An abnormal proportion of effector memory CD4+ T cells compared to the total number of T cells in the blood. These are memory cells that are short-lived cells that migrate to the site of an infection and attempt to eliminate the pathogen. These cells have the phenotype CD3-positive, CD4-positive, CD62L-negative, CCR7-negative, CD127-positive, CD45RA-negative, CD45RO-positive, and CD25-negative. [from
HPO]