The
Fc receptors of IgG (a link between humoral and cellular immunological responses), are highly interested in the etiology and pathogenesis of autoimmune diseases and Fc gamma receptors are encoded in the long arm of chromosome 1 (4, 5).
TTI-622 consists of the same CD47-binding domain of human SIRPa as TTI-621 but linked to an IgG4 Fc region, which has a more restricted ability to engage activating
Fc receptors. It is expected to have a different pharmacologic profile than TTI-621 and is being developed primarily for combination therapy.
M230, a selective immunomodulator of
Fc receptors and the multiple Fc domains of ICs aggregate Fc?
Hellman, "
Fc receptors for immunoglobulins and their appearance during vertebrate evolution," PLoS One, vol.
Nonneutralizing antibodies do not directly interfere with TNF binding but may compromise therapeutic efficacy by contributing to enhanced clearance of the drug from the circulation through immune complex formation and binding to
Fc receptors on phagocytic cells (14).
The effects of intravenous immunoglobulin include complex mechanisms, but it exerts its essential action by eliminating the non-specific
Fc receptors found in the mononuclear phagocytic system or by inhibiting binding of immune complexes to
Fc receptors in the cells.
Additional functional variation exists as a result of the differential affinities and cellular expression that occurs within the family of
Fc receptors and their variants.
Unlike IgG, IgY antibodies do not bind to bacterial
Fc receptors, such as staphylococcal protein A or streptococcal protein G (JENSENIUS et al., 1981).