Five Quarts_ A Personal and Natural History of Blood - Bill Hayes [53]
Of great immediate significance were his “pictures” of white blood cells. Though a predecessor, the British microscopist William Hewson (1739–1774), had discovered white blood cells a hundred years earlier, he had supplied only sketchy details. (Medical historians now explain that white cells had been overlooked for so long not only because they’re far outnumbered by red cells, which make up 45 percent of blood volume, with white just 1 percent, but also—for me, the more convincing reason—because they are almost transparent.) Hewson also correctly surmised that white cells serve an infection-fighting role, in concert with the lymphatic system. Confirming Hewson’s theory, another British William, physician William Addison, demonstrated in 1843 that blood collected from an injured person’s wound had far more white cells than blood taken from elsewhere in that person’s body. Clearly, white cells were converging, but for exactly what purpose? Subsequent scientists, leading up to Ehrlich’s generation, discerned that white cells were, indeed, the army of the blood—helping defend the body against bacteria, fungi, and viruses. But it was Paul Ehrlich who first identified its main soldiers. By using his technique of selective staining, he differentiated the two broad classes of white cells, leukocytes and lymphocytes, and discovered three of the five specific types of white cells now known. He found he could illuminate each of these three using a different kind of dye. The names Ehrlich gave the cells were mini tributes to the dyes themselves: the eosinophil, which stained red from the eosin dye; the basophil, blue from a base dye; and the neutrophil, a pinkish color from a neutral dye.
Ehrlich’s heat-fixed blood-staining technique soon became standard practice, helping to usher the science of hematology into the modern age. Adopting his methodology, other scientists joined Ehrlich in making finer and finer distinctions about the behavior and function of both red and white blood cells, particularly in diseases such as anemia (characterized by a lack of hemoglobin) and leukemia (an overabundance of white cells). Likewise, quantitative blood counts were now possible and allowed for quick, accurate diagnoses of life-threatening conditions. The modern-day routine blood test called a CBC (complete blood count) is a direct descendant of Ehrlich’s innovation.
For his accomplishments, Ehrlich is now often lauded as the “father of hematology,” a fact that calls for a small digression. Medical historians, I’ve noticed, demonstrate an almost comical penchant for assigning paternity to branches of science even if the field is already well populated with fathers. In my studies, Ehrlich is the fifth father of hematology I’ve come across, but this in no way minimizes his contribution. Among these patriarchs, though, Ehrlich stood out in one respect: He didn’t dote. While it is not unusual for a scientist to devote his or her life’s work to one specialty, Ehrlich tended to make discoveries and then, as I see it, abruptly move on. But he described it with greater eloquence: “One must not stay in a field of work until the crops are completely brought in, but leave still some part of the harvest for the others.” He moved on, again and again, to great success. Historians, in fact, also remember him as the father of histology, immunology, experimental oncology, and the aforementioned chemotherapy and cytochemistry.
Not all of Paul Ehrlich’s pursuits were academic, however. Five years into his tenure at the Charité Hospital, the then twenty-nine-year-old confronted a malady for which a cure is not always welcomed: lovesickness. The object of his infatuation was Hedwig Pinkus, a petite beauty ten years younger than him, the daughter of a prominent family from his hometown of Silesia. Though he squeezed