TCID - (Dec/01/2009 )

Hi everyone,

I'm new in virology and just started to work on murine cytomegalovirus.

Since I can't measure the titer using plaque assay as my 3T3 cells didn't form plaques. I've tried many conditions: switch to NCS instead of FBS, centrifuge to enhance infection, tried 50-100% confluent monolayer...etc. I still can't see any plaque. Is anyone can help troubleshoot with me?

Now I'm planning to buy virus from company (ATCC) for in vivo experiment as I hope to have consistent infection condition. However, the titer from company is in TCID instead of pfu. Does anyone of you can help with the conversion? The MCMV they are providing is VR-1399: 10(4.75)TCID<50>/0.2 ml

Any opinion/suggestion for in vivo mouse virus infection may also helpful to me.

Thank you very much!!

The conversion from TCID50 to PFU is different for every virus and for every virus stock. In my humble opinion, I would recommend sticking with TCID50 dosing in your in vivo studies. I regularly give my mice specific TCID50 units of virus, especially in the strains that do not plaque.