INCREASED PRODUCTION OF NITRIC-OXIDE CORRELATES WITH VIRAL LOAD AND ACTIVATION OF MONONUCLEAR PHAGOCYTES IN HIV-INFECTED PATIENTS

The objective of our study was to determine the production of nitric o xide (NO) in patients infected with human immunodeficiency virus (HIV) and its relation to cellular immunity, activation of mononuclear phag ocytes and the amount of circulating virus. Therefore, serum nitrate, the stable metabolite of NO, the number of peripheral CD4(+) T-lymphoc ytes, serum neopterin, plasma HIV-RNA and HIV-DNA in peripheral blood mononuclear cells of afebrile HIV-infected patients were determined. S erum nitrate levels were significantly (p=0.002) increased in HIV-infe cted patients (median 37 mu M, range 13-137 mu M, (n=77) in comparison to healthy subjects (median 28 mu M, range 21-40 mu M, n=17). Serum n itrate levels did not correlate with the number of CD4(+) T-lymphocyte s (r=0.05, p > 0.05). Serum nitrate levels were positively correlated with neopterin (r=0.36, p=0.05, n=30), the amount of HIV-DNA in periph eral blood mononuclear cells (r=0.63, p < 0.001, n=27) and plasma HIV- RNA levels (r=0.35, p=0.08, n=27). A possible explanation of our findi ngs is that HIV induces the production of NO by means of activated mon onuclear phagocytes.