CD28 and myalgic encephalomeyelitis/chronic fatigue syndrome: There were also small changes in other minor CD8+ T cell populations, with small reductions in proportions of CCR7-CD45RA+CD28+CD57+, CCR7+CD45RA-CD28+CD57-, and CCR7-CD45RA-CD28+CD57- cells in people with ME/CFS and an increased proportion of CCR7+CD45RA+CD28-CD57- cells.