Platelets are critical for hemostasis, thrombosis, and inflammatory responses, but the events that leads to mature platelet production remains relatively unknown. For the longest time, it was believed by medical science that blood was produced from bone marrow. However, a recent study discovered that the lungs play a far more complex role in mammalian bodies than we thought, with new evidence revealing that they not only facilitate respiration, but also play a key role in blood production. 

Researchers made the discovery by two-photon intravital imaging. Experiments done on mice suggested that over half of the platelets produced in the mouse body came from the lungs, as reported by scientists from UC San Francisco.While the lungs have been known to produce a limited number of platelets as well as containing platelet-forming cells called megakaryocytes,  their role was thought to be little to none. Cells responsible for blood production are not restricted to just inside the bone marrow anymore.

Here, a process called hematopoiesis was thought to churn oxygen-laden red blood cells, infection-fighting white blood cells, and platelets – blood components required for the clotting that halts bleeding. But scientists have now observed megakaryocytes functioning from within the lung tissue to produce not a few, but most of the body's platelets.

Further studies also revealed a vast number of hidden blood stem cells as well as cells that create red blood cells sitting just outside the lung tissue. By their estimates, the lungs were producing at least half of the body’s blood supply.As to how these cells got to the lungs, the study suggests that the blood and platelet producing cells started out in the bone marrow and migrated to the lungs. Once at their new location, they started producing blood cognate to bone marrow.

The most profound hypothesis is that the lungs are the most oxygenated organs which creates favorable conditions for blood production. This study may lay ground for other similar studies, to unravel secondary roles of other organs, as nearly every organ has the capability for more than a single purpose.

The researchers say that their findings need to be replicated in humans first before they are sure that the same process occurs in humans. In addition, to understand how the marrow and the lungs work together as the body’s blood factory. In any case, this discovery could mean a great deal when it comes to treating blood-related illnesses.

COPYRIGHT: This article is property of We Speak Science, a nonprofit institution co-founded by Dr. Detina Zalli (Harvard University) and Dr. Argita Zalli (Imperial College London). The article is written by Vedat Sunguri ( Master of Pharmacy, University of Pristina) .