Cell-cell interaction between acinar-like cells and islet endocrine cells encapsulated by common BMs.

<p><b>A:</b> A desmosomal junction (arrowhead) is observed between acinar-like cells (AC) and alpha cells (A), which are encapsulated by common BMs and ECM. <b>B</b>: Coated-pit-like structure is observed between an acinar-like cell (AC) and an alpha cell (A) touching directly and covered by common BMs (arrows). Inset shows a magnified view of the coated-pit-like structure. <b>C</b>: Excretion of vesicles from acinar-like cells (AC) to a beta cell (B). Note the vesicular membrane of the AC is dissolved (arrow), and the vesicular content is released to the beta cell (B) touching it. <b>D1</b>: Exocytotic features of vesicles in acinar-like cells (AC) to beta cells (B), which are in contact with each other. Arrowhead indicates BMs/ECM encapsulating acinar-like cells and beta cells, V: vasculature. <b>D2:</b> Higher magnified view of D1. The vesicle is internalized to the beta cell. AC: acinar-like cell, B: beta cell. <b>E:</b> Vesicles of acinar-like cells (AC) are internalized to touching alpha cells (A) and beta cell (B) shown by arrows. Arrowheads indicate BMs/ECM surrounding beta cell (B), alpha cell (A), and acinar-like cell (AC). Inset shows magnified view of (E). LB: lipofuscin body, ER: endoplasmic reticulum.