A common hormone has been found to be effective for rejuvenating the immune systems of mice as well as humans, according to a finding by scientists from the Monash University.

The scientists were led by Associate Professor Richard Boyd and Dr Jayne Sutherland from the Monash Immunology and Stem Cell Laboratories and revitalized the thymus - responsible for production of T cells, which are required for fighting against infection but which inhibit from early childhood.

From Monash.edu.au:

The Monash study showed inhibiting sex steroids through the Leuteinizing Hormone-Releasing Hormone could help regrow the thymus, increase output of new T cells, enhance T cell responses and improve recovery following bone marrow transplants. It also showed, for the first time, that prostate cancer patients who had their sex steroids temporarily blocked had increased levels of new T cells in their blood.

The researchers found inhibiting sex steroids improved the production of haemopoietic stem cells in bone marrow. These cells provide ‘fuel’ for the bone marrow and thymus to produce blood cells.

Associate Professor Boyd said the immune system deteriorated severely with age, and was further destroyed by severe viral infection and common cancer treatments such as chemotherapy and radiotherapy.

“The resulting immunodeficiency can allow cancer relapse and leave patients at greater risk of infections which are often fatal,” he said. “The ability to overcome these immune system deficiencies provides a completely new approach to treating cancer and may work in many other severe clinical conditions such as HIV/AIDS. It may also boost the effectiveness of vaccines to cancer and infections.”

This achievement appeared in an issue of the Journal of Immunology and is considered to provide a new hope to patients suffering from cancer, AIDS and other immunodeficiencies, and prove effective even for transplant patients.