%0 Journal Article
%T VACUTAINER£¿ CPT£¿ and Ficoll density gradient separation perform equivalently in maintaining the quality and function of PBMC from HIV seropositive blood samples
%A Joyce J Ruitenberg
%A Candice B Mulder
%A Vernon C Maino
%A Alan L Landay
%A Smita A Ghanekar
%J BMC Immunology
%D 2006
%I BioMed Central
%R 10.1186/1471-2172-7-11
%X The results indicate that cryopreserved PBMC samples tested for CMV- and HIV- specific interferon-gamma (IFN¦Ã) expression performed equivalent to the respective fresh PBMC processed under both collection conditions. Compared to fresh PBMC, the viability was significantly lower for cryopreserved PBMC derived using Ficoll, although it was never less than 90%. There were no significant differences in the IFN¦Ã response, viability, or recovery between cryopreserved PBMC derived by Ficoll and by CPT.These data suggest that CPT is an efficient system for the collection and cryopreservation of functionally active HIV+ PBMC, as well as a viable alternative to Ficoll gradient separation.Therapeutic HIV vaccine clinical trials typically involve the collection of whole blood specimens from HIV+ patients at multiple study sites, and the shipment of collected samples to a central location for PBMC isolation and evaluation [1,2]. Generally, clinical researchers prefer to harvest and cryopreserve PBMC from blood samples collected at pre-determined time points, and perform assays at a later date or after a number of samples have been accumulated. Cryopreservation and the evaluation of samples at a central location have become standard procedures for minimizing operator dependent variability and to improve the precision and accuracy of immunoassays [2,3]. There are two typical whole blood collection options available to clinical investigators, (1) collection in evacuation type/VACUTAINER£¿ tubes and (2) collection in VACUTAINER£¿ CPT£¿ (Cell Preparation Tube). With collection method (1), samples are collected and shipped to a central location for PBMC isolation using Ficoll density gradient separation, while with collection method (2) whole blood samples are collected, and processed by centrifugation at the collection site, and then shipped to a central location for PBMC recovery.Previous studies have shown that many factors can have an effect on T cell functional responses including sh
%U http://www.biomedcentral.com/1471-2172/7/11