High-through identification of T cell-specific phage-exposed mimotopes using PBMCs from tegumentary leishmaniasis patients and their use as vaccine candidates against Leishmania amazonensis infection

Abstract

In the current study, phage-exposed mimotopes as targets against tegumentary leishmaniasis (TL) were selected by means of bio-panning cycles employing sera of TL patients and healthy subjects, besides the immune stimulation of peripheral blood mononuclear cells (PBMCs) collected from untreated and treated TL patients and healthy subjects. The clones were evaluated regarding their specific interferon-γ (IFN-γ) and interleukin-4 (IL-4) production in the in vitro cultures, and selectivity and specificity values were calculated, and those presenting the best results were selected for the in vivo experiments. Two clones, namely A4 and A8, were identified and used in immunization protocols from BALB/c mice to protect against Leishmania amazonensis infection. Results showed a polarized Th1 response generated after vaccination, being based on significantly higher levels of IFN-γ, IL-2, IL-12, tumour necrosis factor-α (TNF-α) and granulocyte-macrophage colony-stimulating factor (GM-CSF); which were associated with lower production of specific IL-4, IL-10 and immunoglobulin G1 (IgG1) antibodies. Vaccinated mice presented significant reductions in the parasite load in the infected tissue and distinct organs, when compared with controls. In conclusion, we presented a strategy to identify new mimotopes able to induce Th1 response in PBMCs from TL patients and healthy subjects, and that were successfully used to protect against L. amazonensis infection.

Identification of male infertility-related long non-coding RNAs and their functions based on a competing endogenous RNA network

“…High-throughput technology has been extensively used to investigate gene expression in male infertility, providing a novel method to identify important genes and explore the disease. 7 , 8 Long non-coding (lnc)RNAs are a type of non-coding RNA, exceeding 200 nucleotides in length, which lack coding ability and are an important part of all non-coding transcripts. 9 , 10 LncRNAs regulate the translation of genes by binding micro (mi)RNAs, 11 , 12 but although miRNAs have attracted extensive attention for their role in a variety of physiological and pathophysiological processes, the role of lncRNAs has not been fully elucidated.…”

Identification of the hub genes and transcription factor‑miRNA axes involved in Helicobacter pylori‑associated gastric cancer

“…Therefore, identification of the mechanisms of HP-associated gastric cancer is required to prevent progression and improve survival times. In recent years, high-throughput technology has been widely utilized to investigate gene expression levels in various types of tumor, such as colorectal ( 32 ) and ovarian cancer ( 33 ), providing a novel method to identify significant genes and determine their effects on tumor progression and initiation ( 34 , 35 ).…”

Diagnostic application of sensitive and specific phage-exposed epitopes for visceral leishmaniasis and human immunodeficiency virus coinfection

“…Phage display is an in vitro selection strategy in which a peptide, protein or antibody is fused to a coat protein of phage capsid, which is displayed together with a fusion protein on the exogenous surface of the capsid (Alfaleh et al, 2020). This technique has been applied to identify novel vaccine candidates and/or diagnostic targets against a variety of diseases, such as leishmaniasis (Costa et al, 2014;Toledo-Machado et al, 2015a, 2015bCarvalho et al, 2019). In this context, in the current study, the phage display technology applying a subtractive selection strategy was performed, aiming to identify new diagnostic targets for VL and VL/HIV coinfection.…”