In lymph nodes the cells, now known as tissue dendritic cells or interdigitating cells, may efficiently present antigen if they encounter the right T cell. They cannot present antigen to T cells but are important in developing responses by B cells. There are three types of granulocyte distinguished according to their histological staining patterns. Neutrophils , also known as polymophonuclear leukocytes, express receptors for immunoglobulin and complement and are involved in the acute inflammatory response. Eosinophils carry receptors for IgE, are involved in the destruction of IgE coated parasites, such as helminths, and contribute to the immediate hypersensitivity response to allergens.
Basophils are the circulating counterpart of tissue mast cells .
They express high affinity receptors for IgE and are stimulated to secrete the chemicals responsible for immediate hypersensitivity following antigen induced aggregation of these receptors. Lymphoid Tissue Lymphoid tissue is conveniently divided into the central or primary and peripheral or secondary organs. Central organs include the bone marrow and thymus. Lymphocytes, monocytes and granulocytes derive from precursor stem cells in the bone marrow. B lymphocytes migrate directly from marrow to the peripheral lymphoid tissue whereas T lymphocytes undergo further maturation in the thymus.