In vitro characterization of Leishmania (Viannia) braziliensis isolates from patients with different responses to Glucantime® treatment from Northwest Paraná, Brazil

Abstract

Leishmaniasis is a group of diseases that presents various clinical manifestations. Many studies have shown that the parasite plays an important role in the clinical manifestations and prognosis of this disease. The cutaneous and mucosal forms of American tegumentary leishmaniasis (ATL) are associated with Leishmania (Viannia) braziliensis, which exhibits intraspecific genetic polymorphisms and various clinical manifestations. The present study focused on four different L. braziliensis strains that were isolated from patients with distinct Glucantime(®) treatment responses. The isolates were described based on their molecular, biological, and infective characteristics. Growth patterns in culture medium and different grow phases were analyzed, MID-Logarithimic (Mid-LOG), Logarithimic (LOG) and Stationary (STAT) phases. Complement resistance was evaluated using guinea pig serum. Infection to murine peritoneal macrophages, cytokine and nitric oxide were analyzed. Ultrastructural features were determined by transmission electron microscopy, and molecular characteristics were determined based on random amplified polymorphic DNA (RAPD). All of the L. braziliensis isolates showed typical growth and similar complement sensitivity patterns. Markedly lower infectivity indexes were observed for all strains in the LOG phase, with different cytokine profiles. The ultrastructure analysis revealed distinct differences between the MID-LOG, LOG, and STAT phases. The RAPD results showed a divergence between the isolates of the L. braziliensis. The in vitro characterization of L. braziliensis isolates from humans with different treatment responses using various parameters enabled us to observe differences among the isolates. Molecular and in vivo characterizations are currently under study to improve understanding of the parasite-host interaction that can imply in the clinical manifestation differences.

Risk factors for antimony treatment failure in American Cutaneous Leishmaniasis in Northwestern-Argentina

“…[26] identified two different genotypes of L. braziliensis (Ab1 and Ab2), and one of them (Ab2) was only found in the zone of the Zenta valley (Yungas Ecoregion), which is where we found most cases of TF. Studies from Brazil reported intraspecific differences (eg genetic, ultrastructural) in isolates from patients with different responses to treatment [27,28].…”

A New Target Organ of Leishmania (Viannia) braziliensis Chronic Infection: The Intestine

“…This includes decreasing NO production (Vodovotz et al, 1993;Bogdan, 2020), which is one of the principal defense mechanisms against infection (Bogdan, 2020). In vitro studies using the same strains as our study have not detected NO production by macrophages (Fernandes et al, 2016).…”

“…For example, in BALB/c and C57BL/6 mice, different profiles of inflammatory infiltrates in livers and spleens were found with or without the presence of parasite (Pereira et al, 2009). Fernandes et al (2016) demonstrated various cytokine expressions and macrophageinfectivity rates in in vitro experiments with the same strains used in our study.…”

“…The MHOM/ BR/2000/1655 (1655) strain was isolated from a patient whose infection was considered resistant by reactivation of the previously-healed lesion. These isolates were cultured, cryopreserved, and identified by the Oswaldo Cruz Institute, Rio de Janeiro, Brazil (Fernandes et al, 2016).…”

“…The diversity of clinical forms of leishmaniasis caused by L. (V.) braziliensis and disease severity are related to the immune system (Fernandes et al, 2016), genetic factors, the clinical condition of the host (Quaresma et al, 2018), and the inoculum (Ribeiro-Romão et al, 2014) and strain of the parasite (Vieira et al, 2019); this species presents high levels of genetic polymorphism (Patino et al, 2020). Different strains found in the same region can cause different clinical forms (Guimarães et al, 2016;Quaresma et al, 2018;Rugani et al, 2018) and therapeutic responses (Fernandes et al, 2016;Gagini et al, 2017), even in the same patient (Hoyos et al, 2019). Lesions are destructive and principally affect the skin and mucus membranes in the oral, nasal, and oropharyngeal tracts (Ministeŕio da Saúde, 2017;Conceicão-Silva and Morgado, 2019).…”