Early in vivo and in vitro effects of amelogenin gene splice products on pulp cells.
Recombinant amelogenin gene splice products A+4 and A-4, implanted in the pulp, induce the recruitment, proliferation, and differentiation of reparative cells. Our aim was to investigate the precocious events occurring in the pulp 1 d and 3 d after implantation of agarose beads alone or loaded with A+4 or A-4. Proliferation and cell recruitment towards an odonto/osteogenic phenotype were visualized by detection of the proliferation cell nuclear antigen (PCNA) and RP59. After implantation of beads alone or loaded with A+4, at day 3, pulp cells were moderately immunopositive for osteopontin (OP), whereas labeling was strongly positive upon treatment with A-4. Dentin sialoprotein (DSP) labeling was not detectable. Parallel in vitro studies were carried out on odontoblastic and mesenchymal progenitor cells in order to evaluate the effect of the amelogenin peptides on the expression of a series of marker genes involved in the odontoblastic/osteogenic/chondrogenic differentiation pathways. Altogether, our results suggest that the 'signaling' effects of the amelogenin peptides A+4 and A-4 may differ according to the type of target cells, their stage of differentiation, the time of treatment, and the type of amelogenin peptide (A+4 or A-4).
Lacerda-Pinheiro
Sally
S
Laboratoire de Différentiation Cellulaire et Prions - UPR1983 CNRS, Villejuif, France.
Jegat
Nadege
N
Septier
Dominique
D
Priam
Fabienne
F
Bonnefoix
Mireille
M
Bitard
Juliette
J
Kellermann
Odile
O
Tompkins
Kevin
K
Veis
Arthur
A
Goldberg
Michel
M
Poliard
Anne
A