Lymphocytes are normal components of the immune system. Total T cells (CD3+), T-helper cells (CD4+), cytotoxic T-cells (CD8+), B cells (CD19+), and natural killer cells (CD16+/56+) cells were measured using a flow cytometric assay. Normal absolute counts in adults are as follows: CD3+ (983-3572 cells/μl), CD4+ (491-2000 cells/μ), CD8+ (314-2087 cells/μ), CD19+ (64-800 cells/μ), CD16/56+ (27-693 cells/μ).41 (link) The assay used Becton Dickinson Trucount™ beads and FACSCanto software to determine absolute counts of the lymphocyte subsets.
Cytokines are important in cell signaling and produced by a wide variety of lymphocytes, although diagnostic reference ranges for these assays have yet to be established and validated in adults.42 (link) Plasma concentrations of pro-inflammatory cytokines, including interleukin (IL)-1, IL-6, IL-8, and TNF-α, were measured using a sandwich immunoassay (V-Plex MSD Muli-spot system, Meso Scale Discovery, Rockville, MD) according to manufacturer's instructions. Pro-inflammatory cytokine samples were run in triplicate.