Is TrpM5 a reliable marker for chemosensory cells? Multiple types of microvillous cells in the main olfactory epithelium of mice

Table 3 Antibody pattern in microvillous cells

	TrpM5a Type MV cells	TrpM5b Type MV cells	Non-TrpM5 Type MV cells	Ciliated ORNs	Other tissue controls
TrpM5	+++	+++	-	+*	-
Calbindin	-	-	?	++
Calretinin	-	-	?	++
Chromogranin A	-	-	-	-	some cells in VNO
CK18	-	-	++	-
Espin	+++	+++	+++	-
CGRP	no contact	no contact	?	no contact	contact to SCCs
Gq/11	-	-	++	-
IP3R3	-	-	+++	-
Na⁺, K⁺-ATPase	-	-	-	-	nerve fibers, olfactory bulb
NSE	-	-	?	++
OMP	-	-	?	+++
P2X2	-	-	-	-	+ **
P2X3	-	-	+	+
PDE2A	-	-	+	++***
PGP9.5	-	-	?	+++
PLC beta2	-	-	+	+
Substance P	no contact	no contact	?	no contact	contact to SCCs
SNAP 23	-	-	?	-	synapses in muscle tissue
SNAP 25	-	-	?	-	synapses in muscle tissue
SUS-1	-	-	-	-	supporting cells
SV2	-	-	++	-	nerve fibers, synapses in various tissues
Synaptophysin	-	-	++	++
TrpC6	-	-	++***	-
VAChT	-	-	-	-	+ in SCCs
Villin	+++	+++	+++	-

+++ = abundant; ++ = some; + = few; - = absent; ? = possible but not confirmed by electron microscopy
MV = microvillous cells
* weakly expressed in some ORNs in limited areas
** P2X2 positive cells are present in the thin epithelium of the turbinates which resemble solitary chemosensory cells (SCCs)
*** in limited areas

ISSN: 1471-2202