GT-T551isaculturemediumideallysuitedforexpansionofhumanTlymphocytes(Tcells).Itissupplementedwithhumanalbumin(pharmaceuticalgrade),recombinanthumaninsulin,L-glutamine,andstreptomycin;noadditionalproteinsorgrowthfactorsareadded.Themediumcansupportstablegrowthinthepresenceorabsenceofserum.Anti-CD3/IL-2T-cellactivationcanalsobeperformedinthismedium(Wangetal.2013;Aietal.2014;Dodoetal.2014).Whenusingthisactivationmethod,theadditionalpresenceofRetroNectinreagentenhancestheproliferationofTcells(Yuetal.2008;Ishikawaetal.2014;Hosoietal.2014;Sakamotoetal.2015;Lietal.2015)andresultsinanexpandedcellpopulationthatshowsahigherproportionofnaïveTcellsthananti-CD3antibodystimulationalone(Hosoietal.2014).