Impact of microbial diversity on inflammatory cytokines and respiratory pattern measured in whole-body plethysmography in guinea pig models.

Objective: This study investigates the breathing patterns and immune status of guinea pigs raised under specific pathogen-free (SPF) conditions compared to conventionally bred (CON).

Methods: Breathing pattern parameters were assessed using whole-body plethysmography (WBP) during quiet breathing and saline nebulisation. Blood and bronchoalveolar lavage fluid (BALF) were analysed for white blood cell, neutrophil and eosinophil counts, and cytokine levels (TNF-α, IL-1β, IL-4).

Results: SPF guinea pigs exhibited higher tidal volume, expired volume, minute volume, and airflow parameters than CON guinea pigs. The immune analysis revealed lower white blood cell counts and IL-4 levels in SPF guinea pigs. These findings indicate that SPF guinea pigs have different respiratory and immune responses than CON guinea pigs.

Conclusion: The study highlights that the maturation processes affecting breathing pattern parameters in SPF guinea pigs differ significantly from those in CON guinea pigs. This suggests potential limitations of SPF animals in respiratory physiology research due to their different immune and respiratory responses.