Lina Solomonovna Stern or Shtern (Russian: Лина Соломоновна Штерн; 26 August 1878 – 7 March 1968) was a Soviet biochemist, physiologist and humanist whose medical discoveries saved thousands of lives at the fronts of World War II.

[1] Due to her Jewish background, it was very difficult for her to gain admission into Russian Universities, which is why she had to study abroad instead.

In 1912, Battelli and Stern, along with Torsten Thunberg, “discovered that minced animal tissues contain substances that can transfer hydrogen atoms from specific intracellular organic acids to methylene blue dye, reducing it to a colorless form.”[1] Their research was later on able to help Hans Krebs (biochemist) and his groundbreaking work on cellular respiration Due to her groundbreaking research and hard work, the University of Geneva allowed her to add Physiological Chemistry as an independent field of study to the curriculum of the medical faculty.

[1] It was from there that her research into the physiology of the central nervous system began – partly influenced by her friendship with Constantin von Monakow.

Initially, Giuseppe Pagano, Professor of Chemical Physiology at the Medical School of University of Palermo, started experimenting on animals to learn more about motor response and the cerebellum.

[1] On April 1, 1929, a new Institute of physiology was opened in the Academy of Sciences of the Soviet Union, and Stern became the director.

Soviet government decided to eradicate Jewish Anti-Fascist Committee (JAC) in the late 1940s as anti-Soviet organization.

[8] This barrier prevents most substances in the blood from entering the brain while allowing small molecules like oxygen and carbon dioxide to diffuse freely.

While working at the University of Geneva, Stern published a series of studies demonstrating the existence of the blood-brain barrier with colleague Raymond Gautier.

From these studies they were able to conclude that there exists a barrier between the blood and brain, which they termed in French "barrière hématoencéphalique".