Differential Gene Expression and Infection Profiles of Cutaneous and Mucosal Leishmania braziliensis Isolates from the Same Patient

Abstract

BackgroundLeishmaniasis is a complex disease in which clinical outcome depends on factors such as parasite species, host genetics and immunity and vector species. In Brazil, Leishmania (Viannia) braziliensis is a major etiological agent of cutaneous (CL) and mucosal leishmaniasis (MCL), a disfiguring form of the disease, which occurs in ~10% of L. braziliensis-infected patients. Thus, clinical isolates from patients with CL and MCL may be a relevant source of information to uncover parasite factors contributing to pathogenesis. In this study, we investigated two pairs of L. (V.) braziliensis isolates from mucosal (LbrM) and cutaneous (LbrC) sites of the same patient to identify factors distinguishing parasites that migrate from those that remain at the primary site of infection.Methodology/Principal FindingsWe observed no major genomic divergences among the clinical isolates by molecular karyotype and genomic sequencing. RT-PCR revealed that the isolates lacked Leishmania RNA virus (LRV). However, the isolates exhibited distinct in vivo pathogenesis in BALB/c mice; the LbrC isolates were more virulent than the LbrM isolates. Metabolomic analysis revealed significantly increased levels of 14 metabolites in LbrC parasites and 31 metabolites in LbrM parasites that were mainly related to inflammation and chemotaxis. A proteome comparative analysis revealed the overexpression of LbrPGF2S (prostaglandin f2-alpha synthase) and HSP70 in both LbrC isolates. Overexpression of LbrPGF2S in LbrC and LbrM promastigotes led to an increase in infected macrophages and the number of amastigotes per cell at 24–48 h post-infection (p.i.).Conclusions/SignificanceDespite sharing high similarity at the genome structure and ploidy levels, the parasites exhibited divergent expressed genomes. The proteome and metabolome results indicated differential profiles between the cutaneous and mucosal isolates, primarily related to inflammation and chemotaxis. BALB/c infection revealed that the cutaneous isolates were more virulent than the mucosal parasites. Furthermore, our data suggest that the LbrPGF2S protein is a candidate to contribute to parasite virulence profiles in the mammalian host.

Proteomics and Leishmaniasis: Potential Clinical Applications

“…Proteomic data indicated that prostaglandin F2 α synthase and a putative HSP70 were more abundant in LCL parasites from both patients. These parasites were more virulent in BALB/c mice, and overexpression of prostaglandin F2 α synthase led to an increase in macrophage infection in vitro, as previously observed for L. infantum …”

“…Until today, there is no proteomic analysis of L. braziliensis from DL. Besides, only one paper has compared proteomes of LCL and ML . In this work, genome, metabolome and proteome of two pairs of parasites isolated from cutaneous and mucosal lesions from the same patient were compared.…”

Sclerosing Orbital Inflammation Caused by Leishmania braziliensis

“…Since Leishmania is an intracellular parasite in the mammalian host, it has been postulated that migration occurs through infected macrophages, although the mechanisms involved in the preferential location of the disease on the nasal mucosa are not known. 8 We believe that histiocytes or other inflammatory cells targeted by the parasite migrated by proximity to the medial orbital wall and participated and probably contributed to the same granulomatous reaction seen in the oral and nasal mucosae. Since these lesions have a typically low parasite load, it is not surprising that the amastigote forms of the parasite could not be visualized.…”

Toward an objective diagnostic for detection of Leishmania RNA virus (LRV) in clinical samples from cutaneous leishmaniasis patients

“…An explanation for the biological events responsible for this loss was not addressed in the present study. However, it is important to note that if this viral loss commonly occurs among other Leishmania strains, previous studies using LRV detection exclusively in isolates may have underestimated the rate of viral co-infection for at least some Leishmania species (17, 19–21, 25, 29–32).…”