猪圆环病毒2型与猪细小病毒共感染对猪肺泡巨噬细胞吞噬功能及其干扰素表达水平的影响

Coinfection effects of porcine circovirus type 2 and porcine parvovirus in vivo on phagocytosis and interferon mRNA expression of porcine alveolar macrophages

摘要:

摘要：【目的】分析猪圆环病毒2型（PCV2）与猪细小病毒（PPV）共感染对猪肺泡巨噬细胞（PAM）吞噬功能及其干扰素表达水平的影响，为进一步阐明猪断奶后多系统衰减综合征的发病机制提供实验依据。【方法】将48头5周龄健康仔猪随机分为PCV2组、PPV组、PCV2/PPV组和对照组，每组12头。PCV2和PPV组经口鼻途径分别接种PCV2或PPV，PCV2/PPV组同时接种PCV2和PPV，对照组接种细胞营养液。感染后3、7、14和35 d（dpi）从每组随机选择3头剖杀，检测PAM的存活率、吞噬活性及其α1

Abstract:

Abstract: [Objective] Our study is to analyse the coinfection effects of porcine circovirus type 2 (PCV2) and porcine parvovirus (PPV) in vivo on phagocytosis and interferon mRNA expression level of porcine alveolar macrophages (PAM). [Methods] Forty-eight 5-week-old healthy piglets were divided randomly into 4 groups of 12 (PCV2, PPV, PCV2/PPV and the control groups). The piglets in PCV2 group were inoculated oronasally with 3 mL of porcine circovirus type2 (PCV2, 105.61 TCID50/0.1 mL), PPV group with 3 mL of porcine parvovirus (PPV, 106.69TCID50/0.1 mL), PCV2/PPV group with 3 mL of PCV2 and 3 mL of PPV and the control group with 3 mL of cell culture medium, respectively. Three piglets from each group were sacrificed randomly on 3, 7, 14 and 35 day post infection (dpi) and porcine alveolar macrophages (PAM) were collected to detect viability, phagocytotic capabilities and α1- and γ-interferon (IFN-α1 and IFN-γ) mRNA levels of PAM. [Results] The viabilities of PAM from PCV2 group and PCV2/PPV group became weaker than that of control group during the period of 3–14 dpi but they were similar to that of control group on 35 dpi; there was no significant difference between the viability of PCV2/PPV group and that of PCV2 group（P＞0.05）. The phagocytotic capabilities of PAM from three virus infection groups were lower than that of control group (P<0.01), among which that of PCV2/PPV group descended more drastically. IFN-α1 and IFN-γ mRNA levels in PAM from PCV2/PPV group were significantly lower than those of PCV2, PPV and control groups (P<0.01). [Conclusion] PCV2/PPV co-infection did not cause further decline of PAM viability but strongly weakened phagocytosis and constantly lowered IFN (IFN-α1 and IFN-γ) mRNA expression levels of PAM.