Aim: 

Importance of the cytokines in materno-fetal immunotolerance has been studied by an evolutionary approach using different classes of vertebrates characterized by different reproductive modalities.

Methods: 

We carried out studies on the presence of the Interleukin-1 (IL-1) system, a major mediator of innate immune responses, in reproductive tissues of species with different reproductive strategies, i.e. viviparity, oviparity and ovuliparity.

Results: 

By immunohistochemistry and western blot analysis we showed expression of IL-1 system in the uterus/oviduct of species representing all three reproductive strategies. However, marked differences were observed between ovuliparous species and oviparous and viviparous ones.

Conclusion: 

These findings highlight the role of the innate immune response in the evolution of viviparity and suggest non-mammalian vertebrates as new animal models for studies of materno-fetal immunotolerance.