Natural immunity and HIV disease progression

Area of Science:

• Immunology
• Virology
• Clinical Medicine

Background:

• Natural immunity, mediated by natural killer (NK) and lymphokine-activated killer (LAK) cells, plays a crucial role in controlling viral infections.
• Human immunodeficiency virus type 1 (HIV-1) infection is known to impair immune function, but the specific role of NK and LAK cells in disease progression requires further investigation.

Purpose of the Study:

• To investigate the clinical implications of impaired natural killer (NK) and lymphokine-activated killer (LAK) cell activity in individuals with HIV-1 infection.
• To determine the prognostic value of NK and LAK cell activity for disease progression and survival in HIV-1-infected patients.

Main Methods:

• Prospective follow-up of 172 individuals with HIV-1 infection, assessing NK and LAK cell activity, CD4 T cell counts, and CD16/CD56 NK cell concentration at enrollment.
• Retrospective measurement of plasma HIV RNA and survival analysis for endpoints including CD4 counts < 100 cells/µL, clinical AIDS, and death.

Main Results:

• Low LAK cell activity was significantly associated with an increased risk of progression to CD4 counts < 100 cells/µL and a higher risk of death, even after adjusting for baseline covariates.
• Low NK cell responsiveness to interferon-alpha showed a trend towards increased risk of death, while unstimulated NK cell activity and NK cell concentration had no prognostic value.

Conclusions:

• Impaired LAK cell activity is a significant predictor of poorer clinical outcomes in HIV-1 infection.
• Reduced NK cell responsiveness to interferon-alpha may also contribute to disease progression and mortality in HIV-1-infected individuals.