## 5 Conclusions  
During our experiments, the main goal was to investigate the potential effect of LPA species on the viability of hBM-dMSCs, in vitro. The experiments included the toxicity profile of various concentrations of 18:1, 18:2 and 16:0 LPA species alone or in combination with HSA to investigate if the addition of LPA is beneficial for the attachment, proliferation, and migration of hBM-dMSCs. The complex formation between HSA and LPA was also analyzed with the use of IR spectroscopy. With these experiments, we aimed to find out if there is any difference in the spectra of the formed complexes compared with the base materials that could be visualized with IR spectroscopy. Thus, the characteristic peaks were compared in order to determine if any shifting of the absorbance wavelength of the characteristic peaks occurs. We found small spectral shifts of the amide I and II bands of HSA in the presence of LPA, indicating subtle changes in the secondary structure of the HSA due to the binding of LPA. The effect of LPA was also evaluated in vitro, with the use of XTT and migration assay in hBM-dMSCs. We found that LPA enhances the viability of hBM-dMSCs alone, the effect of which is more pronounced when administered in combination with HSA. In summary, in the present study, we have demonstrated that LPA is suitable for increasing cell viability alone and in combination with HSA in vitro, which may be a useful supplementation in TERM-related applications.  
Conceptualization, A.M., I.H. and E.R.; methodology, A.M., I.H., J.P., A.H. and B.B.; investigation, A.M., I.H., J.P. and L.S.; data curation, A.M. and I.H.; writing--original draft preparation, A.M.; writing--review and editing, I.H., E.R.; visualization, A.M. and I.H.; supervision, I.H. and E.R.; funding acquisition, Z.B. and Z.L. All authors have read and agreed to the published version of the manuscript.  
Prepared with the professional support of the Doctoral Student Scholarship Program of the Co-operative Doctoral Program of the Ministry of Innovation and Technology financed from the National Research, Development and Innovation Fund, KDP-2020. This research was also funded by the Hungarian National Research, Development and Innovation Office, TKP2021-EGA-25, TKP2021-EGA-21, 2020-1.1.6-JOVO-2021-00010, 2020-1-1.6-JOVO-2021-00013, OTKA K-125174, PD-132851, K-135683, and K-139230 grants and by the Higher Education Institutional Excellence Program of the Ministry of Human Capacities in Hungary, within the framework of the Molecular Biology thematic program of the Semmelweis University, with support from the EFOP-3.6.3-VEKOP-16-2017-00009 grant. The Central Library of Semmelweis University also kindly provided funds for open access publication fees.  
The study was conducted according to the guidelines of the Declaration of Helsinki and approved by the Institutional Review Board of EUIG (29152-3/2019).  
Informed Consent Statement: Informed consent was obtained from all subjects involved in the study.  
The data presented in this study are available on request from the corresponding author.  
The authors are thankful to OrthoSera Medical Zrt., and the Department of Materials Science and Technology, University of Gyor for the research support.  
The authors declare no conflict of interest.