Will it ever be possible to synthesize blood the way insulin is made?

Artificial blood will not be available any time soon, and the need for donations will remain acute for the foreseeable future.

Synthesizing blood is much more complex than synthesizing insulin. Blood includes many different kinds of cells, while insulin is a protein.

There are ways to make hemoglobin, the protein in blood that carries oxygen, and most of the blood alternatives or substitutes that are being worked on are hemoglobin molecules aggregated together. They will serve as a bridge for people who need transfusions.

However, the products that are being worked on would not be substitutes for transfused blood, except in emergencies or acute blood loss. Artificial blood cells are way off in the future, a decade or more.

Pigs’ blood, with minor modification of the surface of its cells, would be compatible in humans, but its use raises other issues, like disease transmission, that would have to be worked out.

Many products have been available for some time that serve many, but not all, of the functions of plasma, the liquid that carries the cells and proteins of blood. These products can be used in certain situations.