Bacteriophages isolated from dairy farm mitigated Klebsiella pneumoniae-induced inflammation in bovine mammary epithelial cells cultured in vitro.

Abstract

BACKGROUND:

Klebsiella pneumoniae, an environmental pathogen causing mastitis in dairy cattle, is often resistant to antibiotics. K. pneumoniae was used as the host bacteria to support bacteriophage replication; 2 bacteriophages, CM8-1 and SJT-2 were isolated and considered to have therapeutic potential. In the present study, we determined the ability of these 2 bacteriophages to mitigate cytotoxicity, pathomorphological changes, inflammatory responses and apoptosis induced by K. pneumoniae (bacteriophage to K. pneumoniae MOI 1:10) in bovine mammary epithelial cells (bMECs) cultured in vitro.

RESULTS:

Bacteriophages reduced bacterial adhesion and invasion and cytotoxicity (lactate dehydrogenase release). Morphological changes in bMECs, including swelling, shrinkage, necrosis and hematoxylin and eosin staining of cytoplasm, were apparent 4 to 8 h after infection with K. pneumoniae, but each bacteriophage significantly suppressed damage and decreased TNF-α and IL-1β concentrations. K. pneumoniae enhanced mRNA expression of TLR4, NF-κB, TNF-α, IL-1β, IL-6, IL-8, caspase-3, caspase-9 and cyt-c in bMECs and increased apoptosis of bMECs, although these effects were mitigated by treatment with either bacteriophage for 8 h.

CONCLUSIONS:

Bacteriophages CM8-1 and SJT-2 mitigated K. pneumoniae-induced inflammation in bMECs cultured in vitro. Therefore, the potential of these bacteriophages for treating mastitis in cows should be determined in clinical trials.

• Authors: Yuxiang Shi, Wenpeng Zhao, Gang Liu, Tariq Ali, Peng Chen, Yongxia Liu, John P Kastelic, Bo Han, Jian Gao
• Journal: BMC veterinary research (BMC Vet Res) Vol. 17 Issue 1 Pg. 37 (Jan 19 2021) ISSN: 1746-6148 [Electronic] England
• PMID: 33468111 (Publication Type: Journal Article)

Chemical References

• Cytokines
• L-Lactate Dehydrogenase

Topics

• Animals
• Apoptosis
• Bacteriophages
• Cattle
• Cell Line
• Cytokines (metabolism)
• Epithelial Cells (metabolism, microbiology)
• Female
• Inflammation
• Klebsiella pneumoniae (pathogenicity, virology)
• L-Lactate Dehydrogenase (metabolism)
• Mammary Glands, Animal (microbiology)
• Mastitis, Bovine (microbiology)