Appropriate clinical biopreservation of the hair follicle tissues is a critical factor in successful hair transplantation procedures. With modern hair transplant procedures often averaging between 6 and 8 hours to remove and relocate thousands of hair follicles – the process of preserving hair grafts while out of the body and with out the nurtients of the patients blood has become more critical. Since early 2013 Dr. Boden has been using Hypothermosol FRS as storage solution, instead of the usual normal saline for hair graft presevation during hair transplantation.
What is Hypothermosol
HypoThermosol hypothermic storage media is a novel, engineered, optimized hypothermic storage product of Biolife USA. This is designed to provide maximum storage stability for biologics at 2-8°C. This proprietary, optimized formulation mitigates temperature-induced molecular cell stress responses that occur during chilling and re-warming of cell and tissue intended for transplantation. HypoThermosol FRS includes components that scavenge free radicals, provide pH buffering, oncotic/osmotic support, energy substrates, and ionic concentrations that balance the intracellular state at low temperatures. It has proven much more effective in enhancing cell survival after transplantation as compared to other formulations. HypoThermosol meets USP Sterility and USP Endotoxin testing standards, and is manufactured under cGMP.
Cell Damage During A Hair Transplant Procedure
During the procedure, the follicle tissues experience multiple forms of stresses related to :
- before the donor strip and/or follicular units are extracted
- through the dissection and graft
- holding stages
Under normal conditions, the environment of human cells and tissues consists of an isotonic osmotic balance of ions that is maintained by ATP-driven cell membrane pumps. Major ionic constituents include sodium, potassium, calcium, magnesium, and chloride. The environment inside and outside the cell are distinctly different from one another, which subsequently regulate the passive ﬂow of water into and out of the cells. At the body temperature 37°C, the ﬂuid bathing the cells and tissues is isotonic. Nutrients flow through the membrane into the cells, while waste products and harmful free radicals are expunged from the cells. Only once these basic cell processes for maintaining “life” are in working order can the cell’s energies be directed to further functional cellular processes speciﬁc to that cell’s “job.”
When hair follicle tissues are removed from the body even for a short time, there are many potential detrimental consequences. Absence of nutrients such as glucose and oxygen renders the cells unable to generate fuel to maintain normal vitality
Hypothermic Biopreservation (primarily 2°-8°C) has been the preferred practical mechanism for storing cells, tissues, and organs for short periods of time. Most metabolic reactions will slow down approximately 50% for every 10°C decline in temperature from body temperature. This is the key to maintaining cells, tissues, and organs ( e.g. heart and kidney ) under adverse conditions. This has been widely used in preserving hair follicles for hair transplantation. Unfortunately hypothermia also introduces potential stresses which may eventually cause cell death, especially when when saline is used as a storage solution. Some hair transplant physicians may utilize other solutions such as Plasma-Lyte®, Lactated Ringer’s®, DMEM, or William’s E solution. Dr Limmer reported the steady decline in graft viability in correlation with graft storage time.
Hypothermosol vs Saline
It has been shown that in an enhanced stress model (prolonged storage out of the body) to highlight potential avenues for cellular preservation, grafts stored in saline for five days resulted in 0% survival, and grafts stored in HypoThermosol FRS demonstrated 44% survival. The strip/graft holding steps of the hair transplantation procedure are of critical importance to the success of the hair transplant. This comparison alone highlights the beneﬁts of using HypoThermosol to improved graft survival and maximize patient outcomes.
Storage of Hair Transplant Grafts outside of the body significantly impacts the quality of hair transplant procedures.
There are almost as many opinions on the best ex vivo storage media for follicle grafts during a hair transplant procedure as there are hair transplant surgeons.
Many surgeons have used the same protocol for years with great success, and there is always a tendency not to ‘rock the boat’ or mess with something that has worked in the past. But is your chosen hair graft storage solution as good as it could be? And how much impact does storage media have on the final quality of a transplant operation?
Which storage media offers the greatest protection to grafts during hair transplantation?
In a recent article for Hair Transplant International, renowned biopreservation expert Aby J. Mathew, Ph.D., argues that optimized intracellular-like solutions (such as HypoThermosol® FRS) are the best option for supporting grafts during ex vivo storage.
Dr. Mathew argues that these solutions offer the greatest level of protection and the lowest level of stress on the graft during its time outside of the body. This reduced stress increases the probability for improved survival and growth of follicular units post-transplantation, as can been seen in the image on the right.
How does an intracellular-like solution improve graft viability?
Most hair graft storage solutions in wide spread use represent ‘isotonic solutions’ composed of simple saline and modified cell culture media (Plasma-Lyte®, Lactated ringers®, DMEM, or Williams E), and were originally designed to support cells at normal body temperatures. Hair transplant grafts however are routinely stored in a hypothermic state (typically 2-8 °C) in order to reduce metabolic demand and gain the beneficial, protective effects of reduced temperature on the cells and tissues of the graft.
Unfortunately, the very same characteristics of hypothermia that confer graft protection also result in inactivation of the ATP-driven ion pumps that would normally maintain osmotic balance, leading to changes in cell membranes, instability of intracellular structures, free radical generation, abnormal water flux, and ultimately, cell death via apoptosis, necrosis, and/or secondary necrosis 8-21. These factors are all exacerbated in isotonic solutions that mimic the cells extracellular environment. While well suited to supporting an active cell at normal body temperature (where metabolic rates are normal and ATP-driven ion pumps are operational), isotonic solutions will actually accelerate the process of cell edema, lysis, and death under the hypothermic conditions experienced by hair grafts during ex vivo storage.
Maximizing the viability of hair transplant grafts following ex vivo storage.
To support a cell under hypothermic conditions and in order to reap maximum benefit from the stasis conferred by reduced temperature, we need a solution that maintains a balanced intracellular environment. An optimized intracellular-like solution (such as HypoThermosol® FRS) is formulated specifically to support tissue samples during hypothermic storage, and address the stresses of hypothermia with balanced ions and molecules, targeted pH buffering, and potent free radical scavengers that reduce hair follicle cell death via apoptosis and necrosis. Such a solution works to mitigate the overall cell stresses, buffering cells in each follicular unit, and increasing the potential for stronger and more rapid recovery of the graft post-transplantation.
The increased cell viability of tissue samples stored in an optimized intracellular-like solution versus those samples stored in a variety of isotonic solutions is clearly visible under fluorescent microscopy.
Enhancing the health and viability of the follicular unit grafts is essential to ensure the quality and success of a hair transplant procedure as measured by graft survival, hairline design, graft density, scalp irritation/edema, rate of regrowth, and hair shaft thickness. The optimization of ex vivo storage conditions is a practical and effective way to improve the health and viability of the follicular unit grafts.