Preparation of a Non-Cardiomyocyte Cell Suspension for Single-Cell RNA Sequencing from a Post-Myocardial Infarction Adult Mouse Heart.

Myocardial infarction (MI) is one of the most common cardiovascular diseases, with increasing mortality worldwide. Non-cardiomyocytes account for more than half of the total cardiac cell population, and they contribute to adaptive compensations upon myocardial injury, including inflammatory responses, tissue repair, and scar formation. To study the post-MI cardiac microenvironment, single-cell RNA sequencing (scRNA-seq) is widely used to identify different cardiac cell types and intercellular communications. Among the procedures of scRNA-seq sample preparation, preparing the cell suspension is one of the most critical steps, because the cell viability can affect the quality of the scRNA-seq results. Therefore, we designed an experimental protocol for preparing a non-cardiomyocyte cell suspension from post-MI mouse hearts with an extra focus on improving the cell viability by choosing mild digestive enzymes, controlling the digestion time, and applying fluorescence-activated cell sorting (FACS). Finally, we isolated CD45+ cells from the non-cardiomyocyte cell suspension obtained through this protocol, and then we performed scRNA-seq.

Molecular Targets for Antibody-Based Anti-Biofilm Therapy in Infective Endocarditis.

Infective endocarditis (IE) is a heart disease caused by the infection of heart valves, majorly caused by Staphilococcus aureus. IE is initiated by bacteria entering the blood circulation in favouring conditions (e.g., during invasive procedures). So far, the conventional antimicrobial strategies based on the usage of antibiotics remain the major intervention for treating IE. Nevertheless, the therapeutic efficacy of antibiotics in IE is limited not only by the bacterial drug resistance, but also by the formation of biofilms, which resist the penetration of antibiotics into bacterial cells. To overcome these drawbacks, the development of anti-biofilm treatments that can expose bacteria and make them more susceptible to the action of antibiotics, therefore resulting in reduced antimicrobial resistance, is urgently required. A series of anti-biofilm strategies have been developed, and this review will focus in particular on the development of anti-biofilm antibodies. Based on the results previously reported in the literature, several potential anti-biofilm targets are discussed, such as bacterial adhesins, biofilm matrix and bacterial toxins, covering their antigenic properties (with the identification of potential promising epitopes), functional mechanisms, as well as the antibodies already developed against these targets and, where feasible, their clinical translation.