Human BioSystems Moves Forward With Advanced Donor Organ Preservation and Storage Technologies.

PALO ALTO, Calif. -- Human BioSystems, (OTCBB:HBSC) a biomedical research company primarily focused on creating preservation solutions for biological materials, is preparing to launch a comprehensive second-stage program to refine and validate their unique storage technologies for donor organs.

Dr. Luis Toledo, HBS Chief Medical Officer and an internationally recognized expert in the field of organ transplantation, remains exited about the groundbreaking discoveries made by HBS. "We feel we may have opened the doors to a revolutionary new science to preserve organs, including kidneys, hearts, lungs, livers and pancreas that could change the matching, availability and viability of transplants," Dr. Toledo said.

Dr. Toledo and HBS Senior Research Scientist, Dr. Fernando Lopez developed several proprietary methods of preserving donor organs for use in transplantation, in a series of pilot research studies. Some for relatively short-term organ storage, utilizes non-freezing refrigeration temperatures of 0 degrees C to 6 degrees C. Other alternative methods developed by HBS for long-term storage, utilizes sub-zero temperatures at about -20 degrees C and -80 degrees C.

Currently, most donor organs, such as kidneys, are perfused with an industry standard product known as the University of Wisconsin (UW) solution that has been used for about the last 20 years. Organs are immersed in UW solution and then packed on ice before storing for up to 36 hours. Hearts can generally be stored for a maximum of four hours using UW solution.

"There has been relatively little progress made in efforts to extend the preservation periods of organs during the past 15 years," Dr. Lopez stated. "The viability of the organs can dramatically change with every minute that goes beyond the recommended storage period. When this problem has occurred it usually causes cell damage and recovery periods for the recipient patient become longer and more dangerous."

Dr. Toledo noted that previous efforts to develop techniques for freezing organs have a history of failed endeavors since organ transplantation became a reality. "The primary reason that freezing donor organs at sub-zero temperatures hasn't worked is because the freezing process causes the water in the organ tissue to expand and build up razor-sharp crystals that destroy the cells," Dr. Toledo explained.

In order to create new and improved solutions and technologies, Dr. Toledo and Dr. Lopez carefully researched previous studies of their own as well as those published by others in the field. They compiled a list of compounds and ingredients that displayed promise of preventing damage observed in organs subjected to ischemia (where organs are deprived of oxygen) and reperfusion (the blockade of blood flow followed by its restoration).

Based on their research and findings they developed a unique solution with the following content and characteristics:

1. Protective Macromolecules
2. Supportive Amino-acids
3. Other Protective Compounds
4. Membrane Stabilizers
5. Krebs Cycle support
6. High Energy Compounds
7. Anti-inflammatory Compound

"We have evaluated more than 500 solutions and performed more than 350 rat kidney transplants before we achieved the optimum combinations of compounds and test results between June 2002 and June 2003," Dr. Lopez said.

Dr. Toledo and Dr. Lopez developed an experimental model for comparative short-term kidney preservation in which rat kidneys were stored in a refrigerator at approximately 2 degrees C to 4 degrees C for 36 hours and then, using a proprietary micro-surgical procedure, transplanted back into the rats. Remarkably, the transplanted kidneys regained their natural bright red color as blood flow was rapidly restored and were fully functional as urine production began immediately.

Using the traditional UW solution, transplant surgeons prefer to perform a transplant operation within 24 hours of preservation in order to avoid the cellular damage that can occur under ischemic conditions when cells are deprived of the oxygen required for metabolism. The HBS Solution and procedures yield extremely effective transplantations even after 40 hours of storage.

"In order to make accurate comparisons of the HBS Preservation Solution to other formulas on the market we created a patent-pending quality index that clearly defines four measurements of organ preservation success," Dr. Toledo said. "The Reperfusion Index, as we titled it, begins immediately after transplantation when the kidney has been anastomosed (vascular connected) and blood flow is allowed."

"In our experiments we found that organs preserved up to 40 hours with the HBS Solution maintained a very good viability and function and scored an overall average of 12 plus on the Reperfusion Index," Dr. Lopez said. "In contrast, donor kidneys perfused with the UW Solution and stored for 36 hours in the same refrigerated environment did not become a healthy bright red color with blood nor did the organs produce urine after transplantation."

In other research experiments conducted at the HBS Michigan research facility, Dr. Toledo and Dr. Lopez made a milestone discovery that may have a lasting impact on the manner in which donor organ storage and transplantation is practiced.

Historically when an animal, a human or an organ is frozen, by even just a few degrees below 0 degrees C, the water in the subject or organ expands and forms small ice crystals. As these crystals grow they cut through biological materials like razors. This phenomenon creates such irreparable damage to cells and tissue that organs stored in this manner could never be successfully transplanted.

The scientific staff at Human BioSystems headed by Dr. Toledo and Dr. Lopez has developed a proprietary solution that allows organs to be maintained at below-zero temperatures (down to -20 degrees C) without freezing.

"We developed a uniquely special mixture of several anti-freeze compounds that allowed us to reach 48 hours of preservation at -20 degrees C in a regular freezer without the formation of ice crystals," Dr. Toledo stated. "We observed initial good function of the kidneys after transplantation reflected in the normal urinary output. At the microscopic level we found good preservation of intracellular structures ((nuclei and membranes))."

Dr. Toledo went on to explain that he and Dr. Lopez conducted another series of experiments at -80 degrees C (cryo-freezing). "Amazingly we found that at such sub-zero temperatures using this high energy anti-freeze mixture our solution changed its physical structure and did not expand or cause damage to the organ," Dr. Toledo said. "After 12 hours of solid freezing we warmed the organs down to -20 degrees C and the solution became liquid once again."

"The organs were then transplanted into the recipients and we observed that all of the transplanted organs had initial function producing urine almost immediately," Dr. Lopez stated. "They also scored well on the Reperfusion Index that we created."

Dr. Lopez noted that some minor cell damage was present in the sub-zero frozen organs and that efforts are under way to analyze these findings and modify the technique to avoid such damage. "We are currently making improvements on our solution that will allow us to indefinitely suspend life in organs and make science fiction science reality," he exclaimed.

"We believe this technology will promote the development of several markets including organ banking," Dr. Toledo affirmed. "Other benefits will include the providing of time to make better donor organ matches with recipients. This will save lives and the enormous costs of anti-rejection drugs."

Human BioSystems is headquartered in Palo Alto, California.

Certain statements contained herein are "forward-looking" statements (as such term is defined in the Private Securities Litigation Reform Act of 1995). Because such statements include risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. Factors that could cause results to differ materially from those expressed or implied by such forward-looking statements include, but are not limited to, results from future research and testing, failure to obtain regulatory approval for the Company's products, if required, failure to develop a product based on the technology we have acquired, failure of any such products to compete effectively with existing products, failure to develop a cost effective commercial manufacturing method, the ability of the Company to fund additional studies and product development and other factors discussed in filings made by the Company with the Securities and Exchange Commission.

Human BioSystems (OTC Bulletin Board:HBSC)