Madrid researchers describe a new severe primary immunodeficiency

Madrid, 2011-September A group of researchers from the community of Madrid describes a new congenital immunodeficiency, which helps to understand the development and the role of T lymphocytes in a work published in the journal The Journal of Clinical Investigationwhich are those who coordinate the immune response of the organism. The study can help to improve the approach of other patients with severe congenital immunodeficiencies.

Immunodeficiency has been detected in two babies of different Ecuadorian families who were respiratory infections, diarrhea, delay in growth and low lymphocyte count. The work shows that there is a mutation not previously described in the gene that encodes the protein CD3delta, which is part of the receptor Antigen of lymphocyte T with which these cells identify pathogens to eliminate them.

The mutation affects cells “Tab” whose function is well known, but not the “diagnostic” believed to be a primitive but versatile t-lymphocyte type The work highlights the importance of studying the two types of cells as in the case of both babies, lymphocyte count was not so diminished in other serious immunodeficiencies, something that can confuse the diagnosis and delay unnecessarily the transplant.

Also describes a test for the rapid detection of mutation that allowed to diagnose the second case in less than a week. The new test, developed by Elena M. bust in Immunology at the Complutense University, may have application in prenatal diagnosis and genetic counseling to the families.

Institutional coordination

The study is the result of the coordination, within the Spanish group of primary immunodeficiencies (REDIP), Juana Gil, of the Immunology service at the Hospital Universitario Gregorio Marañón and Mª Jose Recio and Jose r. Regueiro, of the Department of Immunology of the Faculty of Medicine of the Complutense Universitywhere they are an expert group on pathophysiology of TCR/CD3.

The Group has counted on the collaboration of service of Immunology of the Hospital Universitario La Paz, where was diagnosed with one of the patients and children’s Hospital where transplantation was conducted and followed both children. At the Hospital Ramón y Cajal and the Centre for transfusion in the community of Madrid that conducted genetic studies, and the University of Freiburg in Germany have also worked.

“The discovery will improve the diagnosis and treatment of other patients with severe congenital immunodeficiencies and specialists serving them in Clinical Immunology, Pediatrics and Hematology services will help,” concludes Eduardo López Granados of Hospital La Paz, Center that coordinates ten years interhospitalarias of the Group of primary immunodeficiencies meetingsThanks to which began the collaboration for the study.

It might also be useful for public health in the region of Ecuador where they come from both families, which, despite not having close relationship, they share the same mutation and a common genetic origin, according to Miguel Angel Moreno Pelayo, the unit of Molecular Genetics at the Hospital Ramón y Cajal. Therefore authors will disseminate the findings among local pediatricians.