The present invention addresses the problem of providing a method for promoting the uptake of an antigen into a cell by an antigen-binding molecule; a method for increasing the frequency of binding to an antigen by one antigen-binding molecule; a method for promoting a reduction in plasma antigen concentration by the administration of an antigen-binding molecule; a method for improving the retention of an antigen-binding molecule in plasma; an antigen-binding molecule which promotes the uptake of an antigen into a cell; an antigen-binding molecule such that the frequency with which the molecule binds to an antigen is increased; an antigen-binding molecule capable of promoting, by the administration thereof, a reduction in plasma antigen concentration; an antigen-binding molecule which has improved retention in plasma; pharmaceutical compositions comprising such antigen-binding molecules; and methods for producing the foregoing. The inventors discovered that the problem can be solved by using an antigen-binding molecule having a calcium-dependent antigen-antibody reaction.