Both Neisseria gonorrhoeae and Neisseria sicca Induce Cytokine Secretion by Infected Human Cells, but Only Neisseria gonorrhoeae Upregulates the Expression of Long Non-Coding RNAs

Abstract

Bacteria of the Neisseria genus are Gram-negative diplococci including both pathogenic and commensal species. We focused on pathogenic Neisseria gonorrhoeae and commensal Neisseria sicca. We have demonstrated that not only N. gonorrhoeae, but also N. sicca induce the secretion of pro-inflammatory cytokines IL-6, TNF-α, and chemokines CXCL8 and CCL20 by infected epithelial cells. However, N. sicca triggers a lesser effect than does N. gonorrhoeae. Furthermore, N. gonorrhoeae and N. sicca invoke distinct effects on the expression of genes (JUNB, FOSB, NFKB1, NFKBIA) encoding protein components of AP-1 and NF-κB transcription factors. We have also shown that the infection of epithelial cells by N. gonorrhoeae leads to significant overexpression of the long non-coding RNAs (lncRNAs), including MALAT1, ERICD, and RP11-510N19.5. This effect was not identified for N. sicca. In conclusion, data on the expression of lncRNAs and cytokine secretion in response to Neisseria spp. exposure indicate new directions for research on Neisseria-host interactions and can provide further insights into virulence of not only pathogenic, but also commensal Neisseria spp.