Blood transfusions to pigs and monkeys Confirming the effect of heterogeneous blood transfusions on primates for the first time in the world

Sep 05, 2024

data photo source=Pixabay

For the first time in the world, a study has announced that blood from pigs has improved after transfusion into human-like primates. This study is expected to be the cornerstone of solving the blood shortage problem experienced around the world.

Recently, the decrease in blood donation has emerged as a big problem in the medical community. According to data from the Korean Red Cross, blood donation performance, which reached about 3.05 million in 2014, fell about 9% to 2.77 million in 2023. In addition, due to the aging and low birth rate, the number of people who can donate blood continues to decrease, and the imbalance in blood supply and demand is intensifying as the COVID-19 incident overlaps.

To solve these social problems, a research team led by Kang Hee-jung and Noh Joo-hye from the Department of Diagnostic Test Medicine at Hallym University's Sacred Heart Hospital (Hospital Director Kim Hyung-soo), Dr. Hwang Jung-ho from the Safety Evaluation Institute, and Optifarm (CEO Kim Hyun-il), a bio company, analyzed the effectiveness and safety of heterogeneous blood transfusions that administered pig red blood cells to non-human primates for the first time in the world. Pigs have recently attracted attention as a subject of xenotransplantation because physiological factors such as organ size and red blood cell function are similar to humans.

The research team manufactured blood from general experimental sterile pigs (WT) and transgenic pigs (triple gene removal, TKO) that are compatible with human blood as clinical red blood cell preparations, respectively. After that, 12 synomolgus monkeys with similar characteristics to humans were assigned to experimental group 1, experimental group 2, and control group 4 each, causing 25% blood loss (blood loss), and then transfused WT pig erythrocytes into experimental group 1 and TKO pig erythrocytes into experimental group 2. Then, before and immediately after bleeding, comparative monitoring was conducted with the control group injected with physiological saline instead of blood for 21 days after transfusion.

Results showed that hematologic indicators such as red blood cell count, hematocrit and hemoglobin levels improved by the first day after transfusion in all experimental groups, and TKO pig erythrocytes had less systemic side effects than WT pig erythrocytes. However, pig red blood cells transfused into the experimental group quickly disappeared from circulating blood after 24 hours, and side effects such as a strong antibody response were also observed.

Professor Noh Joo-hye explained that `pig erythrocyte transfusion can effectively increase hematologic indicators up to 24 hours after transfusion, but after that, it has been confirmed that its effect is limited by biological reactions.'

The research team demonstrated immediate hematologic benefits, but found that further pig genetic modification and immunosuppression studies that can evade biological responses are needed to maximize the effectiveness of heterologous blood transfusions.

Professor Kang Hee-jung, Director of Research, said "The results of this study provide important basic data for clinical application of heterologous blood transfusions"We will conduct follow-up studies to ensure that swine red blood cells can replace human red blood cells through the development of safer and more effective heterologous protocols and genetic modification."

As part of a national project conducted by the Civilian Military Cooperation Agency as a dedicated agency, the study was published in the June issue of the SCIE-level international academic journal Frontiers in Immunology (Impact Factor=5.7) under the title of 'Investigation of the effectiveness and safety of the wild-type and triple-gene knockout pig RBC transmissions in nonhuman primates).