Endosome Forms in the APC Posted by Shayna Matson Full size 1237 × 1122 pixels Playdoh Model for Antigen Presenting Pathway and Immunodominance 3. Once the HA protein is phagocytized, an endosome forms and enzymes start digesting the protein right away. Previous image Next image Leave a Reply Cancel replyYour email address will not be published. Required fields are marked *CommentName* Email* Website Save my name, email, and site URL in my browser for next time I post a comment. Δ