PERSONAL DE APOYO
DE LEON Romina Soledad
congresos y reuniones científicas
Título:
Modulation of osteoclast differentiation by placental regulatory factors.
Autor/es:
CUSTIDIANO A.; URTENECHE I.; SACERDOTI F.; DE LEÓN R.; GENTILE T.; CANELLADA A.
Lugar:
BUENOS AIRES, ARGENTINA
Reunión:
Congreso; The 3rd Latin American Congress of Autoimmunity (LACA 2010); 2010
Resumen:
During
rheumatoid arthritis, macrophages differentiate into osteoclasts and
bone destruction occurs. We demonstrated that extracts from mouse
placenta (EPs), containing Th1 and Th2 cytokines, regulate the
osteoclast differentiation of RAW 264.7 macrophages. Now we analyze,
whether IL-10, TGF-beta, as well as the NFATc1 transcription factor are
involved in such effect. Placental extracts were obtained at 7 days of
pregnancy (EP7). RAW cells were cultured with RANKL and M-CSF (RM) in
the presence or absence of EP7, and neutralizing antibodies (NA) against
IL-10 and TGF-beta; the differentiation of the cells was determined by
assessing multinucleated, tartrate resistent acid phosphatase positive
cells (TRAP+), using a commercial kit; and matrix metalloprotease (MMP)
activity by zymogram. The effect of EP7 on NFATc1 expression
/phosphorylation was assessed by western blot. EP7 inhibited the
RM-induced MMP activity and TRAP+ (inhibition vs RM: 68%, p<0.001 and
91%, p<0.001, respectively). Pre-incubation of RAW cells with
a-IL-10 NA reverted the inhibitory effect of EP7 on MMP activity
(a-IL10+RM vs a-IL10+RM+EP7, p>0.05) while the inhibition of TRAP+
was not affected (a-IL10+RM vs a-IL10+RM+EP7, p<0.01). Pre-incubation
with a-TGF-beta NA reverted the inhibitory effect of EP7 on both, the
MMP activity and the TRAP+ (a-TGF-beta+RM vs a-TGF-beta+RM+EP7,
p>0.05). EP7 inhibited in 79 % the expressión of NFATc1 in cells
cultured during 4 days with RM (p<0.001); nevetheless, the NFATc1
dephosphorylation induced by 2 h-treatment of the cells with RM was not
affected by EP. We propose that downregulation of NFATc1 expression by
EP7 is involved in the inhibition of the RM-induced osteoclast
differentiation of RAW cells. TGF-beta participates in the inhibition of
MMP and TRAP+. The inhibitory effect of IL-10 on MMP activity, was not
enought to inhibit cell differentiation, since a-IL-10 NA was not able
to revert the inhibition by EP7 of RM-induced TRAP+