and were categorized into pure lipoatrophy (n = 16), mixed syndrome (truncal fat accumulation and face or limb lipoatrophy) (n = 30) or pure truncal fat accumulation (n = 5). Because of the small number, the latter group was not analyzed statistically. No differences were found among patients with lipoatrophy, mixed syndrome, or no lipodystrophy, in terms of gender, CD4 count, and HIV RNA plasma load at time of HAART initiation, nor in response to treatment. Patients with a mixed syndrome were older. Patients with lipoatrophy had longer duration of HIV disease, pre-HAART exposure to nucleoside analog therapy, and HAART. Baseline and pre-HAART fasting triglyceride levels were higher in patients who developed lipoatrophy, whereas weight and fasting cholesterol were higher in patients who developed a mixed syndrome. After 12 and 24 months on HAART, triglycerides and cholesterol rose significantly in all patients, independently of lipodystrophy, whereas these parameters were not increased during nucleoside analog therapy.

CONCLUSIONS

Nucleoside analog exposure appears as a risk factor for lipoatrophy. Age and nutritional status (reflected by baseline weight, triglycerides and cholesterol) may influence the evolution to lipoatrophy or a mixed syndrome. Hyperlipidemia is observed in the absence of lipodystrophy and depends on PI exposure.

Urinary cytokines for assessing inflammation in HIV-associated wasting

The relationship between cytokines and HIV-related weight loss has not been well established. Unlike most cytokines that are secreted in a paracrine manner, IL-6, sTNFR-II, and IL-1ra are readily detected in the systemic circulation and serve as markers of the inflammatory response. Twenty-four-hour urine concentrations of these proteins are believed to provide an integrative assessment of their systemic levels over the preceding hours. We sought to determine whether spot measurements of IL-6, sTNFR-II, and IL-1ra could be related to subsequent 24 h concentrations and prior weight loss. Eighteen subjects with severe wasting (average BMI=18+/-3 kg/m2with 19+/-13 kg of weight loss) and six HIV-negative healthy subjects were tested. Compared to values in controls, 24-h urinary concentrations of the three proteins adjusted for creatinine excreted were elevated in 44%, 89%, and 72% of patients, respectively. Twenty-four-hour concentrations were highly correlated with the spot concentrations (r=0.80, 0.87, 0.84, respectively, P<0.001). IL-1ra concentrations (24 h and spot) were correlated with weight loss in the previous 6 months, lifetime rate of weight loss and the 6 month rate of weight loss (spot: r=0.66, 0.73, 0.68, respectively, P< or =0.001). These data suggest that spot urinary collections can be used to estimate 24 h excretion rates. This strategy may be useful in assessing the inflammatory response in HIV-associated wasting.

Association between high serum prolactin levels and concomitant infections in HIV-infected patients

Although prolactin (PRL) is now recognized as a cytokine and persistent immune activation is a common immunopathogenic feature of the human immunodeficiency virus infection (HIV), the circumstances associated with the onset of hyperprolactinemia during the course of this infection remain controversial. Given that PRL is able to exert not only endocrinologic effects but also immunologic influences, a study was conducted to investigate whether raised serum levels of PRL were more likely to prevail when HIV-infected patients developed concomitant infections. Serum PRL concentrations, as well as immunoglobulin isotypes, plasmatic viral burden, CD3+, CD4+, CD8+, CD19+, and natural killer (NK) cell counts were measured in 46 nonselected HIV-infected patients stratified on the basis of the presence or absence of clinically active concomitant infections. Serum PRL levels were significantly higher in patients presenting secondary infections as compared with the asymptomatic ones, with hyperprolactinemia being detected in 10/18 (55%) and 2/28 (7%) of these patient groups, respectively. Hyperprolactinemia was not related with viral burden, antiretroviral treatment, gender differences, or CD4+ cell counts. CD3+, CD4+, CD8+, and CD19+ cells were significantly lower in the group presenting active infections, whereas comparisons in NK cell counts, immunoglobulin levels and HIV viral burden revealed no differences between groups. These results provide evidence that hyperprolactinemia is more prevalent during the onset of secondary infections, which might have diagnostic and therapeutic consequences.

