The macrophage is a relatively large, p____c cell. They play an essential role in
many different types of i____e and i_____y reactions. Macrophages have
m____ple functions. They are important in killing intracellular p____s and t__or
cells. They act as s____rs for f___n material and ext____r debris. They also act
as regulators of immune r____ness. The major functional roles of macrophages in
the immunological process are antigen pr____ing and antigen pr____tion.
An additional function attributed to macrophages is the production of factors that
influence the activity of l____cytes. Macrophages secrete over 50 products, many
related to i____y. These include enzymes, plasma proteins (including c____tion
proteins and c____ment components), lipids, and factors regulating c____r
functions. One of the factors regulating cellular functions is i_____n-1, which has
a number of important effects. For example, interleukin-1, also called lymphocyte-
a______ing factor (LAF), induces lymphocytes to produce i_______n-2, which in
turn encourages short-term proliferation of l_____cytes.
Antigen bound to macrophage s_____s or i______d by macrophages is more i
mmunogenic than antigen that has not been "processed" by macrophages.
Macrophages function in processing the a____n and subsequently pr_____ing it to
lymphocytes. It is thought that processing may ex___e determinants otherwise
not available or change pre-existing d____nants into a r____able form.
Once the antigen is processed by the macrophage, it is p____ted to lymphocytes.
There is evidence that small amounts of antigen bound to the macrophage s____e
are important in the i____ction phase of the immune response. Evidence also
suggests that macro___e processing is not essential for all antigens. The size of
the antigen may determine whether macrophage processing is n____y.
A common opinion about the interaction of macrophages with B and T cells is that
macrophages d___t complex antigens to make them "palatable" for _ cells.
Another concept is that macrophages ingest a___s and then manufacture some
informational type of r____c a__d which is transferred to B l____s and triggers