Table 2.

Properties of lymphocytes

Cells	Receptors	CD marker	Type	Role	Secreted products
B	IgM, IgD	−	−	Cells are activated via these receptors	−
T	α,β or γ,δ	CD4	Th‐2	Helps B cells make antibodies and   certain cytokines	IgM, IgG, IgA, IgE Mainly IL −4, −5, −6, −10
	α,β or γ,δ		Th‐1	Helps B cells make antibodies and   certain cytokines	Some subclasses of IgG IL −2, IFNγ, TNFα, β
	α,β or γ,δ		Th‐1	Helps differentiation of CD8+ T cells
	α,β or γ,δ		Th‐1	Mediates DTH responses
	α,β	CD8		Lyses‐infected cells	IL −2, IFNγ, TNFα

DTH, delayed‐type hypersensitivity; IFN, interferon; IgA, immunoglobin A; IgD, immunoglobin D; IgE, immunoglobin E; IgG, immunoglobin G; IgM, immunoglobin M; IL, interleukin; TNF, tumour necrosis factor.¹⁰