Nerve Growth Factor 1948 – A First Step Towards Cell Growth Factors

In an interview, Italian neurologist Rita Levi-Montalcini said that she was more of an artist, using intuition to guide her thinking about nervous system behaviour and the nerve growth factor (NGF) she discovered. After Italian fascist leader Benito Mussolini introduced a law restricting the academic employment of Jews, Levi-Montalcini had to conduct her research in a laboratory in her bedroom. Levi-Montalcini was the first Nobel laureate to die over the age of 100.

NGF is a small protein that plays a role in the growth and survival of certain neurons (nerve cells). 

In 1948, American scientist Elmer Bueker discovered that implanting a mouse tumour into the body wall of a chick embryo caused a large outgrowth of nerve fibres from the chick's sensory ganglia (masses of nerve cells). Levi-Montalcini and her colleagues later observed that a mouse tumour was invaded by the chick embryo's sensory and sympathetic nerve fibres. The sympathetic nervous system is part of the autonomic nervous system that prepares the body to respond especially to stressful situations. Sympathetic ganglia distant from the tumour were also seen to grow, proving that the tumour secreted NGF into the chick embryo's bloodstream. American biochemist Stanley Cohen and Levi-Montalcini also discovered that when antibodies were injected into newborn mice, the mice's sympathetic nervous systems did not develop properly.

Interestingly, NGF levels are higher when people first fall in love. 

NGF also increases survival times in mice after a heart attack and reduces movement disorders in mice with Parkinson's disease. In 1983, Levi-Montalcini and her colleagues established that NGF could affect nerves connected to the brain and spinal cord. 

Cohen also discovered epidermal growth factor (EGF), which triggers early eyelid opening and tooth eruption in newborn animals. 

Today, we know many factors that affect the differentiation and proliferation of various cell types in the human body.

Description of the article image: An image of a dorsal root ganglion (a mass of nerve cells) from a chick embryo after several hours of incubation in an NGF growth medium. The numerous projections extending from the ganglion are shown in pink.

Historical figures mentioned in the article: Elmer Daniel Bueker (1903–1996), Rita Levi-Montalcini (b. 1909), Stanley Cohen (b. 1922)

• Previous topic: Cortisone 1948 – The Miracle of Inflammation
• Next topic: Randomised Controlled Trials 1948 – More Reliable Results