I recently induced tumors in a xenograft model MDA-MB-468 using Athymic nude mice in the dual flanks.
I used BD matrigel basement membrane matrix at high concentration.
The cells were at a concentration of 4x10^6 with the matrigel.
The volume I used was about 200uL of the cells to total the 4million, combined with 200uL of the matrigel.
The suspension was very gel like, and everything was kept on ice, and syringes were loaded prior to inoculation.
I injected the cells subcutaneously on the mice, with the 400uL suspension.
What was observed the first day was a gel like aqueous suspension in the SC layer of the mice, some of it came out.
I have observed the mice daily since the injection, while the size has shrunk a bit, the size is still quite a decent size.
I am not sure if this is a tumor? Actually I anesthetized the mice to check the feel , and it seems to be a hard solid lump after 7 days.
The sizes range from around 100-150mm^3.
Could the tumor actually form this quick, should we wait another week or two to begin treatment? If not, what do you suspect happened?
Thanks so much