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 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