Provided are methods for the treatment of disease and promotion of healing that include providing a therapeutically effective amount of a mammalian antimicrobial peptide (AMP) or analog thereof, in particular a cathelicidin or cathelicidin fragment or cathelicidin analog, thereby treating the disease in the subject in need thereof. Also provided are specific analogs or fragments of cathelicidin that function as agonists, as do endogenous cathelicidins, or as either dominant negatives or as inhibitors to endogenous cathelicidin or to other endogenous AMPs or that compete with pro-inflammatory agents or fragments of AMPs on cognate receptors without inducing disease.