Sperm induce macrophage extracellular trap formation via phagocytosis-dependent mechanism

Chuncheng Lu; Zhao Wu; Hongbin Gao; Haiyuan Li; Renbin Deng; Ning Luo; Shipeng Fan; Xi Li; Danpeng He; Hui Zhao

doi:10.1093/biolre/ioad068

Sperm induce macrophage extracellular trap formation via phagocytosis-dependent mechanism

Biol Reprod. 2023 Sep 12;109(3):319-329. doi: 10.1093/biolre/ioad068.

Authors

Chuncheng Lu^{1

2}, Zhao Wu³, Hongbin Gao^{1

2}, Haiyuan Li^{1

2}, Renbin Deng^{1

2}, Ning Luo^{1

2}, Shipeng Fan^{1

2}, Xi Li^{1

2}, Danpeng He^{1

2}, Hui Zhao^{1

2}

Affiliations

¹ Department of Urology, The First Affiliated Hospital of Kunming Medical University, Kunming, China.
² The First Affiliated Hospital of Kunming Medical University, Yunnan Province Clinical Research Center for Chronic Kidney Disease, Kunming, China.
³ Department of Reproductive Genetics, The First Affiliated Hospital of Kunming Medical University, Kunming, China.

PMID: 37402702
DOI: 10.1093/biolre/ioad068

Abstract

Infertility is a public health concern worldwide. Asthenozoospermia is a common cause of male infertility and is characterized by decreased motility. Sperm motility ensures that sperm migrate to complete fertilization. Macrophages are an essential component of innate immunity in the female reproductive tract. Macrophage extracellular traps are induced by various microorganisms to capture and mediate the clearance of microorganisms. The relationship between sperm and macrophage extracellular traps is unclear. The human monocyte leukemia (THP-1) cells differentiated by phorbol myristate acetate (PMA) are widely used as surrogate of human macrophages. This study investigated sperm-induced macrophage extracellular trap formation and clarified some of the mechanisms affecting macrophage extracellular trap production. Sperm-induced macrophage extracellular traps were visualized and components of macrophage extracellular traps were identified by immunofluorescence analyses and scanning electron microscopy. By inhibiting macrophage extracellular trap production and macrophage phagocytosis, the relationship between macrophage phagocytosis and macrophage extracellular trap production was analyzed. Sperm could trigger PMA-differentiated THP-1 macrophages to produce extracellular traps. Sperm-triggered macrophage extracellular traps are dependent on phagocytosis and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Sperm from asthenozoospermia donors are more likely to be phagocytosed by macrophages than sperm from healthy donors, which induce more macrophage extracellular trap release. These data confirm the phenomenon and partial mechanism of sperm-induced macrophage extracellular trap formation in vitro. These may partly provide evidence to explain the mechanisms of clearing abnormally morphological or hypomotile sperm in the female reproductive tract and the rationale for the decreased probability of successful fertilization in asthenozoospermia.

Keywords: asthenozoospermia; macrophage extracellular traps (METs); phagocytosis; sperm; sperm motility.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Asthenozoospermia*
Extracellular Traps*
Female
Humans
Macrophages
Male
Phagocytosis
Semen
Sperm Motility
Spermatozoa