Impaired phagolysosomal fusion of peripheral blood monocytes from HIV-infected subjects.
We evaluated phagolysosomal fusion in peripheral blood monocytes from 20 HIV-infected individuals and 40 normal controls, using a fluorescence assay with acridine orange as marker. The percentages of phagolysosomal fusion of monocytes from HIV-infected subjects, after 30 and 60 min of yeast ingestion, (mean +/- standard deviation) 57.2 +/- 17 and 63.2 +/- 18.6, respectively, when compared to normal controls (72.4 +/- 7.8 and 77 +/- 8.1), did not differ significantly. However, there was a direct linear association between the percentages of phagolysosomal fusion and CD4+ lymphocytes (P < 0.001) or CD4/CD8 T-cell ratio (P < 0.01). These results suggest that phagolysosomal dysfunction becomes evident at late stages of HIV infection and progresses as CD4+.T-lymphocyte count and CD4/CD8 T-cell ratio decrease. On the other hand, recombinant gp120 inhibited significantly normal phagolysosomal fusion at concentrations ranging between 1 and 1000 ng/ml. Taking together the results obtained, we can conclude that gp120 could be responsible for monocyte phagolysosomal dysfunction observed in HIV infected patients.
Pittis
M G
MG
Instituto de Investigaciones Hematológicas Mariano R. Castex, Academia Nacional de Medicina, Buenos Aires, Argentina.
Sternik
G
G
Sen
L
L
Diez
R A
RA
Planes
N
N
Pirola
D
D
Estevez
M E
ME
D000328:Adult; D016516:CD4-CD8 Ratio; D002459:Cell Fusion; D005260:Female; D015699:HIV Envelope Protein gp120 / Q000494:pharmacology; D015658:HIV Infections / Q000097:blood* / Q000473:pathology; D015497:HIV-1; D006801:Humans; D008247:Lysosomes / Q000473:pathology / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000502:physiology*; D010587:Phagocytosis; D010588:Phagosomes / Q000473:pathology / Q000502:physiology*; D011994:Recombinant Proteins / Q000494:pharmacology
D015699:HIV Envelope Protein gp120; D011994:Recombinant Proteins