Evaluation of the therapeutic effect of human miRNAs on the infection of human small airway pulmonary tissue by planktonic and biofilm-derived Histoplasma capsulatum yeasts

• Grant number: 25/00194-7
• Support Opportunities: Scholarships in Brazil - Master
• Start date: November 01, 2025
• End date: October 31, 2027
• Field of knowledge: Health Sciences - Pharmacy
• Principal Investigator: Ana Marisa Fusco Almeida
• Grantee: Luana Apolinário de Lima
• Host Institution: Faculdade de Ciências Farmacêuticas (FCFAR). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Associated research grant: 25/04125-0 - Integrative Multi-Omics Investigation of the Pathogen-Host Interaction in Three-Dimensional Human Lung Tissue Models for biofilm infection of Histoplasma capsulatum and Cryptococcus neoformans, AP.R

Abstract

Histoplasmosis is an invasive fungal infection (IFI) of great global importance caused by the dimorphic fungus Histoplasma capsulatum. According to the World Health Organization, in the Americas, histoplasmosis causes more deaths among individuals with HIV/AIDS than tuberculosis, with 500,000 new cases annually. Moreover, in endemic areas, the incidence of histoplasmosis in individuals with HIV/AIDS ranges from 2% to 25%, with 60% of these cases resulting in death. One of the reasons for the high lethality of histoplasmosis in certain populations is the limited availability of drugs to treat it (itraconazole and amphotericin B), which are associated with severe liver and kidney toxicity due to the prolonged administration required. Another issue with the existing therapy is the formation of biofilms, which makes the infection even more resistant to available medications. Recently, during the COVID-19 pandemic, one of the treatments for the disease involved the use of dexamethasone, a drug that promotes immunosuppression, leading to an increased frequency of IFIs associated with COVID-19 in patients in intensive care units (ICU). In this context, gene therapies based on antagomirs emerge as a promising approach for the treatment of infectious diseases, as they consist of small synthetic oligonucleotides designed to inhibit specific microRNAs (miRNAs). These are non-coding RNA molecules that regulate gene expression post-transcriptionally and play critical roles in the host's response to infections. Thus, this master's project aims to evaluate the therapeutic potential of human miRNAs during the infection of human small airway pulmonary tissue (developed under the FAPESP Regular Grant Process 2022/15826-0) by Histoplasma sp.planktonic yeasts and biofilm-derived cells. To achieve this, the miRNAs hsa-miR-23a-3p, hsa-miR-374a-5p, hsa-miR-128-3p, hsa-miR-15b-5p, and hsa-miR-651-6p, previously identified by our group (FAPESP Regular Grant Process 2016/11836-0), will first be quantified via RT-qPCR during pulmonary tissue infections. The protective potential of these miRNAs will then be assessed using anti-miRNAs in human lung tissue composed of MRC-5, THP-1, and Calu-3 cells transfected with pTagBFP-Akt1 plasmids to evaluate the signaling of the protein kinase beta-alpha pathway, which is related to survival, cell growth, and metabolism. This analysis will employ Multiparametric Multifocal Microscopy (MMM) and Transmission Electron Microscopy (TEM). Through these methodologies, the project expects to obtain results related to actin cytoskeleton binding processes, extracellular matrix activity, hypoxia, and the reduction of vascular permeability in lung tissue. Additionally, it will assess T-cell signaling, TNF-¿ downregulation, and the regulation of apoptosis in human lung tissue treated with specific antagomirs, thereby advancing knowledge on gene therapy applied to infectious diseases. (AU)