In tuberculosis (TB), it has not been elucidated if the frequency and quality of polyfunctional CD4+ T-cell responses elicited in mice by different types of vaccines correlate with protective immunity (14–17), while human studies have shown that a consistent response of CD4+ T cells coexpressing IFN-γ, TNF-α, and IL-2 was associated with acute TB infection (18). This evidence concerns the gene CD4 and tuberculosis.