Class II obese and healthy pregnant controls exhibit indistinguishable pro‐ and anti‐inflammatory immune responses to Caesarian section

INTRODUCTION: Obesity during pregnancy is associated with meta‐inflammation and an increased likelihood of clinical complications. Surgery results in intense, acute inflammatory responses in any individual. Because obese individuals exhibit constitutive inflammatory responses and high rates of Caesarian section, it is important to understand the impact of surgery in such populations. Whether more pronounced pro‐inflammatory cytokine responses and/or counterbalancing changes in anti‐inflammatory immune modulators occurs is unknown. Here we investigated innate immune capacity in vivo and in vitro in non‐obese, term‐pregnant controls versus healthy, term‐pregnant obese women (Class II, BMI 35–40). METHODS: Systemic in vivo induction of eleven pro‐ and anti‐inflammatory biomarkers and acute phase proteins was assessed in plasma immediately prior to and again following Caesarian section surgery. Independently, innate immune capacity was examined by stimulating freshly isolated PBMC in vitro with a panel of defined PRR‐ligands for TLR4, TLR8, TLR3, and RLR 24 h post‐surgery. RESULTS: The kinetics and magnitude of the in vivo inflammatory responses examined were indistinguishable in the two populations across the broad range of biomarkers examined, despite the fact that obese women had higher baseline inflammatory status. Deliberate in vitro stimulation with a range of PRR ligands also elicited pro‐ and anti‐inflammatory cytokine responses that were indistinguishable between control and obese mothers. CONCLUSIONS: Acute in vivo innate immune responses to C‐section, as well as subsequent in vitro stimulation with a panel of microbial mimics, are not detectably altered in Class II obese women. The data argue that while Class II obesity is undesirable, it has minimal impact on the in vivo inflammatory response, or innate immunomodulatory capacity, in women selecting C‐section.