LOCALIZATION OF THE TRANSMEMBRANE-4 SUPERFAMILY (TM4SF) MEMBER PETA-3(CD151) IN NORMAL HUMAN TISSUES - COMPARISON WITH CD9, CD63, AND ALPHA-5-BETA-1 INTEGRIN
Pm. Sincock et al., LOCALIZATION OF THE TRANSMEMBRANE-4 SUPERFAMILY (TM4SF) MEMBER PETA-3(CD151) IN NORMAL HUMAN TISSUES - COMPARISON WITH CD9, CD63, AND ALPHA-5-BETA-1 INTEGRIN, The Journal of histochemistry and cytochemistry, 45(4), 1997, pp. 515-525
It has recently been shown that several members of the tetraspan super
family, including CD9 and CD63, associate with each other and with bet
a 1 integrins. In this study, we examined the distribution of a recent
ly identified tetraspan, PETA-3 (CD151), and of CD9, CD63, alpha 5 bet
a 1, and the integrin beta 1 chain in normal human tissues by the indi
rect immunoperoxidase and alkaline phosphatase-anti-alkaline phosphata
se techniques. PETA-3 showed a broad distribution and was expressed by
endothelium, epithelium, Schwann cells, and dendritic cells and by sk
eletal, smooth, and cardiac muscle. Expression in skin was mostly rest
ricted to the basal cells of the epidermis and was downregulated on di
fferentiation. In the small intestine, PETA-3 was expressed by crypt a
nd villous enterocytes with a mostly basolateral distribution, but was
not detectable on the brush border. CD9 was expressed on the plasma m
embrane of enterocytes in crypts and at the bases of the villi whereas
CD63 demonstrated a unique granular appearance concentrated in the ap
ical cytoplasm below the brush border. The findings of this study show
co-localization of PETA3 with CD9, CD63, alpha 5 beta 1, and beta 1 i
n particular tissues, demonstrating that tetraspan/integrin complexes
may occur. However, the lack of co-localization of these antigens in o
ther tissues also implies distinct roles for these molecules.