Main Components of Fish Immunity - 4.5. - 4.9. Cellular Immune Components

4.5. Dendritic Cells (DCs)

The DCs are among the antigen presenting cells found within several tissues and can initiate both innate and acquired immune responses [91]. DCs are characterized by their small cell bodies with many cytoplasmic processes (dendrites) [92] and have been found in gills, gut, skin, and ovaries.

 

initiate 게시되게 하다

cytoplasmic 세포질의

gut 소화관

ovaries 난소

 

Cell populations with DC-like functions and morphology have been demonstrated in many fish species [93]. With the assistance of MHC class 2 receptors, these cells deliver the processed antigens to T lymphocytes, triggering the cell-mediated acquired response.

morphology 형태학

demonstrate 보여주다

 

cell-mediated 세포 매개

Cell-Mediated Immunity
항체 생산에 의존하지 않는 면역반응 

https://bio.libretexts.org/Bookshelves/Microbiology/Microbiology_(Kaiser)/Unit_6%3A_Adaptive_Immunity/14%3A_Cell-Mediated_Immunity/14.1%3A_Cell-Mediated_Immunity_-_An_Overview

 

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These cells appear to activate T cells in an antigen-dependent manner in zebrafish by expressing genes associated with antigen presentation, such as MHC class II invariant chain iclp1, csf1r, and il12 [94].

 

antigen-dependent manner 항원의존방식

gene 유전자

 invariant 변함없는

 

The trout gut has been shown to include putative CD8 + DC-like cells that appear to have phagocytic activity and the capacity to excite naive T cells [95].

 

gut 소화관

putative 추정되는

capacity 수용력

excite 흥분시키다

 

Recently, Alesci, et al. [96] identified the intestinal DCs in several fish species including Scyliorhinus canicula (Chondrichthyes), Eptatretus cirrhatus (myxines), Polypterus senegalus (Osteichthyes, Brachiopterygii), Clarias batrachus(Osteichthyes, Teleostei), and Lepisosteus oculatus (Osteichthyes, Holostei). These findings showed that intestinal DCs and DC-like cells were positive to TLR-2, Langerin/CD207, and MHC II.

 

4.6. Lymphocytes

B lymphocytes, which are professional antigen-presenting cells (APCs) produce antibodies against antigens and mediate humoral immunity. They also develop immunological memory by differentiating into memory B cells [27].

 

mediate 중재하다

humoral immunity 체액성 면역

immunological 면역의

differentiate 구별하다

항체에 의존하지 않는 세포 매개 면역반응과 신체에서 이물질(항원)이 감지될 때 발생하는 항체 매개 반응인 체액 면역 반응

체액 면역과 세포 매개 면역은 인체가 박테리아, 바이러스, 독소와 같은 유해한 요인에 대해 표적 방식으로 스스로를 방어할 수 있도록 하는 두 가지 유형의 적응 면역 반응

항원과 항체

 

A key location for B cell production and development into mature naive B cells is the fish head kidney. Immunoglobulins are secreted into the plasma by B cells to form an antigen-binding complex [96].

 

production 생산

development 발달

secrete 분비하다

plasma 혈장

complex 덩어리

 

These secretory cells, also known as antibody secreting cells (ASCs) or plasmablasts, resemble mammalian plasma cells [97]. When B cells come into contact with antigens, activation occurs, which can be either T cell-independent (for polysaccharides- and unmethylated CpG DNA-derived antigens) or T cell-dependent (for protein-derived antigens) [98].

 

secretory 분비기관

 antibody secreting cells 항체분비세포

plasmablast 형질모세포

 mammalian 포유류

plasma 혈장

independent 독립된

polysaccharides 다당류

 unmethylated 메틸화되지 않은

derived 파생된

 

Once an antigen is bound by the BCR on an antigen-presenting B cell, the antigen is processed and delivered to T helper cells by MHC class II on the surface of B cells. T helper cells are then activated and differentiated as a result, and they subsequently express the surface protein cluster of differentiation 40 ligand (CD40L).

 

is bound 구속되다

differentiated cell 분화 세포

subsequently 그 뒤에

cluster 무리

differentiation 차별화

T 세포의 종류, 활성화, polarization(분극화) 및 기능
https://www.assaygenie.kr/blog/t-polarization-kr

 

When CD40L interacts with the B cell surface protein CD40, it causes naive B cells to activate and differentiate [99,100]. Furthermore, T cell activation is not necessary for T cell-independent B cell activation, which is triggered by the direct binding of an antigen to the BCR [99].

