2. Academic Validation
  3. Microglial CD2AP deficiency exerts protection in an Alzheimer's disease model of amyloidosis

Microglial CD2AP deficiency exerts protection in an Alzheimer's disease model of amyloidosis

  • Mol Neurodegener. 2024 Dec 18;19(1):95. doi: 10.1186/s13024-024-00789-7.
Lingliang Zhang # 1,  Lingling Huang # 1,  Yuhang Zhou 1,  Jian Meng 1,  Liang Zhang 1,  Yunqiang Zhou 1,  Naizhen Zheng 1,  Tiantian Guo 1,  Shanshan Zhao 1,  Zijie Wang 1,  Yuanhui Huo 1,  Yingjun Zhao 1,  Xiao-Fen Chen 1,  Honghua Zheng 1,  David M Holtzman 2,  Yun-Wu Zhang 3
Affiliations

Affiliations

  • 1 Xiamen Key Laboratory of Brain Center, The First Affiliated Hospital of Xiamen University, and Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian, 361102, China.
  • 2 Department of Neurology, Hope Center for Neurological Disorders, Knight Alzheimer's Disease Research Center, Washington University School of Medicine, St. Louis, MO, USA.
  • 3 Xiamen Key Laboratory of Brain Center, The First Affiliated Hospital of Xiamen University, and Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research, Institute of Neuroscience, School of Medicine, Xiamen University, Xiamen, Fujian, 361102, China. yunzhang@xmu.edu.cn.
  • # Contributed equally.
PMID: 39695808 DOI: 10.1186/s13024-024-00789-7
Abstract

Background: The CD2-associated protein (CD2AP) was initially identified in peripheral immune cells and regulates Cytoskeleton and protein trafficking. Single nucleotide polymorphisms (SNPs) in the CD2AP gene have been associated with Alzheimer's disease (AD). However, the functional role of CD2AP, especially its role in microglia during AD onset, remains elusive.

Methods: CD2AP protein levels in cultured primary cells and in 5xFAD mice was studied. Microglial CD2AP-deficient mice were crossed with 5xFAD mice and the offspring were subjected to neuropathological assessment, behavioral tests, electrophysiology, RNA-seq, Golgi staining, and biochemistry analysis. Primary microglia were also isolated for assessing their uptake and morphology changes.

Results: We find that CD2AP is abundantly expressed in microglia and its levels are elevated in the brain of AD patients and the 5xFAD model mice at pathological stages. We demonstrate that CD2AP haploinsufficiency in microglia significantly attenuates cognitive and synaptic deficits, weakens the response of microglia to Aβ and the formation of disease-associated microglia (DAM), and alleviates synapse loss in 5xFAD mice. We show that CD2AP-deficient microglia exhibit compromised uptake ability. In addition, we find that CD2AP expression is positively correlated with the expression of the complement C1q that is important for synapse phagocytosis and the formation of DAM in response to Aβ deposition. Moreover, we reveal that CD2AP interacts with colony stimulating factor 1 receptor (CSF1R) and regulates CSF1R cell surface levels, which may further affect C1q expression.

Conclusions: Our results demonstrate that CD2AP regulates microgliosis and identify a protective function of microglial CD2AP deficiency against Aβ deposition, suggesting the importance of detailed investigation of AD-associated genes in different brain cells for thoroughly understanding their exact contribution to AD.

Keywords

Alzheimer’s disease; C1q; CD2AP; CSF1R; Disease-associated microglia; Microglia; β-amyloid.

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