Evaluation of heterologous monoclonal antibodies for intracellular cytokine detection in Cavia porcellus during experimental Leishmania enriettii infection

Introduction The rodent Cavia porcellus (Cavidae) is a common model to study several diseases, including cutaneous leishmaniasis (CL). This rodent is specifically infected by Leishmania ( Mundinia ) enriettii , causing nodular and ulcerated skin lesions, and has the potential to visceralize. In the past decades, interest during the immunopathological events underlying the interaction Leishmania -host has emerged in this model. The scarcity of specific antibodies for immunophenotyping and cytokines has made the study of L. enriettii infection difficult. Using cross-reactivity approaches, we aimed to understand the immunopathological events during infection. Methods Animals were infected in the nose using the reference strain of L. enriettii (L88) plus salivary gland extracts (SGE) of Lutzomyia longipalpis . They were followed for 11 weeks until lesion healing. Skin biopsies and blood were recovered after the 5th and 11th weeks post-infection (PI). Results and discussion During our standardization procedures, we failed to detect leukocytes from skin lesions. In the blood, after selecting lymphocytes for size and granularity, we detected cytokines (IL-4, IL-6, IL-8, IL-10, IFN-γ, TNF-α, and TGF-β) using human, mouse, and bovine antibodies. This phenomenon was confirmed after bioinformatic analysis that detected considerable levels of similarity and identity among those hosts with C. porcellus . In conclusion, cross-reactivity occurred for cytokines. On the other hand, it did not work for the five cell surface markers tested. We recommend expanding the cell surface antibodies and the use of other methods for the skin.