These include: lymphopenia; neutrophilia; neutrophil activation; increased intermediate and non-classical monocytes; high CD64 expression on monocytes and neutrophils; and raised levels of IL-6, IL-18, PAI-1, sCD25, sTNF-R, IP-10, MPO, and PTX3 (Takeshita et al., 1999; Senzaki et al., 2003; Weng et al., 2013; Ko et al., 2015; Hokibara et al., 2016; Ching et al., 2020). The gene discussed is MPO; the disease is lymphopenia.