During her studies, she worked at the department of biochemistry and physiology under the supervision of Jean-Louis Prévost, and published her first research on internal secretions of the liver in 1902. In 1904 she defended her doctoral thesis on ureteric contractions and was awarded a university prize. Then, she became an assistant of Prevost and started her teaching career. In 1917, Stern was appointed professor of physiological chemistry and continued her original research, acquiring a considerable reputation in her field. She headed her department, established her own school of physiologists, and was also a consultant to pharmaceutical manufacturers. In Geneva, Stern worked together with Federico Battelli (1867-1941, Italian physiologist and biochemist, studied at Turin, emigrated for political reasons and worked in Geneva), Prevost’s successor, on oxidative metabolism, on respiratory enzymes, on the physiology of heart, blood, central and autonomous nervous systems. From 1918 to 1925 she conducted in collaboration with R. Gautier a series of experiments on tissue barriers and in 1921 she introduced the term “blood-brain barrier” at the Medical Society of Geneva. Stern continued this pioneering research studying the maturation of the hematoencephalic barrier in the developing brain. Because of her work, she came into close contact with the brain researchers Cécile and Oskar Vogt at the Kaiser Wilhelm Institute for Brain Research in Berlin. In 1924, Aleksei Nikolaevich Bach offered her to take the vacant position of head of the Department of Physiology at the Second Moscow State University. In March 1925, at the age of 48, the eminent scientist Lina Stern arrived in Moscow, where the physiology of Ivan Petrovič Pavlov was dominant. In the following four years she continued her research, published numerous articles in Russian, French and German journals, taught physiology and biochemistry, and tried to adjust to the new life and to the Soviet environment. From 1929 to 1948, she was the director of the new Institute of Physiology in Moscow and surrounded herself with a highly qualified research staff. In the following years, Stern invited the most eminent international scientists to visit her institute and many of them donated new equipment to her laboratories. She maintained contacts with her Western colleagues and attended  international conferences held abroad. She was engaged with a British colleague but the marriage never took place, because once married she was expected to interrupt her scientific career. She sacrificed her personal life, devoting entirely to science. In 1942, Lina Stern joined the Jewish Anti-Fascist Committee organized at the initiative of the Soviet Union in order to mobilize world Jewish support for the USSR’s war effort against Nazi Germany. At the end of World War II, Stalin changed his view and promoted antisemitism: this was the beginning of a series of actions against the members of the Committee. A moral and professional discrediting was directed to Stern. In 1948 she was expelled from all medicine and science positions and was also accused of “pseudo-teaching” and of “anti-Pavlovian” ideas. The main members of the Jewish Anti-Fascist Committee were arrested. Lina Stern was arrested on January 1949, at the age of 70, and remained in prison for almost four years, experiencing humiliation and physical strain. In 1952, the members of the Committee were tried in secret and, except for Stern, were executed. She was exiled in Dzhambul, Kazakhstan. In 1953, three months after Stalin’s death, Stern returned to Moscow. She regained her scientific status: she was still a member of the Academy of Sciences. She was allowed to establish a laboratory, at 76 years old, and headed it until her death.

Lina Solomonovna Stern died on March 7, 1968 and she was buried at the Novodevichij cemetery in Moscow.