Two studies have assessed the expression of TNFR1 versus TNFR2 on immune cells (121, 123), compared to healthy controls: patients with atopic dermatitis have increased expression of TFNR1 on their T-cells (121); patients with hypersensitivity pneumonitis have elevated TNFR1 expression on alveolar macrophages but elevated TNFR2 on peripheral lymphocytes (123). The gene discussed is TNFRSF1A; the disease is hypersensitivity pneumonitis.