Figure 1

(A) Locations where primo nodes were taken for the current study. The OS-PVS formed a network on the surfaces of abdominal organs. PNs with cucumber shapes of various sizes were floating in the peritoneal fluid in the abdominal cavity: red, large-size PNs, orange, medium-size PNs, and green, small-size PNs. (B) Large-size OS-PN (arrow) around the small intestine of a rat. This is an in vivo in situ stereomicroscopic image. (C) The OS-PN in (B) was harvested and put on a petri dish. (D) Another specimen of a medium-size OS-PN which was harvested from around the small intestine. Two PNs (arrows) were connected by a primo vessel. OS-PN = organ surface primo node; OS-PVS = organ surface primo vascular system; PN = primo node; PV = primo vessel.