Innate immunity represents a current research trend in a wide spectrum of medical fields. Paediatric gastroenterological pathologies are amongst the most common in daily practice. The relationship between these two is not currently fully understood, but multiple researchers worldwide have emphasised the important contribution of innate immunity in the etiology of different gastroenterological disorders, such as gastritis, celiac disease, or inflammatory bowel disease, whose onset is usually during childhood or adolescence.

The existence of a relationship between innate immunity mechanisms (e.g. toll-like receptors) and the onset of certain gastroenterological pathologies is undoubtable, but a more thorough approach in this topic would be extremely useful to understand clearly the mechanistic pathways and to create a solid basis for potential prevention or treatment strategies. Innate immunity responses are involved in the development of both gastroenterological infectious disorders, such Helicobacter pylori-induced gastritis, and autoimmune disorders, such as celiac disease or inflammatory bowel disorders. Nevertheless, it remains to be seen whether these responses depend only on the individual’s susceptibility or whether they might be externally influenced. A complex and integrative mechanistic model of the relationship between innate immunity and multiple gastrointestinal tract pathologies would be extremely useful for opening multiple research directions. Moreover, paediatric populations are ideal for studying this topic not only because these pathologies usually occur in children, but also due to the optimal time of prevention and intervention in order to reduce the occurrence of further complications. Taking into account the associated life-threatening complications of these pathologies during childhood, a proper elucidation of these mechanisms might represent the cornerstone for decreasing both morbidity and mortality related to them. Another current challenge of the medical and research field is to define the role of gastrointestinal microbiota in the area of paediatric gastroenterology. Moreover, it has been found that the maternal microbiota might be involved in shaping postnatal immunity. Postnatal immunity responses seem to be influenced by other environmental factors including gastrointestinal microbiota. Innate immunity also seems to be involved in other maternal and gestational concerns with a great impact on birth outcomes.

The main aim of this Special Issue is to define an integrative mechanistic model for a clearer understanding of the relationship between innate immunity and paediatric gastroenterological diseases, along with other factors, such as maternal microbiota or gestational pathologies. Original research and review articles are welcome.

Potential topics include but are not limited to the following:

• The role of innate immunity in the onset of celiac disease
• Paediatric gastritis and innate immunity
• Innate immunity, Helicobacter pylori infection, and gastric microbiota
• Innate immunity and childhood obesity
• Innate immunity and inflammatory bowel disease
• Innate immunity and cow's milk protein allergy
• Innate immunity and paediatric hepatitis
• Immunity, inflammation, and fetal outcomes
• Gastric carcinogenesis and innate immunity
• Bowel carcinogenesis and innate immunity
• Innate immunity and infectious diarrhoea