Presence of HIV DNA in neutrophils: relationship to their functional activity

The role of phagocytes in HIV-related oxidative stress

BACKGROUND

in response to a variety of stimuli, phagocytes release large quantities of reactive oxygen species (ROS), which are essential for bacterial killing. However, excessive ROS production not appropriately compensated by antioxidant molecules can lead to oxidative stress, which may also play an important role in pathogenesis of HIV infection. In fact, ROS participate in chronic inflammation, HIV replication and the apoptosis of cells of the immune system.

OBJECTIVE AND STUDY DESIGN

we used flow cytometry to study, in whole blood, the activation and redox status of polymorphonuclear neutrophils (PMN) and monocytes at different stages of the disease.

RESULTS

we showed that neutrophils and monocytes from HIV-infected patients spontaneously produced increased amounts of H2O2. This increased H2O2 production was associated with alterations of adhesion molecules expression at the cell surface, which also reflected basal activation of phagocytes from the HIV-infected patients. In monocytes, basal H2O2 production correlated with viral load. This increased ROS production was associated with changes in the expression of the antiapoptotic/antioxidant compounds Bcl-2 and thioredoxin along the course of the disease. This modulation could result from a dual regulation by oxidative stress and could explain at least in part why monocyte numbers remain relatively stable throughout the disease. Monocytes expressed a normal maximal capacity to produce ROS in optimal conditions of stimulation. In contrast, after ex vivo priming with TNFalpha or IL-8, neutrophils showed a decreased H2O2 production in response to bacterial N-formyl peptides. This latter impairment correlated with the decrease in CD4+ lymphocyte numbers and with IL-8 and IL-6 plasma levels.

CONCLUSIONS

the increased basal ROS production by phagocytes could participate to the oxidative injury which has been implicated in the pathophysiology of HIV infection. In addition, the decreased priming of H2O2 production by neutrophils could contribute to the increased susceptibility of HIV-infected patients to bacterial infections.

Cutaneous findings in HIV-1-positive patients: a 42-month prospective study. Military Medical Consortium for the Advancement of Retroviral Research (MMCARR)

BACKGROUND

Cutaneous disease is common in patients infected with HIV-1.

OBJECTIVE

The aim of our study was to identify cutaneous markers associated with HIV-1 infection and disease progression as measured by Walter Reed (WR) stage.

METHODS

For 42 months we have observed 912 HIV-1-positive patients in all WR stages. All patients had an extensive past and present medical history taken as well as a complete physical examination, periodic visits, and appropriate diagnostic procedures.

RESULTS

Increasing dryness of the skin and seborrheic dermatitis are early findings in a large percentage of patients in WR stage 1; the occurrence and severity of both conditions increase with disease progression. Tinea infections, condylomata acuminata, and verrucae are seen early, but with disease progression, although there is no clear increase in occurrence, these infections become more diffuse and resistant to treatment. Flares in acne vulgaris and folliculitis show a peak occurrence in early and mid-stage disease with a decreased occurrence in late-stage disease. Herpes simplex infections, oral candidiasis, molluscum contagiosum, Staphylococcus aureus infections, and oral hairy leukoplakia show a marked increase in occurrence with advanced disease. Conditions that have a statistically significant association with disease progression as measured by a change in a stage include drug eruptions, seborrheic dermatitis, oral candidiasis, oral hairy leukoplakia, molluscum contagiosum, herpes zoster, and hyperpigmentation (nail, oral, skin).

CONCLUSION

The most frequent and persistent cutaneous disorders were asteatosis (with or without asteatotic eczema) and seborrheic dermatitis. Conditions that were associated with a change in WR stage include drug eruptions, seborrheic dermatitis, oral candidiasis, oral hairy leukoplakia, molluscum contagiosum, herpes zoster, and hyperpigmentation. In addition to Kaposi's sarcoma, patients with HIV-1 disease have an increased potential for the development of both cutaneous epithelial and probably melanocytic malignancies. Epithelial tumors were seen in patients in all stages of disease.

Mononuclear cells from HIV-infected patients produce factors which enhance functional activity of polymorphonuclear neutrophils from healthy subjects

The influence of mononuclear cell supernatants (MNCS) from nine healthy donors and 35 HIV-infected patients (17 with lymphoadenopathy syndrome (LAS), 15 with ARC and three with AIDS) on functional activity of polymorphonuclear neutrophils (PMN) from healthy donors was investigated. MNC after short-term cultivation (24 h) produced factors which enhanced chemiluminescence (CL) and chemotaxis of PMN. This augmentation did not depend on stimulation of MNC by mitogens (lipopolysaccharide Escherichia coli (LPS) and concanavalin A (Con A)) or on activation of PMN by FMLP. After 48 h of cultivation only MNC stimulated by LPS produced these factors. MNCS from HIV-infected patients provoked a more pronounced augmentation of PMN CL compared with MNCS from healthy subjects. This enhancement was observed in patients at all stages of infection, but was more pronounced in patients with LAS. MNCS impact on PMN CL was not connected with proliferative activity of MNC but was correlated with the level of CD4 cells. It was shown that removal of adherent cells from MNC fraction resulted in decreased MNCS impact. Treatment of MNCS by antibody to IL-1 beta, IL-8, interferon-alpha (IFN-alpha) and tumour necrosis factor-alpha (TNF-alpha) did not decrease MNCS impact on PMN CL.