Others are widespread and are not benign so far

Nature knows not the meaning of the word justice, it is concerned about equal opportunities in infectious agents. The effectiveness of the immune system is a striking example of this indifference to the disease. In France, one 5,000 children born each year with a serious immune deficit paralyzing army cell infantry responsible for ensuring the integrity of his body. But in reality, these deficiencies concern practically everyone, with varying degrees of severity. "We all have a hereditary immune deficiency, especially against infectious diseases." "It is more or less hidden by the action of the vaccines or antibiotics" explains Jean-Laurent Casanova, Immunology and Pediatric Hematology of hôpital Necker-Enfants service patients in Paris.

It was during major epidemics of the past such as plague or smallpox this truth came to light. Some miraculously passed through these plagues, while others fell and flies. "Until the early 20th century, average life expectancy was twenty-two years." "Nine times out of ten people died of infectious diseases", said Professor Patrick Berche, Dean of the Faculty of medicine René-Descartes in Paris. Recently, the Wyeth Foundation brought together some of the best French immunologists around a topic more than ever News: "we are not all equal before the infectious agents".

As a general rule, the immune system does its job. With a two-stage action (innate immunity and adaptive immunity), he successfully kills hackers trying to exploit the body: bacteria, viruses, pathogenic all kinds. "Hundreds of millions of people have been exposed to the avian influenza virus and only 127 patients have lost their lives ().". It may be the result of a particular provision of the H5N1 virus. "These patients were somehow predestined to die from bird flu," notes Patrick Berche.

Some of these serious failures are extremely rare and are only one in a million. Others are widespread and are not benign so far. This is the case of AIDS.

HIV savings a few highly exposed people (often prostitutes), while the majority of patients is contaminated during first contact. In almost all cases, the immune system is unable to control this retrovirus to the very unusual behavior (he tackles loaded cells to destroy). This information explains the difficulty encountered by researchers to develop a preventive or therapeutic vaccine. In fact, known currently no cases of spontaneous cure to infection with HIV. An investigation will soon start in the United States to determine the biological or genetic factors which give some people the ability to prevent the replication of HIV.

Commando operations

This biological troupe sentinels are dendritic cells. They isolate pathogens, cut into pieces, and then isolate a fragment they brandish their surface, such as the distinctive sign of the enemy. Recently, a team mixed Inserm/CNRS/Institut Curie has highlighted the conduct of these commando operations taking place every day in a healthy body. "If it treats the immune system to an army, it is very interesting to know how to make its soldiers" summarizes the Professor Alain Fisher, Hôpital Necker-children sick.

Injustice continues throughout life as confirmed by a survey of centenarians by an Institute of Boston. The State of health of nearly 800 people who have reached this venerable course was passed to screen, by a team of researchers.

According to the Coordinator of the work, Thomas Perls, these centenarians have an enormous advantage: their body is equipped with exceptional resistance to infectious diseases, immune system in concrete. Almost 40 of them have lived for more than twenty years with a chronic illness installed and "maintained under control" by the defences of their organization. Conclusion: more lives on, more is likely to remain (relatively) healthy. Before this result, American researchers have decided to launch an investigation more searched with a thousand of families whose members have of longevities out standards.

In addition to these lucky old genetic profile, it is planned to analyze their environment and their behavior (eating habits, hygiene of life). The objective of this work because there is doubt, find recipes for "aging in full form. An old dream with multiple keys are also located on genetics. Recently, a team from the University of Pittsburgh found in DNA of centenarians in healthy mental and physical, nine apparently responsible for parts of this good fortune. Curiously this coding is not the same for men and women.