Evolution of Cellular Immunity Effector Cells; Perspective on Cytotoxic and Phagocytic Cellular Lineages

Abstract

The immune system has evolved to protect organisms from infections caused by bacteria, viruses, and parasitic pathogens. In addition, it provides regenerative capacities, tissue maintenance, and self/non-self recognition of foreign tissues. Phagocytosis and cytotoxicity are two prominent cellular immune activities positioned at the base of immune effector function in mammals. Although these immune mechanisms have diversified into a wide heterogeneous repertoire of effector cells, it appears that they share some common cellular and molecular features in all animals, but also some interesting convergent mechanisms. In this review, we will explore the current knowledge about the evolution of phagocytic and cytotoxic immune lineages against pathogens, in the clearance of damaged cells, for regeneration, for histocompatibility recognition, and in killing virally infected cells. To this end, we give different immune examples of multicellular organism models, ranging from the roots of bilateral organisms to chordate invertebrates, comparing to vertebrates’ lineages. In this review, we compare cellular lineage homologies at the cellular and molecular levels. We aim to highlight and discuss the diverse function plasticity within the evolved immune effector cells, and even suggest the costs and benefits that it may imply for organisms with the meaning of greater defense against pathogens but less ability to regenerate damaged tissues and organs.

Confocal Characterization of Intestinal Dendritic Cells from Myxines to Teleosts

“…Jawless vertebrates, such as myxines and lampreys, were the first to link innate responses with some adaptive elements [ 65 , 66 ]. Whereas all jawed vertebrates, from elasmobranchs to mammals, are endowed with innate and adaptive immunity [ 67 ]. In general, innate immunity is a rapid and non-specific response associated with the presence of humoral and cellular elements.…”

Self-Control of Inflammation during Tail Regeneration of Lizards

“…Accordingly, the pattern-recognition receptors (PRRs) associated with the innateimmunity are also functionally conserved and expressed in the granulocytes of diverse animals in the phylogeny [ 54 ]. PRRs recognize microbial components, known as pathogen-associated molecular patterns (PAMPs), to activate specific signaling pathways and lead to distinct anti-pathogen responses [ 55 ]. Furthermore, they can interact with the damage-associated molecular patterns (DAMPs) to initiate cellular inflammatory responses [ 56 ].…”

Morphological change and differential proteomics analysis of gill in Mytilus coruscus under starvation

“…At the same time, the results of the electron microscopy scan also provide reasonable verification of cell damage in the gill. The function of shellfish to engulf their necrotic cells and supply nutrients has been reported ( Mandujano-Tinoco et al, 2021 ). So, we speculated the intrinsic phagocytosis process under starvation as follows, the cilia cells in the gill were firstly shed and died after the starvation stimulation, and then as the blood cells flow through the gills, the granulocytes in the blood engulf these dead cells in gills and break them down into energy and nutrients to supply to other tissues.…”