CORRELATION OF THE SUPPRESSIVE ACTIVITY OF A BIOLOGICAL RESPONSE MODIFIER ON THE PROLIFERATION OF PERIPHERAL-BLOOD MONONUCLEAR-CELLS AND THE REDUCTION OF HIV TITER
Lm. Vila et al., CORRELATION OF THE SUPPRESSIVE ACTIVITY OF A BIOLOGICAL RESPONSE MODIFIER ON THE PROLIFERATION OF PERIPHERAL-BLOOD MONONUCLEAR-CELLS AND THE REDUCTION OF HIV TITER, Cellular and molecular biology, 43(7), 1997, pp. 981-988
Activation of CD4+ cells is a prerequisite for infection by the human
immunodeficiency virus (HIV). Thus, any agent capable of suppressing C
D4+ cell proliferation could create a refractory stage that would impe
de viral infection. We have reported, in a previous publication, that
a biological response modifier (BRM), polyantigenic immunomodulator (P
AI) substantially reduces HIV-1 titer (from 20 to 100%) in peripheral
mononuclear cells (PBMC) cultures with high viral titer (p24 = 10(2)-1
0(5) pg/ml). We are presenting data suggesting that the reported reduc
tion in virus titer seems to be associated with a suppressive activity
of PAI on the proliferation of PBMC from intravenous drug users (IVDU
) infected and non-infected with HIV-1. PAI, a well characterized BRM,
is a mixture of inactivated bacterial and influenza virus vaccines. P
BMC from healthy donors and IVDU individuals were exposed to PAI, phyt
ohemagglutinin (PHA), interleukin-2 (IL-2) and to combinations of PAI
with either PHA or IL-2. Appropriate controls were included. H-3-thymi
dine pulsing was used as indicator of cell proliferation. The stimulat
ion index and the difference between mean cpm of test sample and contr
ol were used to measure proliferative activity. There was a low prolif
erative response in the PBMC cultures from IVDU and HIV-1 positive pat
ients, but it was substantially lower in the later group. When PBMC cu
ltures from the same group of individuals were exposed to PAI, PHA and
IL-2, and to the combination of either PAI plus PHA or IL-2, the resp
onse observed in the PAI treated group was uniformly lower than in the
other treated cultures. Moreover, when PAI was combined with PHA, it
exerted a significant reduction in the measured parameters. The effect
of PAI on IL-2 activity was negligible. A suppressive effect of a PAI
has been detected on the proliferation of PBMC from IVDA and HIV-1 po
sitive individuals. This activity may be associated with the capacity
of PAI to reduce HIV titers in infected PBMC cultures.