William Henry Howell
1860-1945 · American · biochemistry
American physiologist at Johns Hopkins whose laboratory was responsible for the 1916 isolation of heparin and the subsequent characterization of its anticoagulant action, opening the modern anticoagulant-pharmacology era within which the molecular legacy of hirudin (Haycraft, 1884) was ultimately situated.
Profile
- Life years
- 1860-1945
- Nationality
- American
- Era
- early 20th
- Primary field
- biochemistry
Institutional Affiliations
- Johns Hopkins University (B.A., 1881; Ph.D. in Biology, 1884)
- Johns Hopkins University School of Medicine (Professor of Physiology, 1893-1931; Dean, 1899-1911)
- Johns Hopkins School of Hygiene and Public Health (founding co-Director with William H. Welch)
- National Academy of Sciences (member)
Key Contributions
- Served as Professor of Physiology and later Dean at the Johns Hopkins University School of Medicine (1893-1931), establishing one of the foremost American physiology laboratories of the early twentieth century.
- Directed the Johns Hopkins laboratory in which the second-year medical student Jay McLean, in 1916, identified the anticoagulant activity of a liver phospholipid preparation that Howell subsequently named heparin (1918).
- Continued the systematic characterization of heparin's anticoagulant action across the 1920s and 1930s, providing the laboratory groundwork for the eventual clinical development of heparin as a parenteral anticoagulant in the late 1930s and 1940s.
- Authored A Text-book of Physiology, a standard American medical-physiology reference across multiple editions in the early twentieth century, transmitting the emerging laboratory understanding of coagulation to a generation of American medical students.
- Established, through the Hopkins physiology laboratory, a sustained American scientific tradition of coagulation research that, by the late twentieth century, would converge with the molecular characterization of leech-derived anticoagulants (hirudin, antistasin) in a unified anticoagulant-pharmacology field.
Importance to Hirudotherapy
William Henry Howell's contribution to hirudotherapy is the parallel-historical role his laboratory played in opening the modern anticoagulant-pharmacology era within which the molecular legacy of leech-derived anticoagulants — and ultimately of hirudotherapy more broadly — would be ultimately situated. The 1884 isolation of hirudin from medicinal leech salivary glands by John Berry Haycraft at Edinburgh inaugurated the molecular era of hirudotherapy research. Thirty-two years later, in 1916, the medical student Jay McLean working under Howell's direction at Johns Hopkins isolated a second naturally-occurring anticoagulant principle — heparin — from mammalian liver. The parallel between Haycraft's leech-derived anticoagulant and Howell's mammalian-derived anticoagulant established the conceptual frame within which the field of anticoagulant pharmacology developed across the twentieth century. Howell's laboratory characterization of heparin across the 1920s and 1930s — including the 1925 American Journal of Physiology paper that established heparin as a defined biochemical anticoagulant principle — provided the experimental groundwork for the eventual late-1930s and 1940s clinical introduction of parenteral heparin as the first widely-used pharmaceutical anticoagulant. The clinical heparin era subsequently shaped the conceptual environment in which the late-twentieth-century pharmaceutical development of recombinant hirudin (lepirudin, desirudin) and of synthetic direct thrombin inhibitors (bivalirudin, argatroban, dabigatran) could be rationally pursued as alternatives or complements to heparin. The American Society of Hirudotherapy regards William Henry Howell as a foundational figure of the modern anticoagulant-pharmacology era within which the molecular legacy of hirudin is situated, and as the laboratory-historical counterpart to John Berry Haycraft's 1884 Edinburgh work. Howell's role within hirudotherapy is contextual rather than direct: he did not himself work on leech-derived anticoagulants, but the laboratory environment and pharmacological framework his work established made possible the eventual integration of hirudin-derived therapeutics into contemporary anticoagulant medicine.
Key Publications
- A Text-book of Physiology, for Medical Students and Physicians · Philadelphia: W. B. Saunders Company (multiple editions through 1940s) (1905)
- Two New Factors in Blood Coagulation — Heparin and Pro-Antithrombin · American Journal of Physiology (1918)
- Heparin, an Anticoagulant · American Journal of Physiology (1925)
External Resources
Influenced Research
Compounds and research areas tracing back to this figure's contributions:
Related Figures
John Berry Haycraft
1857-1922 · British (Scottish)
Edinburgh physiologist who discovered hirudin in 1884, founding the modern molecular pharmacology of leech saliva.
Karl Jacoby
1864-1926 · German
German pharmacologist who in 1902 produced the first crude hirudin powder, bridging Haycraft's discovery to industrial-scale anticoagulant chemistry.
Marie Termier
1859-1930 · French
French physician who in 1922 published one of the first formal clinical studies of leech therapy for post-surgical thrombosis, establishing modern clinical methodology in hirudotherapy.
Isabella P. Baskova
1936- · Russian (Soviet)
Moscow State University biochemist who in 1986 discovered destabilase — the leech enzyme that dissolves stabilized fibrin clots even when plasmin cannot.