Blood type theory is one of the fundamental bases for surgical operations. Only with this theory can safe transfusions occur, allowing many surgical procedures to proceed.
Li Ang took out the tools he had prepared in advance from the medical kit he carried with him—a large number of syringes, glass slides, glass test tubes, and the human-powered centrifuge he had previously used at the Duke Yan Mansion.
Li Ang drew a small amount of blood from himself, Yang Yu, Li Wei, Zhang Yuyan, and a few other classmates from the Academic Palace and placed it into glass test tubes, attaching labels.
Then, taking a small amount of fresh blood from each test tube, he combined them in pairs, dropping them onto glass slides for mutual mixing.
Under the watchful eyes of the Academic Palace Doctors and students, some blood samples began to clump together, while others merged smoothly.
To further verify his findings, Li Ang once again took a small amount of fresh blood from Dr. Su Feng and other volunteers for testing, yielding the same results.
"The donors come from all over the world and had no prior connections before coming to the Academic Palace, so claiming they have blood relations is a bit of a stretch. Therefore, the Blood Merging Method used in the Blood Test is also incorrect."
Li Ang said, "However, just proving this point is not enough. We must also understand why some blood can merge while others cannot. Where exactly is the problem?"
Li Ang used the human-powered centrifuge to extract half of all blood samples for separation.
After the blood coagulated, the top layer was a pale yellow, transparent liquid—the serum. The middle layer consisted of white solids—white blood cells and platelets—and the bottom layer was composed of red solids—red blood cells.
After separating the serum, Li Ang placed it into a new set of glass test tubes, labeled them, then mixed blood cells and serum in pairs, creating a chart based on the results.
"Do you all notice? After centrifugation, when a person’s own serum and blood turbidity—that is, their blood cells—are mixed, there is no reaction."
Li Ang continued, "But when the serum and blood turbidity of different people are mixed, sometimes there is a reaction, and sometimes there is not."
Dr. Su Feng curiously asked, "Why is that?"
"I believe the serum and blood turbidity each contain special substances. I call them antigens and antibodies," Li Ang explained. "When antigens and antibodies of the same kind meet, they counteract each other and react, much like fire meeting kindling. Different kinds of antigens and antibodies, however, do not react and can coexist peacefully. If a person’s blood turbidity contains A antigens, then their serum will not contain A antibodies, but B antibodies. If the blood turbidity contains B antigens, then their serum will not have B antibodies, but A antibodies. The former is A blood type, and the latter is B Blood Type."
"Wait, what about Li Wei’s blood?" Dr. Su Feng asked. "His blood turbidity won’t react with any serum, but his serum will react with other people’s blood turbidity."
"Correct. So, in Li Wei’s blood turbidity, there are neither A antigens nor B antigens. Accordingly, his serum contains both A antibodies and B antibodies. That is C blood type. Conversely, there are those whose blood turbidity contains both A and B antigens, but whose serum contains neither A nor B antibodies. That’s A-B blood type."
Li Ang jotted notes on the chart. "Speaking broadly, people can generally be divided into four blood types: Type A, Type B, Type A-B, and Type C. If Type A blood encounters Type B blood, their respective antigens and antibodies will react, causing all the blood to clot. When Type A blood meets Type A-B blood, the blood will clot halfway and merge halfway. Does this count as merging or not? Whereas in the Blood Test, as long as the blood types are the same, they will all blend together without any clotting, even without any blood relationship.
"To further validate this is quite simple: we just need to increase the sample size. If hundreds or thousands of people undergo blood typing, we will be able to figure it out."
Li Ang appeared calm and composed. He knew that once the blood type theory was promoted, it would inevitably be accepted as true. After all, no one wanted a stranger suddenly appearing, using archaic methods like the ’dripping blood on bones’ kinship test, to try and claim their inheritance. Therefore, the blood type theory had to be true, and could only be true.
Dr. Su Feng asked again, "Wait a minute. If there are four blood types, what would be the blood type of children born to parents with different blood types? If someone with Type A blood marries someone with Type B blood and they have Type A-B children, then over time, shouldn’t everyone in the world have Type A-B blood?"
"That’s why I’m thinking there might be randomness in the inheritance of blood types," Li Ang said. "If someone with Type A blood marries someone with Type B blood, they could have children with Type A, Type B, Type A-B, or Type C blood. If someone with Type A blood marries someone with Type C blood, they should also be able to have children with either Type A or Type C blood. These possibilities require further validation by increasing the sample size.
"However, one thing is certain: the Blood Test is completely erroneous and of no practical use. If this were treated as an absolute rule, who knows how many wrongful cases and personal tragedies would occur due to misjudgments in kinship."
Li Ang concluded this large-scale experiment, and Zhang Yuyan from the crowd showed her gratitude with a bow, while Yang Yu also expressed his thanks with a cupped hand gesture.
Let’s be thankful for Dr. Carl Landsteiner, who proposed the blood type theory, Li Ang thought, waving his hand at them to indicate there was no need for such formality.
With the noble cause of overthrowing the outdated Blood Test as a banner, combined with the Academic Palace Doctors’ thirst for knowledge, the development of blood type theory should advance quickly. For instance, two Type A parents might produce Type A or Type O offspring. Two Type A-B parents might produce Type A, Type B, or Type A-B offspring. This would conclusively discredit the Blood Test.
Next up is the practical application of blood type theory—transfusion, Li Ang mused. As long as we can overcome the common fear and ignorance regarding blood in Yu Country, we can legitimately use transfusions as an emergency medical procedure. Speaking of which, that Jing Monk from the Persian Hu Temple yesterday... whether he guessed it or genuinely knew something, his prediction of an impending bloody disaster was actually half right...
As he was pondering, a servant of the Academic Palace hastened over and said something to Li Wei.
Upon hearing the message, Li Wei’s expression changed dramatically, and he immediately ran over to Li Ang. "Risheng, the Eldest Son of the Cloud Banner General’s House has been injured in the family’s Martial Arts Arena and needs urgent medical attention. Could you please come with me?"
"Hmm? What happened?"
Li Ang asked for a brief leave of absence from Dr. Su Feng and hurriedly took his medical kit to follow Li Wei to the Academic Palace West Gate, where the Cloud Banner General’s carriage was already waiting.
After getting into the carriage, the servant from the General Mansion explained the situation. Cloud Banner General Chen Changxiao had had a son late in life, and the boy, studying the family’s martial arts since childhood, was nearing the age to take the entrance exam for the Academic Palace. Just moments before, Chen Changxiao had wanted to assess his son’s martial arts skills. During the practice, the boy accidentally fell from his horse and was wounded in the thigh by a Sword, causing unstoppable bleeding.
Li Ang reassured Li Wei. Cloud Banner General Chen Changxiao was Li Wei’s recommender. During the Academic Palace examination period, Li Wei had stayed at Chen Changxiao’s residence, and he and the Chen sons addressed each other as brothers.
However, for someone from the Chen family to rush to the Academic Palace for help... That Sword injury must be severe.