Host-Pathogen Interactions of Mycoplasma mycoides in Caprine and Bovine Precision-Cut Lung Slices (PCLS) Models

Abstract

Respiratory infections caused by mycoplasma species in ruminants lead to considerable economic losses. Two important ruminant pathogens are Mycoplasma mycoides subsp. Mycoides (Mmm), the aetiological agent of contagious bovine pleuropneumonia and Mycoplasma mycoides subsp. capri (Mmc), which causes pneumonia, mastitis, arthritis, keratitis, and septicemia in goats. We established precision cut lung slices (PCLS) infection model for Mmm and Mmc to study host-pathogen interactions. We monitored infection over time using immunohistological analysis and electron microscopy. Moreover, infection burden was monitored by plating and quantitative real-time PCR. Results were compared with lungs from experimentally infected goats and cattle. Lungs from healthy goats and cattle were also included as controls. PCLS remained viable for up to two weeks. Both subspecies adhered to ciliated cells. However, the titer of Mmm in caprine PCLS decreased over time, indicating species specificity of Mmm. Mmc showed higher tropism to sub-bronchiolar tissue in caprine PCLS, which increased in a time-dependent manner. Moreover, Mmc was abundantly observed on pulmonary endothelial cells, indicating partially, how it causes systemic disease. Tissue destruction upon prolonged infection of slices was comparable to the in vivo samples. Therefore, PCLS represents a novel ex vivo model to study host-pathogen interaction in livestock mycoplasma.

Use of Precision-Cut Tissue Slices as a Translational Model to Study Host-Pathogen Interaction

“…Although PCTS have been used mainly to study viral infections, some studies have been performed with bacterial pathogens. These included so far work using Chlamydophila (Chlamydia) pneumoniae (3), E. coli (2), and Streptococcus (S.) suis ( 14), as well as M. mycoides capri strain GM12 and Mycoplasma mycoides mycoides strain Afadé, in bovine and caprine PCLS (19). In these studies, uninfected slices remained viable and without any significant morphological changes for a minimum of 2 weeks, as showed by a variety of techniques.…”

Contagious Bovine and Caprine Pleuropneumonia: a research community’s recommendations for the development of better vaccines

“…Therefore, such models are intrinsically more variable, require a large number of animals and are not the best option for the read out of immunological parameters over time. Moreover, recently established ex vivo models 61,62 for deciphering pathogenicity mechanisms and identifying virulence traits may prove beneficial (Table 1).…”

A Virulent Trueperella pyogenes Isolate, Which Causes Severe Bronchoconstriction in Porcine Precision-Cut Lung Slices

“…The use of precision-cut lung slices (PCLS) in threedimensional (3D) organ models is becoming an area of intensive research due to its close similarity to the host environment (6,7). There are many advantages in the use of PCLS, including isolated tracheal rings and bronchial rings, and the contraction of airway (7). PCLS have been commonly used in the study of viral infections (8), but there have been few studies on bacterial pathogens (9).…”