Ex vivo modulation of RANTES and sCD30 by proinflammatory stimuli in HIV-seropositive and -negative individuals

RANTES and sCD30 were measured in ex vivo culture supernatants of unstimulated or stimulated PBMC in order to investigate their potential role as markers of acute immune activation. Patients in an advanced stage of HIV infection (AIDS A) were compared to AIDS patients who were evaluated for pneumonia at the time of blood withdrawal (AIDS B); HIV(+) individuals with nonprogressive infection (LTNP) and healthy donors (N) served as controls. Constitutive levels of RANTES were significantly elevated in AIDS B patients (P 0.0001), whereas spontaneous release of sCD30 was strongly correlated with the presence of both pneumonia (P 0.002) and HIV infection (P 0.004). LPS was a strong inducer of RANTES in all four categories; however, in AIDS B patients a negative and positive correlation between constitutive and induced levels was observed with LPS (P 0.0004) and IFN-gamma (P 0.006), respectively. We clearly showed that IFN-gamma reached a fourfold superinduction of sCD30 release in both HIV-positive and -negative individuals, whereas IL-6-driven production of both sCD30 and RANTES occurred only in healthy donors. Ex vivo RANTES levels may also be monitored as an index of acute immune activation under conditions of chronic activation of the immune system, whereas sCD30 release may be equally indicative of both acute and chronic processes of T cell activation. Proinflammatory stimuli differentially affected RANTES and sCD30 secretion in ex vivo PBMC cultures, suggesting complex pathways in the in vivo regulation of these two molecules.

Interleukin-6 release by cultured peripheral blood mononuclear cells inversely correlates with height velocity, bone age, insulin-like growth factor-I, and insulin-like growth factor binding protein-3 serum levels in children with perinatal HIV-1 infection

Spontaneous and phytohemagglutinin (PHA)-stimulated interleukin (IL)-6 release by cultured peripheral blood mononuclear cells was related to height velocity, bone age, insulin-like growth factor-I (IGF-I), and IGF binding protein-3 (IGFBP-3) serum level standard deviation scores (SDS) of 32 children [aged 91 (median; range 13-151) months] with human immunodeficiency virus-type 1 (HIV-1) perinatal infection and severe disease. Spontaneous and PHA-stimulated IL-6 release inversely correlated with height velocity, bone age, IGF-I, and IGFBP-3 SDS. Ten children with height velocity SDS </= -2, compared to 22 children with height velocity SDS > -2, showed higher spontaneous and PHA-stimulated IL-6 release and lower IGF-I and IGFBP-3 SDS (irrespective of CD4-positive T-lymphocyte counts, viral load, liver disease, or nutrition status). IL-6 overproduction may be a mechanism of IGF-I and IGFBP-3 down-regulation and impaired linear growth in children with perinatal HIV-1 infection. Growth-promoting strategies, including targeted anticytokine treatments, could be devised for such children.

Soluble tumor necrosis factor receptors in chronic hepatitis C: a correlation with histological fibrosis and activity

BACKGROUND/AIMS

Tumor necrosis factor-alpha (TNF) is a mediator of inflammation and cellular immune response. Soluble TNF receptors (sTNFR) sTNF-R55 and sTNF-R75, which compete with cellular receptors for the binding of TNF, have been detected at high levels in infectious diseases including human immunodeficiency virus and HBV infection. In order to investigate the activation of the TNF system in HCV infection, we have analyzed the balance between TNF and sTNF-R in 60 HCV-infected subjects according to their clinical, biological, virological and histological characteristics.

METHODS

Serum TNF, sTNF-R55 and sTNF-R75 levels were determined by ELISA before any therapy and were compared to a control group of 60 healthy subjects and a group of 34 HBV-infected patients.

RESULTS

Mean TNF levels were 50.5+/-4.5 pg/ml in HCV patients, and undetectable (<5 pg/ml) in the control subjects. sTNF-R55 and sTNF-R75 levels were significantly higher in HCV-infected patients than in the controls: 2.88+/-0.14 ng/ml vs. 1.30+/-0.05, (p = 0.0001), and 9.54+/-0.58 ng/ml vs. 4.19+/-016, (p = 0.0001), respectively. sTNF-R55 and TNF-alpha levels in HCV patients were not significantly different from levels in HBV patients. sTNF-R75 levels were slightly lower than in HBV patients (9.54+/-0.58 vs. 11.4+/-0.79 ng/ml, p = 0.03). In contrast to other infectious diseases, there was no correlation between levels of sTNF-R and TNF. sTNF-R75 but not TNF levels were correlated with aminotransferases levels (p = 0.0001 and p = 0.0015 for aspartate and alanine aminotransferase, respectively), while sTNF-R55 levels were significantly correlated only with aspartate aminotransferase levels (p = 0.003). sTNF-R75 levels were significantly correlated with the Metavir activity index (p = 0.01), and sTNF-R55 and sTNF-R75 levels were significantly higher in patients with vs. without cirrhosis (3.22+/-0.21 vs. 2.54+/-0.17 ng/ml (p<0.02) and 11.6+/-0.86 vs. 7.5+/-0.53 ng/ml (p<0.001), respectively). sTNF-R55, sTNF-R75 and TNF levels were not correlated with viral load, genotype or response to interferon therapy.

