HMGB1 and keratitis: Unfortunately, many of those approaches have drawbacks that limit their use in a clinical setting.38 Case in point, recently, this laboratory demonstrated the use of a small interfering RNA (siHMGB1) to knock down HMGB1 in a mouse model of P. aeruginosa keratitis.15 Treatment with siHMGB1 led to improved disease outcomes along with reduction in proinflammatory cytokines, an increase in anti-inflammatory cytokines and reduced neutrophil infiltration.