Synthetic blood: The ultimate scientific achievement

Scientists have been trying to develop blood in laboratories for decades. Success however, has been limited. Blood has a very complex structure and therefore being able to replicate it has proven to be a gargantuan ask for the best brains around the world. Finally, two years ago, some success could be achieved.

Stem cells isolated from umbilical cord blood donated by pregnant mothers and from the blood of adult donors have been successfully manipulated in the laboratory so they develop into mature, functioning red blood cells, which normally transport oxygen from the lungs to the rest of the body. What the artificial blood researchers have been trying to cook up is not a true substitute, in that it wouldn’t perform all of the blood’s functions.

The need for artificial blood was felt when the phenomenon of trauma deaths were identified. Accidents, especially, see the highest number of trauma deaths due to lack of blood. Also, with the political scenario of the world swiftly moving towards a more violent phase, battlefield requirements were playing in the back of the scientists’ mind.

The biggest problem hindering progress till date was Hemoglobin, the protein in red blood cells that carries oxygen from the lungs to needy tissues. Hemoglobin can potentially damage tissue and cause blood vessels to constrict. That’s why hemoglobin is contained in cells to isolate it and its toxic iron. Any successful blood substitute would have needed to transport and deliver oxygen, while staving off the threat hemoglobin poses.

In past attempts, scientists have tried to tweak hemoglobin to make it safer. When that didn’t work out, they tried to engineer hemoglobin, and ended up encasing it in a synthetic polymer. They hope the case will ensure that their substitute blood, won’t cause a tightening in the blood vessels, which increases the risk of heart attack and stroke. Doctors think that this substitute would be ready for clinical use within the next two years.

The synthetic blood cells created is one-fifteenth the size of normal blood cells, however. This poses a danger of leakage. When a person goes into shock after blood loss, the blood vessels become even more prone to leaks. However, one advantage of the small size of the substitute blood is that it could be used for people with sickle cell disease. In sickle cell Anemia, the misshapen red blood cells clog up blood vessels, and it’s possible that synthetic blood could get around the logjams and deliver oxygen past those points.

Tests have shown that these manufactured red blood cells compare well to the ordinary red blood cells that are made in the body of healthy people. The revolution in blood may take some time. This current substitute has been tested in mice and is now in testing among larger animals.

There are many other hurdles that are coming to the fore as well. The researchers will eventually have to convince regulators that its product is safe enough to test in people. Several scientists have expressed concerns regarding the stance of authorities. They seem hesitant to green-light new trials of blood substitutes, and rightfully so because of safety concerns from past products. Plus, clinical trials of trauma-related treatments often run into ethical quandaries about informed consent.

Having said that, one can’t help but be cautiously optimistic about this product that can potentially change the face of medical science.