Page 277 - Veterinary Immunology, 10th Edition

many of the details of DC function have been worked out in
VetBooks.ir humans and mice. It must not be assumed that the structure and

functions of DCs in domestic mammals are identical.

FIG. 10.3 The origins and diversity of DCs. One subpopulation,
the plasmacytoid DCs, originates from lymphoid precursors. The
second major subpopulation arises from myeloid precursors and is
probably derived from monocytes. These monocyte-derived cells
differentiate into classical DCs follicular DCs and Langerhans cells.

As pointed out earlier, the adaptive immune system mounts two
types of response: the antibody-mediated and cell-mediated
responses. The type of response mounted is determined by the type
of helper T (Th) cells activated when an antigen is encountered.
Thus there are multiple types of helper cells (see Fig. 14.12). One

major type, helper 1 cells (Th1 cells), stimulates cell-mediated
immune responses designed to protect animals against intracellular
organisms. The other major type, helper 2 cells (Th2 cells),

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