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What is CD 4 are associated with - and explain in detail?
T cells can differentiate into effector cells. Helper (CD4) T-cell activity, in addition to stimulating B cells to produce antibodies, promotes the development of delayed hypersensitivity and thereby also serves in the defense against intracellular agents, including intracellular bacteria (eg, mycobacteria), fungi, protozoa, and viruses. Reff: Ananthanarayanan & Panikers textbook of microbiology 9th edition pg: 135