Cellular immune response evaluation of cutaneous leishmaniasis patients cells stimulated with Leishmania (Viannia) braziliensis antigenic fractions before and after clinical cure

Abstract

American cutaneous leishmaniasis (ACL) is a disease where susceptibility or resistance is dependent on T cell response. This is characterized by an increased in CD4⁺ T cells, capable of inducing opposite disease profiles, and CD8⁺ T cells, that are related to immuno protection. We characterized T lymphocytes from patients before and after treatment, patients that spontaneously healed and controls, also evaluating their production of IL-10, IL-4, TNF-α and IFN-γ, after stimulation with soluble/insoluble antigenic fractions of Leishmania (Viannia) braziliensis. We observed the production of suppressive cytokines in the early phase of leishmaniasis with significant presence CD4⁺ T cells, suggesting their connection with disease progression. After healing, the immune pattern observed was a type 1 response, what seems to be associated with cure and/or protection in the ACL. The results also showed that both fractions induced a specific immune response, contributing to the search for relevant antigens in this disease.

American tegumentary leishmaniasis: mRNA expression for Th1 and Treg mediators are predominant in patients with recent active disease

“…Similarly, high IFN-γ secreted levels were verified using capture ELISA in recent active disease (Assis Souza and others, 2012; De Assis Souza and others, 2013), and its mRNA was also expressed in biopsy samples of active LCL lesions (Cáceres-Dittmar and others, 1993). In contrast, our group previously observed by flow cytometry low IFN-γ levels and a predominance of IL-10 and IL-4 after 48h of PBMC incubation during the first 60 days of active disease (Brelaz and others, 2012). The different period of PBMC incubation in the present study (24h) may contribute to obtain different results.…”

“…We previously observed significant production of TNF-α in PBMC supernatants from patients with recent disease using capture ELISA (Assis Souza and others, 2012; De Assis Souza and others, 2013). Also according to these previous works, this cytokine seems to contribute to the achievement of clinical cure after chemotherapy, and it was also suggested by Brelaz and others (2012). Conversely, the involvement of TNF-α in longer-lasting lesions was also documented (Bacellar and others, 2009), what suggests that the different levels of TNF-α observed here and in other studies may exist due to the genetic constitution of the host.…”

“…Here, we observed an up-regulation of IL-4 transcripts in patients in response to AgIns, but even so, they appeared to express a predominant Th1 profile at the moment of the evaluation. In contrast, IL-4 secretion was shown to be dominant in the first 60 days of lesion existence (Brelaz-de-Castro and others, 2012;Brelaz and others, 2012;Maurer and others, 2009). It seems that, at the moment of the evaluation, lower mRNA levels were detected due to the rapid processing of this material, including its translation into actual IL-4 cytokine.…”

“…Thus, this response has been evaluated by our group in the presence of antigenic fractions of L (V.) braziliensis by cytokine and NO measurement and cell immunophenotyping in patients with different clinical status (Assis Souza and others, 2012;De Assis Souza and others, 2013;Brelaz de Castro and others, 2012). However, gene expression analysis by quantitative polymerase chain reaction concerning the immunological mediators involved in human ATL is not frequently performed, and even less regarding Th17 and Treg components.…”

Field Validation of SYBR Green- and TaqMan-Based Real-Time PCR Using Biopsy and Swab Samples To Diagnose American Tegumentary Leishmaniasis in an Area Where Leishmania (Viannia) braziliensis Is Endemic

“…A noninvasive, extremely sensitive, and highly specific exam is essential, particularly for ML, in which a low parasite quantity is expected (17,18). In the current study, SYBR Green and TaqMan were 100% specific.…”