Researchers at the University of Maryland announced on Apr. 28 that they have discovered a previously unknown pathway allowing immature red blood cells to import heme, a key component of hemoglobin, from surrounding cells during their final stages of maturation. The findings, published in Science, could have implications for treating genetic blood disorders such as beta thalassemia.
This research is significant because it challenges long-held assumptions about how red blood cells generate the large amounts of hemoglobin required to transport oxygen throughout the body. The study found that erythroblasts—immature red blood cells—can use a transporter protein called Heme Responsive Gene 1 (HRG1) to bring in heme after losing their own mitochondria. “We’ve shown that this transporter protein, HRG1, is essential for the production of healthy, mature red blood cells, particularly at a time when the body needs to produce red blood cells quickly due to certain stresses like being oxygen deprived at a high altitude or during blood loss,” said Iqbal Hamza, principal investigator and professor at University of Maryland College Park and School of Medicine.
The discovery has clinical relevance for iron deficiency anemia. “A common hallmark of anemia is pale, hemoglobin-deficient red blood cells,” Hamza said. “By identifying strategies to mitigate anemia, such as regulating heme delivery through HRG1 to enhance hemoglobin production, we could substantially reduce the morbidity and mortality associated with this condition.” The team’s experiments showed that mice lacking HRG1 were unable to increase their red cell production under stress and became anemic.
In addition to its research activities, the University of Maryland College of Agriculture and Natural Resources (AGNR) honors notable alumni through its Outstanding Alumni Awards program according to the official website. AGNR also relies on donations for faculty recruitment and scholarships while receiving funding through state-supported programs according to its official website. It engages communities across Maryland with educational initiatives benefiting families and farmers as reported by AGNR’s official site.
The college manages several research centers including facilities in Beltsville and Upper Marlboro used by faculty members according to AGNR’s website. Achievements within AGNR are recognized through various awards such as Excellence in Extension and Research Awards as stated by AGNR’s site. As part of Maryland’s land-grant system, AGNR collaborates with other institutions including University of Maryland Eastern Shore according to its official website.
Mark T. Gladwin, Dean at University of Maryland School of Medicine said: “This work reveals a previously unrecognized intercellular heme-transfer pathway that helps sustain red blood cell production under stress… Identifying HRG1 as a regulator of heme availability opens exciting therapeutic possibilities for conditions in which the body struggles to maintain healthy red cell production.”
Hamza said his future research will focus on understanding how heme is transported within individual cells and developing potential drug targets related to HRG1 expression.