CONCLUSIONS

Levels of soluble TNF receptors, and particularly sTNF-R75, are significantly correlated with the severity of the disease but not with virological parameters such as quantitative viremia and genotype. High TNF-R production could thus suggest that HCV-related liver disease involves immunological mechanisms, including activation of the TNF system.

HIV infection and malnutrition

Weight loss, anorexia, metabolic disorder and malabsorption are leading symptoms of HIV infection. Recent data help us to understand wasting as being intrinsically linked to immunodysregulation and enteropathy. In therapy, the role played by anabolic steroids and growth hormone has been newly defined. The new antiviral drugs may efficiently prevent clinical progression, including wasting. New metabolic side effects have, however, been encountered.

Serum levels of beta2-microglobulin, neopterin, TNF-alpha and soluble receptors of TNF-alpha and interleukin-2 in intravenous drug abusers according to HIV-1 status and stage of the HIV-1 infection

OBJECTIVE: To compare the serum levels of beta2-microglobulin (beta2M), neopterin (NP), TNF-alpha and soluble receptors of TNF-alpha (sTNF-R55 and sTNF-R75) and interleukin-2 (sIL-2R) in a population of intravenous drug abusers according to whether or not they had HIV-1 infection and to the stage of the HIV-1 infection. METHODS: A cross-sectional study was performed at four drug detoxification centers in Barcelona, and the HIV outpatient clinic at Hospital Clínic in Barcelona. Three cohorts of intravenous drug abusers (IVDAs)-105 HIV-1-uninfected patients (cohort A), 174 with asymptomatic HIV-1 infection (cohort B) and 39 with AIDS (cohort C)-were enrolled. On the first visit, the following laboratory tests were performed: hemogram and platelet count, hepatitis B surface antigen (HBsAg), anti-hepatitis C antibodies, B2M, NP, sIL-2R, TNF-alpha, and TNF receptors (sTNF-R55 and sTNF-R75). RESULTS: The three cohorts were homogeneous according to sex, type of drug, average number of intravenous doses of drug in 1 day, and hepatitis B infection. Patients with AIDS were older than those of cohort A and B (p<0.0001). HIV-negative IVDAs were co-infected with hepatitis C virus less frequently than were HIV-positive IVDAs (80% versus 91%, p<0.03). Among HIV-1-negative IVDAs (cohort A), almost all (from 86% to 95%, depending on the marker) individual values were within the normal boundaries of our laboratory. With a single exception (level of sTNF-R55 in cohort B compared with cohort A, p=0.15), levels of all markers were significantly higher in asymptomatic HIV-1-infected (cohort B) when compared with uninfected patients (cohort A), and in AIDS patients (cohort C) when compared with both cohorts A and B. There was a significant positive correlation between levels of ss2M and NP (r=0.56; p<0.01), ss2M and TNF (r=0.65, p<0.01) and NP and TNF (r=0.76, p<0.01). There was no correlation between levels of sIL-2R and levels of ss2M, NP or TNF and its receptors. CONCLUSIONS: Intravenous drug abuse does not modify serum levels of ss2M, NP, sIL-2R, TNF-alpha, and TNF receptors (sTNF-R55 and sTNF-R75). Levels of these markers increase significantly when an HIV-1 infection occurs and when there is progression to AIDS.

