This electron micrograph (EM) illustrates the uptake of iccosomal antigen at 5 days after injection of the antigen, HRP. By this time all iccosomes appear to have been endocytosed. The typical morphology of iccosomes is rapidly destroyed after ednocytosis and only the HRP antigen can be visualized histochemically in the cytoplasm of these germinal center B cells [See arrows indicating the electron dense (black) antigen. SEE LEFT EM]. Also, at this time the proliferative activity of these B cells becomes prominent. At higher magnification [SEE RIGHT EM] the path of the endocytosed antigen can be followed to the Golgi apparatus This high power EM on the right shows that the endocytosed antigen is transported in vesicles (black arrows). The vesicles migrate toward the Golgi located between the nucleus and the centriole and are indicated by the white arrows. Note that the antigen becomes associated with the Golgi membranes which typically function in the transport of newly formed membranes to the surface of the cell. The vesicles sent to the surface and probably contain the processed antigen for re-expression and presentation to helper T cells. For more detail on the morphology see the original paper: Click on the blue reference [REF] button.