I had did it with Human AB+ Serum which should be from the non edicted and health person who had no history of antimalarials or any kind of antibiotics from last 3 months.
apart of it you can check the compatible human serum with any group with the infected RBCs you have.
There are some Commercial serums also available but for the continuous culture i suggest hAB+ Serum.
These are the way for the selection of Serum but apart of it the selection of Media is also important. You should select the media with Hepes where Biocarbonate is freshly prepared and added, I had used RPMI 1640 from Invitrogen that was the best in my use which was brought in powder form and was made in complete asceptic condition and antibiotic was added according to the load of contamination but streptomycin and penstrep like antibodies were avaoided because it was found effective to the parasite.
apart of it if you thing i can help you in some more things regarding pf culture than i would be my pleasure.
i don't suggest pooled serum i hope you mean to say the serum which is collected from number of donars but in that clotting may take place because of the factors. but really speaking i had never taken chance with my precious samples of culture. If you have enough samples just go and check and please kindly let me know that will be an intresting to note our..