Infection efficiency of non-adherent cells - (Nov/03/2006 )

Does anybody has some tips for increasing efficiency of infection on primary cells in non-adherent plate. The cells are spin-infected at 2500 rpm for an hour.

Have you tried addition of polybrene? Haven't tried it myself, but I've read (in severall publications, so I believe it to be reliable) that it helps for certain virusses (not sure if it will work for your specific case though).
Spinoculation (or spininfection) is supposed to increase infection efficiency as well, do you notice an increase?

If you are using retroviruses, polybrene is definitely a must. Additionally, you can try using a different virual envelope such as VSV-G since it is not as dependent of the expression of the receptor.

Along with the supernatent I use Protamine Sulphate and HEPES. I guess it is similar to using polybrene!