The Rh blood group antigen ccee stands for Rh-negative blood, also known as “panda blood”. The Rh blood grouping system has two types: positive and negative. Human red blood cells that contain the D antigen are Rh-positive, which is generally indicated by Rh (+); those that do not contain the D antigen are Rh-negative, which is generally indicated by Rh (-). And Rh blood group ccee has no D antigen, indicating that it is Rh-negative blood group. In China, more than 99% of the population with Rh blood type is positive, while Rh-negative blood type is extremely rare, so it is called “panda blood”. The Rh blood grouping system is of great clinical significance to clinical blood transfusion and obstetrics. If an Rh-negative patient is transfused with Rh-positive blood, hemolytic reactions are likely to occur, and in serious cases, may be life-threatening, so it is important to check and verify strictly before transfusion and make no mistakes.