Chlorella-based production of extracellular vesicle-embedded small RNA for prophylactic or therapeutic applications

The present invention relates to a novel method for producing small RNA targeting pathogenic factors, essential genes and/or antibiotic resistance genes of animal pathogens. The method further comprises the production of small RNAs against host susceptibility factors, known that silence, inactivation or deletion thereof enhances resistance to targeted pathogens. More specifically, the present invention relates to the expression of an exogenous RNA interference (RNAi) precursor in a Chlorella (Chlorella) cell, which in turn expresses and releases an extracellular vesicle (EV) embedded antimicrobial small RNA. Importantly, the Chlorella EV protects the antimicrobial small RNA from ribonuclease mediated digestion. They are also rapidly and effectively internalized by human alveolar epithelial cells, highlighting their potential to deliver antibacterial small RNA and control respiratory tract infections in these cells. The invention can therefore be used for prevention or treatment to reduce various infectious di