It needs to be highlighted that recent studies by the authors revealed the beneficial impact of cathelicidin on the development of lung fibrosis in the course of HP, which was associated with restoring the balance in quantity of immune cells (NK cells, macrophages, lymphocytes: Tc, Th, Treg, B), cytokine production (IFNγ, TNFα, TGFβ1, IL1β, IL4, IL5, IL10, IL12α, IL13), and synthesis of extracellular matrix components (hydroxyproline, collagens) [44]. The gene discussed is TGFB1; the disease is pulmonary fibrosis.