CD27 and infection: At month 6 post-infection (pre-vaccination), 80% of those 30 clones had a CD21+ resting Bm cell phenotype (Fig. 6b), whereas at month 12 post-infection (post-vaccination) 32% of persistent Bm clones showed a CD21–CD27+CD71+ and 28% a CD21–CD27–FcRL5+ Bm cell phenotype.