Introduction: The polyvinyl alcohol (PVA) is a polymer of great interest because of their desirable characteristics specifically for various pharmaceutical and biomedical applications i.e. tissue implants. For this, the cells must remain intact and housed within the material and having sufficient permeability to let the exchange of various substances. PVA is a hydrogel that allows the diffusion of substances through the pores, which are caused by the physical crosslinking of the polymer after several freezing/ thawing cycles. However to hold the greatest number of cells within the scaffold, it is necessary to remove the water contained in the pores of the biomaterial. Therefore, the scaffold was subjected to a controlled dehydration process, some weight lost was recorded due to the decreased amount of water but its structure was not modified, and throughout the process a sterility protocol was conducted. To keep the cell survival within the scaffold, the size and porosity distribution were controlled to allow enough permeability to achieve the exchange of various biochemical substances.
Materials and Methods: We constructed PVA scaffold using two molecular weights Mw = 85 000 to 146 000 of 95% degree hydrolysis and two concentrations weight 5% and 7% by physical method of several freezing/ thawing cycles; obtaining a size and distribution of porosity ranging from 25 nm to 100 μm. The cell lines used for this trial were the SUB-15 derived from acute lymphoblastic leukemia and MM.1R cell line derived from a multiple myeloma. The scaffold was subjected to 7 cycles of dehydration, losing weight but maintaining its structure. It was concluded that in the fourth cycle, the scaffold has the best conditions to host the greatest amount of cells which receive enough nutrients for their survival.
Results: The scaffold derived from PVA with dehydration cycles was able to maintain the cells inside; the nutrients permeate through its pores and maintain the survival of 95% of the cells under controlled cultivation. The cells proliferated and did not change their morphology.
Discussion: The main issue for transplantes, is that cells must remain inside the material avoiding incompatibility of tissues and immune system involvement. PVA is a biocompatible material that protects cells of the immune system entirely, this being an extremely important factor in clinical applications. The scaffold guarantees the interaction among cell and nutrient migration derived from the cell lines SUB-15 and MM.1R.
Conclusions: These results demonstrate that building a biocompatible scaffold that interacts with cells and keep them in optimal conditions is of great importance, as it could be used for multiple applications in clinical, mainly in the transplants.
Dirección de Investigación del Hospital General de Mexico "Dr. Eduardo Liceaga" (N° project: DI/14/204/03/057); Conacyt (N° project: 206574)
References:
[1] R. M. Quispe-Siccha, B. Reyes-Ramírez, C. García-Segundo, N. Hevia-Montiel, F. Arámbula-Cosío, R. Sato-Berrú, J. O. Flores-Flores. Journal of Applied Research and Technology, Vol. 10 No.1, pp. 63-71, 2012