**Abstract**

Human β-defensin-2 is a small cationic peptide that is part of the innate and adaptive immunity. It is expressed mainly in the epithelium and has a broad spectrum of antimicrobial activity against bacteria, fungi and viruses. In addition to its antimicrobial activity, it has other biological functions. The alteration of the expression of β-defensin-2 in the respiratory epithelium has been associated with the pathogenesis of several respiratory diseases such as asthma, pulmonary fibrosis, pneumonia, tuberculosis, rhinitis, etc. The acute respiratory infections caused by viruses are the main cause of morbidity and mortality in the world; there are few studies and it is necessary to study this peptide to understand its role in the viral pathogenesis. In addition, it also becomes relevant in its potential to take advantage of its properties in the development of alternative therapies that allow the prevention or treatment of viral respiratory infections.

**Keywords:** β-defensin-2, pathogenesis, respiratory diseases, viral infections
