Figure 3.

Primocin-containing washing solutions protect from bacteria contamination during organoids derivation from colorectal cancer patients. (A) Representative micrograph of P115 PDO cultures acquired at the microscope at day 3 and day 5. The first 2 micrographs acquired at day 5 refer to the contaminated PDO cultures and the darker area indicated by the red arrow indicates areas with high concentration of bacteria. The yellow color of the medium indicates high metabolic activity in the well due to bacteria proliferation. At high magnification, it is possible to appreciate the shape of chain-forming bacilli. (B) Total events observed for each washing condition. The numbers on top of the bars indicate the percentage of contaminated samples while the bars represent the absolute number of observed contaminations for each condition (within a total of 16). (C) Matrigel drop degradation due to bacterial contamination in P107 PDO culture. Red arrows at day 4 indicate the residue of Matrigel drop borders left after degradation, while the higher black background indicates a diffusion of bacteria.