RESUMO
Human endogenous retroviruses (HERVs) arise from ancient infections of the host germline cells by exogenous retroviruses, constituting 8% of the human genome. Elevated level of envelope transcripts from HERVs-W has been detected in CSF, plasma and brain tissues from patients with Multiple Sclerosis (MS), most of them from Xq22.3, 15q21.3, and 6q21 chromosomes. However, since the locus Xq22.3 (ERVWE2) lack the 5' LTR promoter and the putative protein should be truncated due to a stop codon, we investigated the ERVWE2 genomic loci from 84 individuals, including MS patients with active HERV-W expression detected in PBMC. In addition, an automated search for promoter sequences in 20 kb nearby region of ERVWE2 reference sequence was performed. Several putative binding sites for cellular cofactors and enhancers were found, suggesting that transcription may occur via alternative promoters. However, ERVWE2 DNA sequencing of MS and healthy individuals revealed that all of them harbor a stop codon at site 39, undermining the expression of a full-length protein. Finally, since plaque formation in central nervous system (CNS) of MS patients is attributed to immunological mechanisms triggered by autoimmune attack against myelin, we also investigated the level of similarity between envelope protein and myelin oligodendrocyte glycoprotein (MOG). Comparison of the MOG to the envelope identified five retroviral regions similar to the Ig-like domain of MOG. Interestingly, one of them includes T and B cell epitopes, capable to induce T effector functions and circulating Abs in rats. In sum, although no DNA substitutions that would link ERVWE2 to the MS pathogeny was found, the similarity between the envelope protein to MOG extends the idea that ERVEW2 may be involved on the immunopathogenesis of MS, maybe facilitating the MOG recognizing by the immune system. Although awaiting experimental evidences, the data presented here may expand the scope of the endogenous retroviruses involvement on MS pathogenesis.
RESUMO
A group of 208 human immunodeficiency virus (HIV)-infected women in Brazil were studied for the presence of human papillomavirus with the general SPF(10) PCR primer set. Virtually all (98%) women were found positive for human papillomavirus (HPV) DNA. Genotyping by the reverse hybridization line probe assay (HPV-LiPA) revealed a high prevalence of multiple genotypes (78.9% of the cases), with an average of 3.1 genotypes per patient (range, 1 to 10 genotypes). HPV 6 was the most prevalent genotype and was observed in 80 (39.2%) patients, followed by types 51 (31.9%), 11 (26.0%), 18 (24.0%), and 16 (22.5%). Of the genotypes detected, 40.9% were low-risk genotypes. Twenty-two (10.5%) patients showed normal (Pap I) cytology, 149 (71.6%) patients had inflammation (Pap II), and 28 patients (13.4%) had a Pap III score. The prevalence of high-risk genotypes increased with the cytological classification. There were no significant associations between the number of HPV genotypes detected and the cytological classification, HIV viral load, and CD4 count in these patients. In conclusion, the highly sensitive SPF(10) LiPA system shows that a very high proportion of HIV-infected women in Brazil are infected with HPV and often carry multiple HPV genotypes.
Assuntos
Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Papillomaviridae/classificação , Infecções por Papillomavirus/epidemiologia , Infecções Tumorais por Vírus/epidemiologia , Brasil/epidemiologia , DNA Viral/análise , Feminino , Genótipo , HIV-1/isolamento & purificação , HIV-1/fisiologia , Humanos , Papillomaviridae/genética , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/virologia , Reação em Cadeia da Polimerase , Prevalência , Infecções Tumorais por Vírus/virologia , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/virologiaRESUMO
HIV-infected women from S o Paulo city were enrolled in a cross-sectional study on Human Papillomavirus (HPV) and cervical intraepithelial neoplasia (CIN) prevalence and their association with laboratory markers of AIDS, namely HIV viral load and CD(4)(+) cell counts. A cervical specimen was collected and submitted to Hybrid Capture, a test for HPV viral load determination. HPV-DNA was detected in 173 of 265 women (64.5%). Twenty (7.5%) women were infected by one or more low-risk viruses, 89 (33%) by one or more high-risk viruses, and 64 (24%) harbored at least one HPV type from each risk group. Abnormal smears were observed in 19% of the patients, though there were no invasive carcinomas. Severely immunosuppressed patients (CD(4)/microL <100) were at the greatest risk of having a cytological abnormality and a high high-risk HPV viral load.
Assuntos
Infecções por HIV/complicações , Infecções por HIV/virologia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/virologia , Infecções Tumorais por Vírus/complicações , Neoplasias do Colo do Útero/complicações , Carga Viral , Adolescente , Adulto , Fatores Etários , Idoso , Brasil/epidemiologia , Contagem de Linfócito CD4 , DNA Viral/análise , Feminino , HIV/isolamento & purificação , Humanos , Pessoa de Meia-Idade , Neoplasias de Células Escamosas/complicações , Neoplasias de Células Escamosas/epidemiologia , Neoplasias de Células Escamosas/virologia , Papillomaviridae/genética , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Prevalência , Fatores de Risco , Infecções Tumorais por Vírus/epidemiologia , Infecções Tumorais por Vírus/virologia , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/virologia , Esfregaço VaginalRESUMO
HIV-infected women from S o Paulo city were enrolled in a cross-sectional study on Human Papillomavirus (HPV) and cervical intraepithelial neoplasia (CIN) prevalence and their association with laboratory markers of AIDS, namely HIV viral load and CD(4)(+) cell counts. A cervical specimen was collected and submitted to Hybrid Capture, a test for HPV viral load determination. HPV-DNA was detected in 173 of 265 women (64.5). Twenty (7.5) women were infected by one or more low-risk viruses, 89 (33) by one or more high-risk viruses, and 64 (24) harbored at least one HPV type from each risk group. Abnormal smears were observed in 19 of the patients, though there were no invasive carcinomas. Severely immunosuppressed patients (CD(4)/microL <100) were at the greatest risk of having a cytological abnormality and a high high-risk HPV viral load.