Effects of Cryopreservation on Cell Viability and Insulin Secretion in a Model Tissue-Engineered Pancreatic Substitute (TEPS)

The use of encapsulated insulin-secreting cells constitutes a promising approach towards the treatment of insulin-dependent diabetes. However, long- term storage for off-the-shelf availability still remains an issue, which can be addressed by cryopreservation. This study investigated cryopreservation of a model tissue-engineered pancreatic substitute by two ice-free cryopreservation (vitrification) solutions (designated VS55 and PEG400) in comparison to a conventional freezing protocol. The model substitute consisted of insulin-secreting mouse insulinoma βTC3 cells entrapped in calcium alginate/poly-L-lysine/alginate (APA) beads. Cell viability and static insulin secretion from the thawed cryopreserved groups were characterized and compared against fresh controls. Cell viability tests using alamarBlue® showed that, compared to the fresh groups, the VS55 had the highest viability (p < 0.05), followed by both the PEG400 (p < 0.001) and the frozen groups (p < 0.001). In response to a square wave of glucose, the static insulin secretion data showed that the VS55 and PEG400 groups had similar induction levels against the fresh group, whereas the frozen group had the poorest secretion rate. Cryosubstitution of capsules showed ice formation in the frozen group but no ice in the vitrified groups. Microscopic observations revealed holes and/or tears within beads subjected to freezing, whereas no such abnormalities were detected in the vitrified samples. Overall, vitrification was found to be a promising preservation procedure for this encapsulated cell system.

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Does Stored Hpc, Apheresis Product Need an Expiration Date? Graft Cell Viability After Long Term Storage

Biology of Blood and Marrow Transplantation ◽

10.1016/j.bbmt.2010.12.203 ◽

2011 ◽

Vol 17 (2) ◽

pp. S220

Author(s):

M. Merchant ◽

W. Huang ◽

M. Olszewski ◽

M. Kletzel

Keyword(s):

Cell Viability ◽

Expiration Date ◽

Long Term Storage ◽

Term Storage

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Long-term storage in liquid nitrogen does not affect cell viability in cardiac valve allografts

Cryobiology ◽

10.1016/j.cryobiol.2008.07.008 ◽

2008 ◽

Vol 57 (2) ◽

pp. 113-121 ◽

Cited By ~ 21

Author(s):

V. Mirabet ◽

C. Carda ◽

P. Solves ◽

E. Novella-Maestre ◽

F. Carbonell-Uberos ◽

...

Keyword(s):

Cell Viability ◽

Liquid Nitrogen ◽

Cardiac Valve ◽

Long Term Storage ◽

Affect Cell Viability ◽

Term Storage

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Enhanced Cellular Cryopreservation by Biopolymer-Associated Suppression of RhoA/ROCK Signaling Pathway

Materials ◽

10.3390/ma14206056 ◽

2021 ◽

Vol 14 (20) ◽

pp. 6056

Author(s):

Tae Wook Lee ◽

Gyeong Won Lee ◽

Seonyeong An ◽

Keum-Yong Seong ◽

Jong Soo Lee ◽

...

Keyword(s):

Cell Viability ◽

Signaling Pathway ◽

Freezing Process ◽

Cryogenic Temperatures ◽

Ice Crystal ◽

New Approach ◽

Long Term Storage ◽

Hyaluronic Acids ◽

Term Storage

With increasing demands on long-term storage of cells, cryopreservation of cells is gaining more importance in cell-based research and applications. Dimethyl sulfoxide (DMSO) is a commonly used chemical cryoprotectant, providing increased cell survival during the freezing process. However, its use is limited in clinical applications due to its low biocompatibility above cryogenic temperatures. Herein, we present a new approach for reducing the use of DMSO in cryopreservation by using biodegradable hyaluronic acids (HAs). By adding HAs into cryoprotectant media containing a low concentration of DMSO, higher cell viability and cell proliferation rate were observed upon thawing after cryopreservation. The HA-supplemented cryopreservation media did not reduce the size of the ice crystal, which significantly influenced cell viability during cell freezing, but decreased the Ras homolog family member A (RhoA)/Rho-associated protein kinase (ROCK) signaling pathway related to apoptosis. The cell-interactive cryoprotectants containing HA can be applied to the development of a new cryoprotectant that reduces the adverse effect of DMSO.

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Novel Approaches to the Cryopreservation of Human Spermatozoa: History and Development of the Spermatozoa Vitrification Technology

Journal of Reproductive and Stem Cell Biotechnology ◽

10.1177/205891581100200207 ◽

2011 ◽

Vol 2 (2) ◽

pp. 128-145 ◽

Cited By ~ 5

Author(s):

Evgenia Isachenko ◽

Gohar Rahimi ◽

Peter Mallmann ◽

Raul Sanchez ◽

Vladimir Isachenko

Keyword(s):

Ice Crystals ◽

Intracellular Lipids ◽

Cryoprotective Agents ◽

Long Term Storage ◽

Cryopreservation Techniques ◽

Water Quality And Quantity ◽

And Storage ◽

Term Storage ◽

Conventional Freezing

Cryobiology is very intensively applied in reproductive and veterinary medicine for preservation of gametes, embryos and reproductive tissues. Sub-zero temperatures combined with appropriate cryoprotective agents preserve the physiological and reproductive functions of the cells making long-term storage possible without loss of viability. With the use of cryoprotective agents it has become possible to develop cryopreservation techniques, such as the slow conventional freezing and vitrification that are in use in the present times. In slow controlled-rate conventional freezing extracellular ice crystals are formed whereas in vitrification no ice crystals are formed. Glass formation is compatible with the survival of the cell and the preservation of its intracellular structures provided the type(s) and concentrations of cryoprotectant used are not chemo- or osmotoxic. However, irrespective of the type of cooling method employed the cryosurvival of cells and tissues is influenced by the size and maturity of cells, amounts of intracellular water, quality and quantity of intracellular lipids, type of cells, their function and morphology. The intracellular milieu of cryopreserved cells and tissues remain less understood. The application of nanotechnology may help reveal and help advance our knowledge of the cryobiological principles involved in cryosurvival. At this moment the methods of cryopreservation that merit further investigation are vitrification and lyophilization. Vitrification is cheap if reagents are prepared in-house and the procedure can be performed rapidly. It has been successfully applied for gametes and embryos (of different stages of development), and reproductive cells/tissues, somatic cells and stem cells. However, vitrification is more demanding technically and requires operation and storage at sub-zero temperatures. On the other hand lyophilization deserves further investigation because it is a cheaper form of cryopreservation that may enable cryostorage at less demanding temperatures of 4°C and may even allow transport at ambient temperature. These possibilities are explored in this review.

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Modelling of Moisture Movement in Wood during Outdoor Storage

Nonlinear Analysis Modelling and Control ◽

10.15388/na.2001.6.1.15210 ◽

2001 ◽

Vol 6 (2) ◽

pp. 3-14 ◽

Cited By ~ 23

Author(s):

R. Baronas ◽

F. Ivanauskas ◽

I. Juodeikienė ◽

A. Kajalavičius

Keyword(s):

Experimental Data ◽

Finite Difference ◽

Climatic Conditions ◽

Two Dimensional ◽

Moisture Movement ◽

Finite Difference Technique ◽

Long Term Storage ◽

Space Formulation ◽

Term Storage

A model of moisture movement in wood is presented in this paper in a two-dimensional-in-space formulation. The finite-difference technique has been used in order to obtain the solution of the problem. The model was applied to predict the moisture content in sawn boards from pine during long term storage under outdoor climatic conditions. The satisfactory agreement between the numerical solution and experimental data was obtained.

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