Role of NLRP3 Inflammasome in Influenza A Virus H1N1 Attenuates Immunity Against Secondary MRSA Infection in Vitro
- VernacularTitle:NLRP3 炎症小体在甲型流感病毒H1N1 预感染降低小鼠巨噬细胞抗MRSA 免疫中的作用
- Author:
Xiao-han SHI
1
;
Yun-feng SHI
1
;
Jun-hui BA
1
;
Jin-mei LUO
1
;
Jia-jia HU
1
;
Ben-quan WU
1
Author Information
1. Department of MICU, Department of Pulmonary and Critical Care Medicine, the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China
- Publication Type:Journal Article
- Keywords:
NLRP3 Inflammasome;
influenza A virus H1N1;
methicillin-resistant staphylococcus aureus(MRSA);
secondary infection
- From:
Journal of Sun Yat-sen University(Medical Sciences)
2020;41(4):542-548
- CountryChina
- Language:Chinese
-
Abstract:
【Objective】 To explore the role of NLRP3 inflammasome in methicillin-resistant staphylococcus aureus(MRSA) infection secondary to influenza A virus H1N1(IAV H1N1) in vitro. 【Methods】 Macrophages RAW264.7 were cultured and then infected with only MRSA for 24 h(MRSA group) and with MRSA for 24 h secondary to H1N1 infection for 1 week in advance(MRSA+ H1N1 group), respectively. Fluorescence quantitative PCR was applied to detect the transcription of NLRP3, Caspase-1 and IL-1β, immunofluorescence and western blot were used to detect NLRP3 protein in cells, and the concentration of IL-1β in supernatant was measured by enzyme linked immunosorbent assay(ELISA) . 【Results】 In MRSA group, the transcriptions of NLRP3 and Caspase-1 mRNA, as well as translation of NLRP3, showed no difference compared with control group, while the expression of IL-1β mRNA and the concentration of IL-1β in supernatant were significantly higher than those in control group(both P<0.01). In H1N1+MRSA group, the transcription of NLRP3 and Caspase-1 were significantly higher than those in control group(both P<0.01), the translation of NLRP3 was significantly higher than that in control group(P<0.01), the concentration of IL-1β was significantly higher than that in control group(P<0.01). In H1N1+MRSA group, the transcription and translation of NLRP3 were significantly higher than those in MRSA group(both P<0.01), while the transcription of IL-1β was lower than that in MRSA group, and the concentration of IL-1β in supernatant was significantly lower than that in MRSA group(P<0.01) . 【Conclusions】 Our study suggests that IL-1β secretion induced by MRSA infection is in a NLRP3 inflammasome independent manner in macrophage. It also suggests that influenza A virus H1N1 infection in advance decreases the release of IL-1β induced by secondary MRSA infection ultimately, which may contribute to the mechanism of MRSA pneumonia secondary to IAV infection.
