Human platelet lysate enhances the proliferative activity of cultured human fibroblast-like cells from different tissues Vicente Mirabet Æ Pilar Solves Æ M a Dolores Min ˜ana Æ Araceli Encabo Æ Francisco Carbonell-Uberos Æ Amando Blanquer Æ Roberto Roig Received: 26 December 2006 / Accepted: 25 May 2007 / Published online: 20 June 2007 Ó Springer Science+Business Media B.V. 2007 Abstract Several studies have shown the presence of fibroblast-like cells in the stromal fraction of different tissues with a high proliferative and differ- entiation potential. Platelet alpha granules contain growth factors released into the environment during activation. The effects of different supplements for culture medium (human serum, bovine serum and platelet lysate) on cultured human fibroblast-like cells from bone marrow, adipose tissue, trabecular bone and dental pulp have been compared. Expression of typical stromal and hematopoietic markers was analyzed and proliferative rates were determined. Flow cytofluorometry showed a homogenous pattern in serial-passaged cells, with a high level of stromal cell-associated markers (CD13, CD90, CD105). The presence of platelet lysate in culture media increased the number of cell generations obtained regardless of cell source. This effect was serum-dependent. Cell- based therapies can benefit by the use of products from human origin for ‘‘ex vivo’’ expansion of multipotent cells. Keywords Platelet lysate Á Cell proliferation Á Human fibroblast-like cells Á Bone marrow Á Adipose tissue Á Trabecular bone Á Dental pulp Á Human serum Introduction The presence of pluripotent and highly proliferative cells has been described in different human tissues: bone marrow (Hung et al. 2002; Pittenger et al. 1999; Reyes et al. 2001; Sekiya et al. 2002; Suva et al. 2004), adipose tissue (Gronthos et al. 2001; Halvorsen et al. 2001; Zuk et al. 2001; Planat- Benard et al. 2004), trabecular bone (Sakaguchi et al. 2004; Tuli et al. 2003), dental pulp (Gronthos et al. 2000; Miura et al. 2003), umbilical cord blood (Bieback et al. 2004; Erices et al. 2000; Lee et al. 2004) and peripheral blood (Zvaifler et al. 2000; Zhao et al. 2003; Yeh et al. 2003). In order to achieve sufficient amounts of these pluripotent cells for clinical purposes (Korbling and Estrov 2003) their ex vivo expansion is required (Horwitz et al. 2002; Le Blanc et al. 2004). Most culture models use fetal calf serum (FCS) as a supplement of culture media to increase the stem cell popula- tion in vitro. However, it has been determined that 7–30 mg of FCS proteins are associated with a standard preparation of 100 million human mesen- chymal stem cells (Spees et al. 2004), and it may involve a humoral response (Horwitz et al. 2002). Moreover, these authors have shown that the V. Mirabet (&) Á P. Solves Á F. Carbonell-Uberos Á A. Blanquer Á R. Roig Centro de Transfusio ´n de la Comunidad Valenciana, Avenida del Cid, 65-A, 46014 Valencia, Spain e-mail: mirabet_vic@gva.es M. D. Min ˜ana Á A. Encabo Fundacio ´n Hospital General Universitario de Valencia, Valencia, Spain 123 Cell Tissue Banking (2008) 9:1–10 DOI 10.1007/s10561-007-9048-x