APOD and COVID-19: Also, according to IPA analysis, some of them have been associated with viral infection (APOD, APOH, SERPINA1), severe COVID-19 (APOD, APOH, PCYOX1), or leukocyte migration (APOD, IGHV3-13, IGHV3-23, SERPINA1, IGLC7, IGLV3-21).