Authors did not elucidate the cause of NLRP3 inflammasome activation by COVID-19 exosomes; however, it has been noted in conditions, such as diabetic retinopathy, that exosomes may carry damage-associated molecular patterns, such as high mobility group box-1 (HMGB-1)[68-70], and induce the NLRP3 inflammasome via the canonical pathway[71]. Here, HMGB1 is linked to diabetic retinopathy.