CD38 and pertussis: NK cell cluster 1 (CD56loCD16lo Perforin+CD38+CD45RA+FcεRIγ+) and cluster 3 (CD56-CD16+ FcεRIγ+) measured at birth and week 4 were consistently associated with responders to pertussis vaccine at week 15, while cluster 8 (CD56+CD16+Perforin+CD38+CD45RA+DNAM1+2B4+Nkp30+NKp46+NKG2A+Siglec-7+FcεRIγ+) was associated with non-responders to pertussis vaccine (Fig. 5B).