FIGURE 1.

Humoral and cell‐mediated immune response to BNT162b2 vaccine in a CLL patient A, The characterization of peripheral blood mononuclear cells (PBMC) performed by flow cytometry shows the frequency and phenotype of B (CD19+) and T (CD3+) cells from the subject with CLL. B cells expressing IgK and CD5 represent the large majority of circulating PBMC, confirming a diagnosis of CLL. The frequency of T cells was low but CD4/CD8 T cell ratio was in the normal range. B,C, A significant increase in anti‐RBD IgG and in the neutralization titres was observed 2 weeks after boost (T2), although at lower level than HCWs. VNT (viral neutralization titre).D, Spike‐specific T cell response was detected before the boost (T1) and strongly increased at T2, reaching level similar to HCW. Data from HCWs (n = 10) are shown as boxer and whiskers plot (median, 25th and 75th percentile)