 Induced pluripotent stem cells obtained repogramming patients' cells, for example leukocytes, are a promising tool to study these pathologies and develop personalized therapies.X-linked agammaglobulinemia was one of the first described primary immunodeficiencies, discovered by Ogden Bruton in 1952.Primary immunodeficiencies were initially classified in 1970 by a committee of the World Health Organization.