level of serine/threonine-protein phosphatase 2A 65 kDa regulatory subunit A alpha isoform in blood serum (OBA_2043007) is the amount of a serine/threonine-protein phosphatase 2A 65 kDa regulatory subunit A alpha isoform when measured in blood serum. Also known as: blood serum serine/threonine-protein phosphatase 2A 65 kDa regulatory subunit A alpha isoform amount.