Host genetic factors such as MBL2 gene polymorphisms cause defects in the polymerization of MBL protein and result in a functional deficiency and / or in low serum levels that influence susceptibility to various viral infections.
The aim of this study was to estimate the frequency of alleles, genotypes and haplotypes related to -550, -221 and exon 1 polymorphisms of the MBL2 gene and to investigate their association with HHV-8 in people living with HIV / AIDS (PLWHA) , as well as the CD4 cell count and HIV viral load in HIV / HHV-8 coinfected and HIV monoinfected patients.
A cross sectional study in PLWHA , with and without HHV-8 infection, exploring associations between different factors, was performed in the outpatient infectious and parasitic diseases clinic at a referral hospital.
Genomic DNA extractions
Genomic DNA extractions from leukocytes were performed using a commercial Wizard ® Genomic DNA Purification kit (Promega, Madison, WI). The promoter region (-550 and -221) was genotyped With the TaqMan system (Applied Biosystems TaqMan ® Genotyping Assays), and the structural region (exon1) was genotyped With Express Sybr Greener Supermix kit (Invitrogen, USA).
In total, 124 HIV/HHV-8 coinfected and 213 HIV monoinfected patients were analysed. Median TCD4 counts were significantly lower in HIV/HHV-8 coinfected patients, whereas the mean of the first and last viral load of HIV did not present significant difference.
HIV infected patients
There was no difference in frequency between the LL, YY and AA genotypes between the HIV/HHV-8 coinfected or HIV monoinfected patients. However, in a multivariate analysis, coinfected patients with the intermediate expression haplotype of the MBL2 gene had an odds ratio of 3.1-fold (CI = 1.2–7.6) of their last CD4 cell count being below 350 cells/mm3.
Among the coinfected individuals, four developed KS and presented the intermediate expression MBL haplotype , with three being HYA / LXA and one being LYA / LYO.
Host genetic factors , such as -550, -221 and exon 1 polymorphisms, may be related to the may modify coinfections and / or to the clinical development manifestations caused by HHV-8, especially in HIV / HHV-8 coinfected patients who presented the intermediate expression haplotypes of MBL.
The results of our research showed that the median of the first TCD4 cell count was lower in patients with monoinfected patients with a statistically significant difference. However, another study has shown that HHV-8 has little influence on HIV progression in initially asymptomatic individuals, with little repercussion in TCD4 cell count.
Nonetheless, considering that the study was a cross section of PLWHA , with or without HHV-8 infection, it was not possible to identify the moment of HHV-8 seroconversion, because it was not observational cohort study. Highlighting the importance of more specific studies with HIV / HHV-8 coinfected patients.