Medicines manufactured in space

Medicines manufactured in space
Medicines manufactured in space

Any attempt to shape the world and modify human personality in order to create a self-chosen pattern of life involves many unknown consequences. Human destiny is bound to remain a gamble, because at some unpredictable time and in some unforeseeable manner nature will strike back.

Mirage of Health, Rend Dubos

Whenever the subject of space Whenever the subject of space industry is mentioned, a few prejudices automatically arise in most peoples minds. This is true even of those of us who have been interested in space technology for the last four decades. We conjure up visions of huge solar power satellites beaming electricity to an energy starved earth and space factories producing new materials, superior crystals and sophisticated alloys that cannot be made in earth’s gravity field. However, the most important products of space industry, the ones that will most affect our everyday lives, will probably be in the biological and pharmaceutical fields.

It is felt that science which has eradicated diseases like smallpox from earth will continue that work in space because the weightless­ness and high vacuum in orbit offer unique advantages to bio­technology. Medicines from space are so fraught with promise that a hundred years hence, mankind may look back on the early space age less as the era in which we explored the solar system or developed any other technology and more as the time when both disease and death were conquered by scientists working in orbiting bio­laboratories.

One increasingly important field is cell biology. Hormones, enzymes, antibodies and other medically useful materials are manufactured by using cell cultures. But getting the living cell to grow in vitro rather than in vivo poses enormous problems for scientists. Because of this, many processes that theoretically could be carried out by cultured cells remain impracticable.

It is expected that all these may soon change. Biologists believe that many of the things they cannot do here on the ground, can be accomplished in the weightlessness of space. This is particularly true for cell biologists.

Growing mammalian cells—often the most useful—is especially difficult. Mammalian cells like to attach themselves to something before they will do anything, even carry on their normal metabolism. Without a supporting surface, cells will rarely produce the valuable products biotechnologists are looking for.

Culturing mammalian cells, therefore, required cleverly designed culture banks with many layered membranes to which the cells can attach themselves. Nutrients and other raw materials must then be pumped past the cells on these membranes.

The problem is that cells rarely attach themselves to such membranes in neat layers only one cell thick. Instead, they pile atop one another, the upper cells smothering the ones beneath.

One recent solution to this problem is the microbead, a plastic sphere often less than a millionth of an inch in diameter. A single mammalian cell can attach itself to each microbead and be quite happy and productive.

And yet this does not solve the problem either. When the cells attach themselves to the beads, they sink to the bottom of the culture bank, again forming a sediment many cells thick. Cells on top get all the food while those at the bottom end up with little of the nutrient solution. Metabolic wastes build up in the stagnant layer and even the gluttons atop are eventually killed by the poisons accumulating underneath.

The only way to keep this from happening is to stir the culture. But a whirling stirrer can deal the fragile cells a death blow. At best a battered cell stops cooperating with the biotechnologists.

But in the weightlessness of orbit, the cells in their microbeads cannot settle to the bottom of the container; there is no bottom. Without gravity, the cells will remain suspended in their cultured medium. Then they can be put to work making the hormones,

enzymes and other cell culture products needed by the sick and injured back on earth.

Weightlessness also permits the use of biotechniques that are difficult and, sometimes, impossible on earth. One process known as continuous-flow electrophoresis is a means of separating molecules from a solution by using an electrical field. If it could be made practical, it would be extremely useful in preparing hard to purify medications.

Under earth’s gravity, the continuous-flow electrophoresis is difficult to maintain. The electrical field heats the cells and their culture medium, and convection current in the fluid remixes the compounds one is trying to separate. Convection is the effect of gravity- in weightlessness there is no convection to defeat the separation.

It is felt in scientific circles that the process of separating biological materials in space using continuous-flow electrophoresis has a high probability of producing of human or animal diseases. These sub­stances are currently not being produced in sufficient quantities or purity in ground-based facilities.

When a spacecraft involved in such a project begins its flights into earth s orbit, one must perhaps not view it as an expensive toy that permits some scientists to engage in their favourite hobbies. On the contrary, we must look at it with the knowledge that what is learned in its cargo bay and what it carries back from orbiting laboratories may save human lives.

Scientists are, therefore, very optimistic about the success of such programmes. If they can foresee conditions that have the potential of producing pharmaceuticals from experiments based in space without ever having been actually in orbit to experiment with biological process, one can imagine the explosion of knowledge and technique, once people are routinely able to travel and live in space for months at a time. They would be justified in claiming that we will soon be experiencing the dawn of a new era in biotechnology.


Please enter your comment!
Please enter your name here