PMBC immune cell composition
PD, CR/PR/SD
Baseline and on-treatment characteristics of peripheral blood immune cell composition were analyzed in response to therapy. Two high parameter (> 28) spectral cytometry panels were designed to identify both broad immune subsets and detailed T cell subsets. At baseline, we found no association of response and frequencies of CD3 + T cells, natural killer (NK) cells, natural killer T cells (NKT), γδ T cells, or B cells within total CD45 + leukocytes (Supplemental Fig. 1A). Intriguingly, the patient with PD had the highest fraction (11.0% PD vs. 6.3% mean CR/PR/SD) of terminally differentiated NK cells (CD56dim CD16 +) among all NK cells at baseline (Supplemental Fig. 1B). Moreover, the patient with PD also demonstrated fewer naïve B cells (48.4% in PD vs. 75.8% mean in CR/PR/SD and higher levels of plasmablasts (15.2% in PD vs. 1.5% mean in CR/PR/SD) among all B cells compared to other patients (Supplemental Fig. 1C). No differences in the subset composition of monocytes (classical, ClMono; intermediate, IntMono; non-classical, NcMono) or dendritic cells (conventional type 1, cDC1; conventional type 2, cDC2; plasmacytoid, pDC) were observed (Supplemental Fig. 1D and E). We then examined how these major immune populations changed during treatment. From pre-treatment to C2D1, the fraction of CD3 + T cells among total CD45 + cells increased significantly (