Phylogenetic and Similarity Analysis of HTLV-1 Isolates from HIV-Coinfected Patients from the South and Southeast Regions of Brazil

Abstract

BackgroundHTLV-1 is endemic in Brazil (0.07-15.9%) and HIV/ HTLV-1-coinfection has been detected, mostly in the North and Northeast regions. This study characterized HTLV-1 isolates from HIV-coinfected patients from Southern and Southeastern Brazil. Material and methodsDNA from 17 HIV/HTLV-1-co-infected patients; 5 from the South and 12 from Southeast were amplified by nested-PCR (env and LTR) and sequenced. HTLV subtyping was performed by NCBI-Genotyping and REGASubtyping tools websites and by phylogenetic methods using Paup4 and MEGA4. ResultsEnv sequences (705-bp) from 15 isolates and LTR sequences (731-bp) from 17 isolates were obtained. Molecular analysis of env and LTR sequences disclosed respectively, nucleotide similarities of 99.5% and 98.8% within sequences, 99% and 97.4% with ATK, and 91.6% and 90.3% with Mel5. Four sequences that showed the highest similarities with ATK clustered separately in the trees (p≤0.001 for env and LTR, bootstrap=96% for LTR); they had C386T and T594C nucleotide substitutions in LTR sequences. All except these four sequences had mutations T5637G, T5730C, A6120G in env and T500A, A549G, G676A, T766C, T767G in LTR sequences. Six sequences presented the amino acid change V1981I and clustered together in the env tree.All isolates belonged to Cosmopolitan HTLV-1a subtype. ConclusionsThese data show that Cosmopolitan HTLV-1a subtype is also frequent in HIV-coinfected patients from Southern and Southeastern Brazil, suggesting spreading of HTLV-1 in the country. The mutations observed should be monitored in the context of molecular epidemiology.

Human T-lymphotropic virus 1aA circulation and risk factors for sexually transmitted infections in an Amazon geographic area with lowest human development index (Marajó Island, Northern Brazil)

“…HTLV-1aA is the major circulating viral subtype in Brazil, and the states of Bahia [40], São Paulo [41] and Pará [42] have the highest prevalence rates of infection. Analyses conducted in HTLV-1 carriers in Brazil, both symptomatic (TSP/HAM) and asymptomatic, indicated that the prevalence of HTLV-1aA was greater than that of other viral subtypes and subgroups [43].…”

Tax Gene Characterization of Human T-Lymphotropic Virus Type 1 Strains from Brazilian HIV-Coinfected Patients

“…[14][15][16] To gain further insight into the history of HTLV-1 in Brazil, especially in the at-risk population infected by HIV-1 in the south and southeast regions, we conducted the present and preliminary studies. A few years ago, we determined the prevalence of HTLV-1 and HTLV-2 in patients with HIV/ AIDS from Londrina and its vicinities in the south of Brazil and detected HIV/HTLV-1/2 coinfection in 6.4% of cases 16 ; subsequently, we characterized HTLV-1 isolates from southern and southeastern Brazil using the LTR and env regions 17 and confirmed the HTLV-1a Cosmopolitan subtype, subgroup A, which clustered into two Latin American clusters.…”

“…The study population consisted of 13 patients with HIV/AIDS who were coinfected with HTLV-1 from Londrina and its vicinities (BRLO) and Sã o Paulo (BRSP). 17 Five patients are from Londrina (five men) and eight are from Sã o Paulo (five women and three men). DNA samples were extracted from peripheral blood leukocytes, and the tax region was amplified using a previously described modified protocol, 11 in which PCR was optimized using the GoTaq Colorless Master Mix (Promega Corporation, Madison, WI) to improve stability.…”

“…Of note, the previous molecular analysis of the LTR and env regions of such isolates characterized these strains as belonging to the HTLV-1a Cosmopolitan subtype, transcontinental subgroup A, clustering into two branches of Latin America, 17 the same branches detected in the present study Phylogenetic tree constructed by the neighborjoining method using the PAUP v4b10 software for the partial tax region of 977 bp (position 7378-8354 relative to the ATK prototype) of human T-lymphotropic virus type 1 (HTLV-1) of 49 isolates, including sequences from the south and southeast regions of Brazil (GenBank AN JN887698-JN887710) in bold, generated with the TrN + G model. Bootstrap values above 65% and zero length using the likelihood ratio test with p < 0.001 (**) and p £ 0.05 (*) in key branches are depicted.…”

Inability to Detect Human T Cell Lymphotropic Virus Type 2-Specific Antibodies in a Patient Coinfected with HIV-1, Human T Cell Lymphotropic Virus Type 1, Human T Cell Lymphotropic Virus Type 2, and Hepatitis C Virus

“…In October 2012, using PCR protocols optimized for Brazilian isolates, [13][14][15] we retested the patient's blood sample from 2002 and compared it with a new blood sample from 2012; both samples were positive by PCR for HTLV-1 and …”