Immunologic effects of probiotics and human health

Abstract

The human gastrointestinal tract (GIT) harbours an extremely complex and diverse microbial ecosystem representing over 500 different species. While a majority of indigenous bacteria are benign or beneficial, some possess the potential to cause disease; in healthy individuals, a balance exists between these populations. In addition to nutritional and barrier functions, the intestinal microflora plays an important role in guiding the development of a balanced immune system and maintaining gut homeostasis. Perturbations in the microbial homeostasis due to factors such as antibiotic therapy, stress and infection enhances predisposition to increased risk of infectious diseases, cancers and immunoinflammatory disorders.