Plasma concentrations of soluble Fas receptors (Fas) and Fas ligands (FasL) in relation to CD4+ cell counts in HIV-1 positive and negative patients in Yaounde, Cameroon.
BACKGROUND
Though documented that HIV infection progresses with the depletion of CD4+ cells, the exact mechanisms by which these cell depletions occur are not clearly understood. This study aimed at evaluating the plasma levels of soluble Fas receptors and ligands in HIV-infected and uninfected patients in Yaounde, Cameroon, a population with a known diversity of HIV in whom this has not been previously assessed.


RESULTS
In a cross-sectional study, 39 antiretroviral naïve HIV-1 positive and negative participants were recruited in Yaounde, Cameroon. CD4+ lymphocyte cell counts were quantified from whole blood using an automated FACScount machine (Becton-Dickinson, Belgium). Plasma samples obtained were analyzed for soluble Fas receptors and Fas ligands in both HIV-1 positive and negative samples using two different quantitative sandwich ELISA kits (Quantikine®, R&D Systems , UK).Plasma levels of Fas receptors were higher in HIV-1 positive patients (median = 1486pg/ml IQR = 1193, 1830pg/ml) compared to HIV-negative controls (median = 1244pg/ml, IQR = 1109, 1325pg/ml), p-value <0.001. Plasma levels of Fas ligands were also higher in HIV-1 positive patients (median = 154pg/ml, IQR = 111, 203pg/ml) compared to HIV-negative controls (median = 51pg/ml, IQR = 32, 88pg/ml), p-value = 0.005. Plasma concentrations of soluble fas receptors and ligands tended to be negatively correlated with the CD4+ cell counts of HIV-positive patients; the correlation coefficients were -0.34 (value = 0.78) and-0.3 (p-value = 0.51) respectively.


CONCLUSIONS
In this population of patients in Cameroon, plasma concentrations of Fas receptors and Fas ligands tend to be higher in HIV-positive patients. The Fas pathway of apoptosis may have a role in the depletion of CD4+ cell counts.
Center for the Study and Control of Communicable Diseases (CSCCD), Faculty of Medicine and Biomedical Sciences, University of Yaoundé 1, Yaoundé, Cameroon. gikomey@yahoo.com
George M
GM
Ikomey
Marie-Claire
MC
Okomo-Assoumou
Julius
J
Atashili
Martha T
MT
Mesembe
Bertha
B
Mukwele
Emilia
E
Lyonga
Agnes
A
Eyoh
Peter M
PM
Ndumbe
D015415:Biomarkers / Q000097:blood; D018791:CD4 Lymphocyte Count; D002163:Cameroon / Q000453:epidemiology; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D018450:Disease Progression; D004797:Enzyme-Linked Immunosorbent Assay; D053222:Fas Ligand Protein / Q000097:blood*; D005260:Female; D015658:HIV Infections / Q000097:blood / Q000175:diagnosis* / Q000276:immunology / Q000821:virology; D015497:HIV-1 / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D011379:Prognosis; D011933:Reagent Kits, Diagnostic; D015854:Up-Regulation; D019014:fas Receptor / Q000097:blood*
D015415:Biomarkers; C491901:FAS protein, human; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D011933:Reagent Kits, Diagnostic; D019014:fas Receptor