siRNA knockdown of Tac1 abrogates the promotion of VEC proliferation and tube formation by inflamed TG neurons. (A) TG neurons derived from mice with DED were transfected with control non-target or Tac1 siRNA. Tac1 mRNA expression was reduced by 87% (n=4). (B) VEC proliferation was reduced when co-cultured with TG neurons transfected with Tac1 siRNA, compared with control siRNA (n=4). VEC proliferation (C, n=8) and tube formation (D, E, F n=5) were reduced when VEC were cultured in the conditioned media derived from DED TG neurons transfected with Tac1 siRNA, compared with those transfected with control siRNA. *p<0.05, **p<0.01.