Recently, these "strange things" have appeared in my 6 cell lines that were in cell culture at the same time. At first, we thought it could be some type of microorganism contamination, but they did not expand (even after 1 week) and the cells did not seem to be affected. In addition, we had frozen some vials without realizing the presence of these changes and days later we thawed the vials of two of these cells (HSC-3 and HN494) and continued to observe these changes. They do not seem to increase in quantity, but perhaps they are increasing in size, because we noticed some smaller and others larger. It also seems that some of them are loose in the middle but others seem to be stuck to the cells. We noticed them both in bottles (T75) and in plates (P100, P6 and P60).
Other bottles and plates from other people who shared the same incubator did not show these changes. And 2 other cell lines that I manipulate also did not present these alterations, although they used the same medium as SCC9 and HSC3 (DMEMF12 medium), but these 2 lineages are exposed weekly to radiation (they are in the process of inducing resistance to radiation). .
Has anyone noticed this type of change? Could you tell me if it is some contamination by a microorganism? Or perhaps an alteration in the supplementation items?
The following cells that presented alterations and their respective media used.
- HFF-2 (fibroblasts) and Head and neck Normal Oral fibroblasts (HN494 and HN521) -> DMEM medium supplemented with FBS, antibiotic/antimycotic, L-glutamine, pyruvate and non-essential amino acid;
- SCC-9 and HSC-3 -> DMEM-F12 medium supplemented with FBS, antibiotic/antimycotic and hydrocortisone
- NK92MI (NK cells) -> alpha-MEM medium with antibiotic/antimycotic, supplemented with FBS, horse serum, inositol, folic acid, non-essential amino acid and methyl-B-mercaptoethanol.
Note:
- the only item that is used in all 6 different cells is PBS, which is prepared and autoclaved weekly.
- The laboratory air conditioning is facing problems and its temperature constantly remains around 30ºC.
I appreciate your considerations and contributions.
The *other things" observed could,
1. Protein precipitation which can be caused by the high temperature ~30°C. At this temperature, protein can undergo cellular precipitation.
2. Precipitation of supplement items due to improper mixing
3. It could be extra cellular vesicles or some apoptic cell , which can be caused by cellular stress due to the temperature
4. It night also be plastic fragments from plastic wares
Suggestion
Try microscopic examination to evaluate the presence of absence of mycoplasma and dormant fungi.
- Badges
- Science topic
- Similar topics
- Medicine
- Disease
- Infectious Diseases