Lytic granule exocytosis at immune synapses: lessons from neuronal synapses

Hsin-Fang Chang; Claudia Schirra; Varsha Pattu; Elmar Krause; Ute Becherer

doi:10.3389/fimmu.2023.1177670

Lytic granule exocytosis at immune synapses: lessons from neuronal synapses

Front Immunol. 2023 May 18:14:1177670. doi: 10.3389/fimmu.2023.1177670. eCollection 2023.

Authors

Hsin-Fang Chang¹, Claudia Schirra¹, Varsha Pattu¹, Elmar Krause¹, Ute Becherer¹

Affiliation

¹ Department of Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), Saarland University, Homburg, Germany.

Abstract

Regulated exocytosis is a central mechanism of cellular communication. It is not only the basis for neurotransmission and hormone release, but also plays an important role in the immune system for the release of cytokines and cytotoxic molecules. In cytotoxic T lymphocytes (CTLs), the formation of the immunological synapse is required for the delivery of the cytotoxic substances such as granzymes and perforin, which are stored in lytic granules and released via exocytosis. The molecular mechanisms of their fusion with the plasma membrane are only partially understood. In this review, we discuss the molecular players involved in the regulated exocytosis of CTL, highlighting the parallels and differences to neuronal synaptic transmission. Additionally, we examine the strengths and weaknesses of both systems to study exocytosis.

Keywords: CD8+ cells; SNARE proteins; cytotoxic T lymphocytes; endocytosis; exocytosis; neuron; synapse.

Publication types

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

MeSH terms

Cell Membrane
Cytoplasmic Granules / metabolism
Exocytosis*
Synapses
T-Lymphocytes, Cytotoxic*

Grants and funding

This work was supported by grants from the Deutsche Forschungsgemeinschaft (SFB 894 to EK and UB), and the European Commission (ERC -2021-SyG_951329 to the Department of Cellular Neurophysiology, Saarland University).