Patient's blood was evaluated for increase in titers of hfSC specific antibodies and for increase in antibody-dependent cell-mediated cytotoxicity after implantation as compared to baseline values. Samples were drawn one month prior to cell implantation, and then one month and six months after surgery. Whole blood specimens were collected from each patient and processed as serum one and six months post-grafting using the lipophilic membrane dye PKH67 (Sigma-Aldrich) as described by the manufacturer for cell tracking in immune response and cytotoxicity assays by flow cytometry [30,31]. Cytotoxicity assay was performed with 100:1, 50:1, and 25:1 effector to target ratios.