Impaired development of HIV-1 gp160-specific CD8(+) cytotoxic T cells by a delayed switch from Th1 to Th2 cytokine phenotype in mice with Helicobacter pylori infection

Eradication of Helicobacter pylori can facilitate immune reconstitution in HIV-1-infected immunological non-responders

OBJECTIVE

A significant number of HIV-1 patients experience poor immune reconstitution despite long-term viral suppression with highly active antiretroviral therapy (immunological non-responders). The aims of the present study were to determine whether eradication of Helicobacter pylori could facilitate a better immune reconstitution in these patients.

METHODS

Forty-nine immunological non-responder HIV-1 patients were evaluated by (13)C-urea breath test (UBT) for the presence of active H. pylori infection. They were all asymptomatic. The UBT was positive in 26 (53%) of them. Eleven patients (group 1) were treated with a combination of omeprazole 20mg bid, amoxicillin 1g bid and clarithromycin 500mg bid for 14 consecutive days. Eight weeks later, successful eradication was proven by a repeat negative UBT in all 11 patients. The remaining 15 (group 2) refused the H. pylori eradication treatment. All 26 patients were followed for 24 months and evaluated for blood CD4 and CD8 cell counts and percentages and for plasma HIV-1 viral load.

RESULTS

At the time of H. pylori diagnosis and eradication (baseline), CD4 and CD8 cell counts were similar in both study groups. All 11 H. pylori eradicated patients (group 1) had a significant increase in CD4 cell count starting 3 months and peaking 12-18 months after H. pylori eradication. Thereafter, CD4 levels gradually declined. Nevertheless, 24 months after triple therapy it was significantly higher than prior to H. pylori eradication. Parallel reciprocal changes were observed in CD8 cell counts. There were no significant changes in either CD4 or CD8 cell counts in group 2 patients. None of the patients of group 1 demonstrated virological failure, while four (26.7%) group 2 patients experienced virological failure requiring change of highly active antiretroviral therapy (HAART) regimen.

CONCLUSION

Triple therapy for H. pylori eradication is associated with a significant, although possibly transient immune reconstitution in HAART-treated HIV-1 patients with viral suppression without immunological response.

Cytokine profile in response to Cytomegalovirus associated with immune recovery syndrome after highly active antiretroviral therapy

BACKGROUND

Several changes have occurred in the presentation and course of cytomegalovirus (CMV) retinitis in patients with AIDS since the introduction of HAART (highly active antiretroviral therapy). In some individuals who take HAART, retinitis is kept under control even after the discontinuation of anti-CMV therapy. However, many of these patients develop intraocular inflammation. Uveitis, cataract, vitreitis, cystoid macular edema, epiretinal membrane, and disc edema may occur in patients with immune recovery syndrome (IRS).

METHODS

We evaluated the CMV-specific immune response in 55 patients by assessing CMV-specific lymphocyte proliferation, cytotoxicity, and cytokine production and correlated it with the clinical outcome.

RESULTS

Our data suggest that control of CMV retinitis is associated with acquisition of cytotoxic and lymphoproliferative responses to CMV. In addition, the upsurge of macular and disc edema seems associated with the production of interleukin-4 and tumor necrosis factor-alpha, whereas vitreitis is associated with the production of interleukin-2 and interferon-gamma.

INTERPRETATION

The type of T-cell response that develops after HAART may determine the side effects of immune recovery and these effects are predictable based on the lymphokine profile produced by CMV-specific cells.