Dr. Anderson is interested in how two families of IgG Fc receptors work, specifically, how one family mediates inflammatory and protective effects of IgG antibodies; and how another binds both IgG and albumin, extending the half-lives of these two molecules by protecting them from degradation, transporting (at least IgG) across the placenta from maternal to fetal circulation.
IgG antibodies bind antigens to form immune complexes that interact with the plasma membranes of several types of cells to trigger a number of inflammatory and protective biologic processes. These processes include the endocytosis of antibody-coated particles such as bacteria or viruses by cells, the stimulation of secretion of inflammatory mediators, the cell-mediated killing of antibody-coated target or tumor cells, and the modulation of the immune responses by lymphocytes and other cells of the immune system. Mediating these processes in man are three distinct classes of integral membrane Fc receptors which bind IgG (FcgR) immune complexes. These receptors, encoded by eight genes on chromosome 1, constitute a small subfamily within the immunoglobulin gene superfamily. Upon clustering by immune complexes the receptors trigger intracellular enzymatic cascades by activating non-receptor tyrosine kinases and phosphatases. Dr. Anderson's lab uses the methods of immunology, cell biology, molecular biology, and biochemistry to study these processes.
It is apparent that IgG is transported across the placenta from maternal circulation to the fetus, conveying the full complement of mother's protective antibody, by a transporter molecule with high affinity for IgG (FcRn) that is not a member of the family of classical FcgR described above. This molecule, present in the trophoblast of the placenta and in many cells of the body throughout life, is also responsible for protecting IgG from its normal catabolic fate, accounting for the long lifespan of IgG. Dr. Anderson's lab is interested in how this receptor works in health and disease. We have recently found that FcRn binds albumin and rescues it from a degradative fate, extending its half-life to near that of IgG.