First report of Leishmania RNA virus 1 in Leishmania (Viannia) braziliensis clinical isolates from Rio de Janeiro State - Brazil

Abstract

BACKGROUND Leishmania parasites carry a double-stranded RNA virus (Leishmania RNA virus -LRV) that has been divided in LRV1 and LRV2.OBJECTIVES Leishmania (Viannia) braziliensis clinical isolates were assessed in order to determine LRV presence.METHODS Two-round polymerase chain reaction (PCR and nested PCR) was performed to detect LRV1 or LRV2 in L. (V.) braziliensis clinical isolates (n = 12). FINDINGS LRV1 was detected in three clinical isolates which was phylogenetically related to other sequences reported from other American tegumentary leishmaniasis (ATL) endemic areas of Brazil. Patients infected with L. (V.) braziliensis LRVnegative showed only cutaneous lesions while LRV-positive reported different manifestations.MAIN CONCLUSION Data presented here show for the first time that LRV1 is circulating in L. (V.) braziliensis clinical isolates from Rio de Janeiro State in Brazil.

First report of putative Leishmania RNA virus 2 (LRV2) in Leishmania infantum strains from canine and human visceral leishmaniasis cases in the southeast of Brazil

“…(29,45) In southeastern Brazil, only a few cases of LRV1 have been documented, including biopsies of patients with cutaneous leishmaniasis in the municipality of Caratinga, Minas Gerais (46) and in Rio de Janeiro. (30,47) In our study, the Brazilian LRV2 isolates showed a high degree of similarity with LRV2 isolates from various parts of Asia. However, it is important to interpret this result with caution due to the relatively small size of the amplified fragment (~300 bp).…”

“… 29 , 45 In southeastern Brazil, only a few cases of LRV1 have been documented, including biopsies of patients with cutaneous leishmaniasis in the municipality of Caratinga, Minas Gerais 46 and in Rio de Janeiro. 30 , 47 …”

“…(25) In the New World, LRV1s are predominant in clinical isolates from Bolivia, Colombia, Ecuador, French Guiana, Peru, and Suriname, (12,26,27,28) while being rare in southeastern Brazil. (29,30) LRV2 has been detected in Central Asian and Middle Eastern countries, with a higher prevalence in L. major compared to other susceptible species. (11,(31)(32)(33)(34)(35) Interestingly, LRV2-positive strains have not yet been detected in the New World, despite the presence of certain Old-World species of the subgenus Leishmania, known to be virus-positive in Asia.…”

Clinical and immunological spectra of human cutaneous leishmaniasis in North Africa and French Guiana

“…L. guyanensis shows unique characteristics with a mixed immune response (Figures 5, 6), which warrants further investigation to uncover the mechanisms that regulate immune responses and control inflammation caused by this parasite. Recently, a proposed relationship between Leishmania RNA Virus (LRV) and the severity of leishmaniasis has been suggested, as various factors are linked to the pathogenicity of the disease (146). Zabala-Peñafiel and colleagues demonstrated that L. guyanensis metastatic strains had a higher rate of LRV1 positivity than nonmetastatic strains (147).…”