Cesarean section induced dysbiosis promotes a type 2 biased immune response, but has no effects on oxazolone-induced dermatitis in mice

Delivery by cesarean section is associated with an altered gut microbiota colonization and a higher risk of developing chronic inflammatory diseases later in life. However, results from epidemiological studies investigating the effect of CS delivery on development of atopic dermatitis are contradictive and often biased by confounding factors. The aim of this study was therefore to provide experimental evidence for a possible link between CS and allergy in a mouse model for atopic dermatitis. It was hypothesized that mice delivered by CS, and human CS GM transplanted mice develop severe dermatitis due to dysbiosis early in life.Conventional BALBc mice delivered either by CS or vaginal delivery and mice transplanted with GM from CS or VD donors were challenged with oxazolone at 8 weeks of age to mimic atopic dermatitis. The severity of dermatitis was evaluated by ear thickness, clinical and histopathological assessment of the ear. The immune response was assessed by serum IgE concentration, cytokine production in the inflamed ear,and the presence of immune cells in the draining lymph node.. The results showed that both CS delivered mice and mice inoculated with human CS-GM had a higher IgE concentration, and a higher proportion of Th2 cells was found in the CS GM inoculated mice. However, CS delivery or CS GM transplant had no effect on of the degree of dermatitis. In conclusion, CS associated GM enhances a Th2 biased immune response, but had no effect on oxazolone induced dermatitis in mice.