, antigens are captured and concentrated in secondary
lymphoid organs through which naïve lymphocytes
circulate, thus increasing the likelihood of a lymphocyte
finding antigens it can recognize. Microbes and their protein
antigens are captured by DCs that are resident in epithelia
and tissues. These cells carry their antigenic cargo to draining
lymph nodes (Fig. 6.10). Here the antigens are processed
and displayed complexed with MHC molecules on the cell
surface, where the antigens are recognized by T cells.
, Even before the antigens of a microbe are recognized by
T and B lymphocytes, the microbe elicits an immune response
through pattern recognition receptors expressed on innate
immune cells; this is the first line of defense that also serves
to activate adaptive immunity. In the case of immunization
with a protein antigen, microbial mimics, called adjuvants,
are given with the antigen, and these stimulate innate
immune responses. During the innate response, the microbe
or adjuvant activates antigen-presenting cells to express
molecules called costimulators and to secrete cytokines that
stimulate the proliferation and differentiation of T lympho
,
lymphoid organs through which naïve lymphocytes
circulate, thus increasing the likelihood of a lymphocyte
finding antigens it can recognize. Microbes and their protein
antigens are captured by DCs that are resident in epithelia
and tissues. These cells carry their antigenic cargo to draining
lymph nodes (Fig. 6.10). Here the antigens are processed
and displayed complexed with MHC molecules on the cell
surface, where the antigens are recognized by T cells.
, Even before the antigens of a microbe are recognized by
T and B lymphocytes, the microbe elicits an immune response
through pattern recognition receptors expressed on innate
immune cells; this is the first line of defense that also serves
to activate adaptive immunity. In the case of immunization
with a protein antigen, microbial mimics, called adjuvants,
are given with the antigen, and these stimulate innate
immune responses. During the innate response, the microbe
or adjuvant activates antigen-presenting cells to express
molecules called costimulators and to secrete cytokines that
stimulate the proliferation and differentiation of T lympho
,