Imbalance between IL-1 and IL-1 receptor antagonist in the cerebrospinal fluid of HIV-infected patients

Inflammatory cytokines (interleukin [IL]-1 and tumor necrosis factor [TNF]) have specific inhibitors (IL-1 receptor antagonist [IL-1Ra] and TNF-soluble receptors), the concentration of which can indicate activation and regulation of this system. We measured IL-1 and IL-1Ra in the cerebrospinal fluid (CSF) of HIV-infected patients and seronegative controls. High IL-1Ra concentrations were found in samples from patients with opportunistic meningoencephalitis, even in the presence of normal cell count and protein content, not in samples from patients with leucoencephalopathies or controls. Therefore, IL-1Ra appears to be a sensitive marker of inflammation in the central nervous system. In contradistinction to previous results obtained from blood measurement, IL-1alpha and IL-1beta remained below detectable levels in all cases, suggesting that IL-1 may be regulated differently in the central nervous system and in the blood.

Death of Bystander Cells by a Novel Pathway Involving Early Mitochondrial Damage in Human Immunodeficiency Virus–Related Lymphadenopathy

Destruction of immune cells in peripheral lymphoid tissues plays presumably a pivotal role in acquired immune deficiency syndrome pathogenesis. We found that cell suspensions obtained from lymph nodes of eight human immunodeficiency virus (HIV)-infected individuals contained variable proportions (2.1% to 18.3%, median 11.2%) of dead lymphocytes permeable to supravital dyes, represented by CD4+, CD8+, and B cells. The frequency of dead cells correlated directly (R = 0.847) with the amount of HIV provirus in the cell populations, and HIV provirus was enriched in the dead cell fractions. Similar proportions of dead cells were observed in cell suspensions from lymphadenopathic lymph nodes of HIV− donors, but not from small resting HIV− lymph nodes. Electron microscopic and flow cytometric analyses revealed that most dead cells from HIV+ lymph nodes lacked internucleosomal DNA fragmentation but displayed combined features of apoptosis and necrosis, eg, chromatin condensation and mitochondrial swelling. Cells with similar morphology were readily identified in lymph node tissue sections, and marked mitochondrial swelling could be occasionally observed in cells with otherwise normal morphology. Our findings have two major implications. One is that the in vivo cell death in HIV-infected lymph nodes occurs predominantly through a novel pathway, related to but distinct from classical apoptosis and characterised by early and severe mitochondrial damage. The second implication is that HIV-related lymphadenopathy is accompanied in vivo by massive destruction of uninfected lymph node cells. Comparable levels of cell death were observed in other inflammatory lymphadenopathies not related to HIV; however, the uniquely endless and generalized nature of HIV lymphadenopathy might render this “inflammatory” cell destruction a powerful pathogenetic mechanism, accounting for the progressive disruption and depletion of lymphoid tissues seen in HIV infection.

Death of Bystander Cells by a Novel Pathway Involving Early Mitochondrial Damage in Human Immunodeficiency Virus–Related Lymphadenopathy

Destruction of immune cells in peripheral lymphoid tissues plays presumably a pivotal role in acquired immune deficiency syndrome pathogenesis. We found that cell suspensions obtained from lymph nodes of eight human immunodeficiency virus (HIV)-infected individuals contained variable proportions (2.1% to 18.3%, median 11.2%) of dead lymphocytes permeable to supravital dyes, represented by CD4+, CD8+, and B cells. The frequency of dead cells correlated directly (R = 0.847) with the amount of HIV provirus in the cell populations, and HIV provirus was enriched in the dead cell fractions. Similar proportions of dead cells were observed in cell suspensions from lymphadenopathic lymph nodes of HIV− donors, but not from small resting HIV− lymph nodes. Electron microscopic and flow cytometric analyses revealed that most dead cells from HIV+ lymph nodes lacked internucleosomal DNA fragmentation but displayed combined features of apoptosis and necrosis, eg, chromatin condensation and mitochondrial swelling. Cells with similar morphology were readily identified in lymph node tissue sections, and marked mitochondrial swelling could be occasionally observed in cells with otherwise normal morphology. Our findings have two major implications. One is that the in vivo cell death in HIV-infected lymph nodes occurs predominantly through a novel pathway, related to but distinct from classical apoptosis and characterised by early and severe mitochondrial damage. The second implication is that HIV-related lymphadenopathy is accompanied in vivo by massive destruction of uninfected lymph node cells. Comparable levels of cell death were observed in other inflammatory lymphadenopathies not related to HIV; however, the uniquely endless and generalized nature of HIV lymphadenopathy might render this “inflammatory” cell destruction a powerful pathogenetic mechanism, accounting for the progressive disruption and depletion of lymphoid tissues seen in HIV infection.