Supplementary Material for: New Description of Telocyte Sheaths in the Bovine Uterine Tube: An Immunohistochemical and Scanning Microscopic Study

Telocytes are a special type of interstitial cells characterized by
distinctive cellular extensions with alternating thin segments
(podomers) and dilations (podoms). Telocytes establish contact with
various cells and structures, but their role in the regulation of the
function of many cell types is still obscure. The aim of the current
study was to investigate the morphology, histochemistry, and
immunohistochemistry of telocytes, and their distribution, organization,
and morphometric measurements in different layers of the adult bovine
uterine tube. Telocytes showed positive immunostaining for CD117, S-100
protein, vimentin, desmin, α-smooth muscle actin, tubulin, laminin,
estrogen receptor-α, and progesterone receptor. They were organized in
different types of sheaths: subepithelial, inner/outer perimuscular, and
intramuscular sheaths. Telocytes were scattered in the lamina propria,
in the muscular layer, and the serosa. According to their size, they
were grouped into different types of telocytes: small, large, and giant
telocytes. Small telocytes were the most common type and located in all
layers; large telocytes were observed in the epithelium, lamina propria,
and inner/outer perimuscular and intramuscular sheaths, and giant
telocytes were found in the external layer of the outer perimuscular
sheath. Telocytes were connected by thin and thick telopodes
(fenestrated membranes). Fenestrated membranes enabled connections
between telocytes along the entire muscular wall of the uterine tube.
Telocytes established an extensive biological network of different types
of cells and structures, including epithelial, muscular, and mast
cells, blood vessels, glomus, and nerve fibers. We hypothesize that
telocytes help to organize the functional coordination between different
types of cells in the uterine tube.