The effect of human leukocyte antigen G alleles on human papillomavirus infection and persistence in a cohort of HIV-positive pregnant women from Brazil

- HLA-G alleles have been associated with HPV pathogenesis and persistence in women.
- HIV infection and pregnancy are linked to HPV infection and cervical lesions.
- We found no HLA-G alleles associated with protection against HPV infection.
- HLA-G:01:01:02 was protective to the occurrence of lesions in HPV patients.
- Four novel HLA-G alleles were described in our study, one of them in four patients.

Patients with compromised immune systems have more severe intraepithelial lesions and more rapid disease progression, in addition to increased risk for cervical cancer. Persistent infection by the human papillomavirus (HPV) is a necessary step in that process. By inducing expression of inhibitory ligands of natural killer cells, like HLA-G, HPV avoids the elimination of infected cells. Recent studies have investigated polymorphisms in HLA-G that may be associated with susceptibility to HPV infection and persistence. One hundred-forty HIV+ pregnant women from Brazil had a DNA fragment comprising HLA-G exons 2-4 PCR-amplified, cloned, sequenced and analyzed for allele determination. Altogether, 22 alleles comprising 52 different genotypes were found. Four novel HLA-G alleles were characterized. We have not observed association of specific HLA-G alleles with HPV infection, but found a protective effect of the G:01:01:02 allele against the occurrence of intraepithelial lesions. In addition to describing new HLA-G alleles and defining new reference sequences, our data provide a better understanding of the impact of HLA-G alleles on HPV-related disease.