Differences in engulfing ability and phagolysosome formation between mononuclear-macrophages and neutrophils during Leptospira interrogans infection
10.3760/cma.j.issn.0254-5101.2019.02.004
- VernacularTitle:单核-巨噬细胞和中性粒细胞抗问号钩端螺旋体感染能力及吞噬溶酶体形成差异性研究
- Author:
Xu CHEN
1
,
2
;
Ying LIU
;
Ming WANG
;
Jie YAN
;
Shijun LI
Author Information
1. 贵阳中医学院第二附属医院中心实验室 550003
2. 贵州省疾病预防控制中心实验中心
- Keywords:
Leptospira interrogans;
Mononuclear-macrophages;
Neutrophils;
Phagolysosome
- From:
Chinese Journal of Microbiology and Immunology
2019;39(2):100-105
- CountryChina
- Language:Chinese
-
Abstract:
Objective To understand the differences in engulfing ability and phagolysosome for-mation between mononuclear-macrophages and neutrophils during Leptospira interrogans infection. Methods Human THP-1 monocytes and HL-60 cells were pretreated with PMA ( phorbol-12-myristate-13-acetate) and ATRA ( all-trans retinoic acid) to differentiate them into mononuclear-macrophages and neutrophils, respec-tively. The phagocytosis of Leptospira interrogans in THP-1-PMA mononuclear-macrophages and HL-60-AT-RA neutrophils was detected by confocal microscopy. The morphology of intracellular Leptospira was deter-mined by transmission electron microscopy. The viability of phagocytized Leptospira and the percentages of dead Leptospira were analyzed by confocal microscopy and spectrofluorimetry, respectively. Confocal micros-copy was used to measure the formation of phagolysosomes in different phagocytes. Results Both THP-1-PMA mononuclear-macrophages and HL-60-ATRA neutrophils could phagocytize Leptospira interrogans, but the phagocytic ability of the former was notably stronger than that of the latter (P<0. 05). Intracellular Lep-tospira were surrounded by phagocytic vesicles in both types of phagocytes. THP-1-PMA mononuclear-mac-rophages were better than HL-60-ATRA neutrophils in killing intracellular Leptospira (P<0. 05). More phagolysosomes were formed in THP-1-PMA mononuclear-macrophages than in HL-60-ATRA neutrophils ( P<0. 05). Conclusions Human mononuclear-macrophages but not neutrophils act as major phagocytes that play an important role in phagocytizing and killing Leptospira during infection. Less fusion of the phagosomes with lysosomes may be responsible for the lower Leptospira-killing ability of neutrophils.