An electron micrograph (EM) showing an antigen transport cell (ATC) in the process of passage through a pore in the floor (FL) of the subcapsular sinus (SS). This ATC passes into the cortex of a popliteal lymph node (LN) shortly after the subcutaneous introduction of antigen into the foot of an immune animal. The antigen in the form of immune complexes is bound to the surface of the process of this ATC. These immune complexes can be seen as black (electron dense) precipitate on the surface of veil-like processes which form a "catcher's-mitten" (P) that extends into the lumen of the SS. The veils coated with the Ag-Ab-C' complexes appear to be held together by the immune complexes. This kind of ATC processes can bee seen frequently in the act of being pulled through the pores in the floor of the SS. For more information consult our publication (click the REF button below).