The antigen leukocyte antibody test is one that claims to measure adverse reactions to dietary substances. It was created by American Medical Testing Laboratories and is now marketed by Cell Science Systems of Deerfield Beach, Florida. Researched conducted at Yale School of Medicine published in BMJ Open Gastroenterology in 2017 demonstrated improvement for those with irritable bowel syndrome"These findings reject the null hypothesis and show that a diet guided by leucocyte activation testing results in demonstrable clinical improvement in IBS. These clinical results, associated with a reduction in plasma neutrophil elastase, have implications for better understanding the role of food intolerance and the pathophysiology of IBS."