CD19 and chronic obstructive pulmonary disease: We assessed the levels of CD3+, CD4+, CD8+, CD4+/CD8+, CD19+, CD25+, HLA-DR, total IgE, TNF-α, IL-4, IFN-γ, TXB2, and LTB4 in patients with comorbid COPD and asthma. Results.