CD4 and Parkinson disease: Compared to control samples, PD patients have more granulocytes (p=1.0×10–9 in Caucasians, p=0.00066 in Hispanics Figure 4O,P) and plasma cells (activated B cells) (p=0.00065 in Caucasians Figure 4S) but fewer helper (CD4+) T cells (p=1.4×10–6 in Caucasians, p=0.0024 in Hispanics, Figure 4G,H), fewer naïve CD4+ T cells (p=0.0074 in Caucasians, p=0.13 in Hispanics Figure 4I,J), fewer B cells (p=1.6×10–5 in Caucasians, p=4.5×10–5 in Hispanics Figure 4Q,R), and fewer cytotoxic (CD8+) T cells (p=0.0017 in Caucasians, p=0.072 in Hispanics Figure 4A,B).