Type VI Secretion System Accessory Protein TagAB-5 Promotes Burkholderia pseudomallei Pathogenicity in Human Microglia
Issued Date
2023-11-01
Resource Type
eISSN
22279059
Scopus ID
2-s2.0-85178142336
Journal Title
Biomedicines
Volume
11
Issue
11
Rights Holder(s)
SCOPUS
Bibliographic Citation
Biomedicines Vol.11 No.11 (2023)
Suggested Citation
Lohitthai S., Rungruengkitkun A., Jitprasutwit N., Kong-Ngoen T., Duangurai T., Tandhavanant S., Sukphopetch P., Chantratita N., Indrawattana N., Pumirat P. Type VI Secretion System Accessory Protein TagAB-5 Promotes Burkholderia pseudomallei Pathogenicity in Human Microglia. Biomedicines Vol.11 No.11 (2023). doi:10.3390/biomedicines11112927 Retrieved from: https://repository.li.mahidol.ac.th/handle/20.500.14594/91339
Title
Type VI Secretion System Accessory Protein TagAB-5 Promotes Burkholderia pseudomallei Pathogenicity in Human Microglia
Other Contributor(s)
Abstract
Central nervous system (CNS) melioidosis caused by Burkholderia pseudomallei is being increasingly reported. Because of the high mortality associated with CNS melioidosis, understanding the underlying mechanism of B. pseudomallei pathogenesis in the CNS needs to be intensively investigated to develop better therapeutic strategies against this deadly disease. The type VI secretion system (T6SS) is a multiprotein machine that uses a spring-like mechanism to inject effectors into target cells to benefit the infection process. In this study, the role of the T6SS accessory protein TagAB-5 in B. pseudomallei pathogenicity was examined using the human microglial cell line HCM3, a unique resident immune cell of the CNS acting as a primary mediator of inflammation. We constructed B. pseudomallei tagAB-5 mutant and complementary strains by the markerless allele replacement method. The effects of tagAB-5 deletion on the pathogenicity of B. pseudomallei were studied by bacterial infection assays of HCM3 cells. Compared with the wild type, the tagAB-5 mutant exhibited defective pathogenic abilities in intracellular replication, multinucleated giant cell formation, and induction of cell damage. Additionally, infection by the tagAB-5 mutant elicited a decreased production of interleukin 8 (IL-8) in HCM3, suggesting that efficient pathogenicity of B. pseudomallei is required for IL-8 production in microglia. However, no significant differences in virulence in the Galleria mellonella model were observed between the tagAB-5 mutant and the wild type. Taken together, this study indicated that microglia might be an important intracellular niche for B. pseudomallei, particularly in CNS infection, and TagAB-5 confers B. pseudomallei pathogenicity in these cells.