Influence of patient related factors on number of mesenchymal stromal cells reached after in vitro culture expansion for clinical treatment.

Background: Number of stromal cells injected in patients with ischaemic heart disease (IHD) may be of importance for the treatment efficacy, which in turn may be influenced by various patient-related factors. In this study, we investigate whether patient-related factors influence the number of autologous stromal cells reached after in vitro culture expansion for clinical therapy.

Methods: Culture expansion data from 111 patients with IHD treated with autologous stromal cells in three clinical trials were used. We correlated the final cell count after two passages of cultivation with different patient factors.

Results: There was a significant relation between body mass index (BMI) and the number of adipose derived stromal cells (ASCs) reached after culture expansion and for all patients included into the three studies (r = 0.375, p = .019 and r = 0.200, p = .036, respectively). Moreover, there was a significantly higher number of ASCs reached in patients with hypertension compared to those without hypertension and for all patients overall (68.8 ± 39.6 × 10 vs. 39.1 ± 23.6 × 10, p = .020 and 62.0 ± 55.0 × 10 vs. 29.0 ± 19.3 × 10, p < .001, respectively). The same tendency was seen with bone marrow derived mesenchymal stromal cells (MSCs) in patients with hypertension compared to those without hypertension (58.4 ± 61.8 × 10 vs. 22.6 ± 13.3 × 10, p < .001) and in males compared to females (56.4 ± 61.5 × 10 vs. 30.9 ± 27.9 × 10, p = .041). Moreover, a significant negative correlation between left ventricular ejection fraction and number of MSCs was found (r = -0.287, p = .017).

Conclusions: Patient related factors such as BMI, hypertension and gender may influence the number of MSCs reached after in vitro culture expansion.