Abstract 26: Influence of Blood Type in Umbilical Cord Blood Immune Cell Profile

Abstract Introduction Human immune system undergoes a remarkable journey from embryonic stages to infancy, marked by a gradual transition from reliance on innate immunity, which is genetically encoded, to the development of adaptive responses. Variations in immune cell numbers across different blood type (BT) can suggest a potential influence of ABO antigens on early immune cell composition. This interplay between genetic factors, maternal influence, and BT lays the foundation for lifelong immune health and disease susceptibility. ABO BT system, primarily known for its relevance in blood transfusions and organ transplants, has been the research subject exploring its associations with several diseases. As an early source of biological material, umbilical cord blood (UCB), it has been proven ideal for several diseases’ treatment, research, and diagnostic purposes. UCB also provides a pure sample for studying how genetic and maternal influences shape early immune system characteristics. Objectives This study focused on the relationship between BT and the immune system, aiming to understand the influence of BT on the number of nucleated cells, WBC, neutrophils, monocytes, lymphocytes, NRBC, and platelets from UCB samples. Methods It was used data from 910 cryopreserved UCB samples from BebéVida, a cryopreservation laboratory in Porto. To compare ABO groups, it was used the Kruskal-Wallis test. Statistically significance was considered for p-value <0.05. Results Results revealed significant increases in nucleated cells, WBC, NRBC, neutrophils, and monocytes in AB compared to A, and in O compared to AB. Regarding platelet, group A had more content than O group. Lymphocytes did not significantly differ between all BT tested. Discussion This study demonstrated the differences in immune system cells number between the different BT in UCB samples. This could be linked to A and B antigens presence/absence, however more research is needed to clarify. There are potential links between ABO blood groups and different diseases. This study demonstrated there is different patterns in the immune cells BT regarding UCB-BT, which could represent an important tool to help understand the onset of several diseases or predispositions. Elucidating these relationships, it can advance personalized medicine approaches and improve our understanding of disease predisposition across diverse populations.