 

interact 상호작용하다

independent 비의존성

 

Activated B cells can either differentiate into memory B cells, which circulate throughout the body and are in charge of secondary antibody response, or into plasmablasts, which are proliferating, short-lived, and low affinity antibody-producing cells that later differentiate into plasma cells, which are not-proliferating, long-lived, or high-affinity antibody-producing cells [98].

 

 circulate 순환하다

plasmablast 형질모세포

proliferate 급증하다

affinity 친화도

 

The generation of antibody-secreting plasma cells

nutt2015.pdf

0.47MB

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When memory B cells come into contact with the same antigen, which activates their parent B cells since these two share the same surface BCR, a secondary response is generated [100].

 

activate 작동시키다

 

In the cell-mediated adaptive immune system, T cells play an inherent role in directing immune activity after the early non-specific defenses and offer an immunological response after antigen identification by APCs.

 

inherent 내재하는

 

The T cell may then direct the clearance of the foreign material by phagocytosis or cytokine stimulation after pattern recognition through the TCR. As a result, specific antigen–receptor interactions and the MHC pairing stimulate the cellular responses of the two main groups of T cells, T helper cells and cytotoxic T cells [101].

 

stimulation 자극

 interaction 상호작용

 

T cell differentiation and control are influenced in distinct ways by surrounding immunological molecules. While cytotoxic T cells are controlled by cytokine concentrations and surrounding helper T cells. T helper cells are affected by antigen binding affinity, antigen concentrations, and signaling from APCs [102].

 

differentiation 분화, 파생

 influence 영향을 주다

 distinct 분명한

concentration 농도

affinity 친화도

 

Moreover, the release of IL-2 acts as a growth promoter for the overall development of T cells [103]. After differentiation, helper T cells produce lymphotoxin (LT) to interact with intracellular pathogens and release IFN-γ to help in resisting viral infections [103].

 

lymphotoxin 림프독소

intracellular 세포내의

resist 저항하다

림프독소는 Th1 타입의 T 세포에 의해 생성되는 단백질로, 혈관의 내피세포가 대식세포들이 달라붙을 수 있도록 표면 부착 분자를 바꾸게 유도한다.

 

The helper T cells can be further classified into Th1 and Th2 according to their functions and target pathogens. The Th1 subset offers cell-mediated removal of microbes. On the other hand, the Th2 cell tends to target particular pathogens, such as parasites [104].

 

further 발전시키다

subset 부분집합

microbes 미생물

 

In teleosts, T cells are correlated to the mammalian subset and possess complementarity determining region 3 (CD3) binding domains within the TCR [105]. The head kidney and thymus nurse the developing T cells and act as a base for plasma circulating T cells. 

correlate 연관성이 있다

mammalian 포유류의

 complementarity 상보성

 

Salmonid CD3 was proven by Koppang et al.to be an effective T cell marker to assess the anatomical distributions of T cells and expression regions [105].

 

 assess 평가하다

anatomical 해부상의

distributions 분배

koppang2010.pdf

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Numerous T cells have been reported to populate the thymus before migrating to the kidney and spleen after development [101]. The antigen presentation of both MHC class I and II has demonstrated the directional activation of a T cell response, in addition to T cell characterization. MHC class I interacts with CD8 + cytotoxic T cells, whereas MHC class II helps with complex formation in T helper cells [101].

 

 directional 방향의

 

4.7. Mast Cells

In most teleost species, mast cells are a constituent of innate immunity and are located near the blood vessels in the ovaries, skin, intestine, and gills [106].

 

mast cells 비만세포

constituent 구성성분, 주민

ovaries 난소

 

The mast cell granules express S100 protein, desmin, and CD117. Moreover, their granules are stained positively with bromophenol blue and Safranin O. Using electron microscopy, these cells are characterized by the presence of numerous cytoplasmic electron-dense granules [86].

 

granule 과립

 

Several stress conditions, such as exposure to herbicide and heavy metals, chronic inflammation, and parasitic infections, cause an increased number of mast cells in the organs and tissues of teleosts [107].

 

exposure 노출

herbicide 제초제

 

Teleost fish have also demonstrated mast cell degranulation, cytokine release, and the ensuing inflammatory response after bacterial infection [108]. Piscidins, host-defense peptides, were initially discovered in hybrid striped bass. It is interesting to note that piscidins are found in mast cells, highly prevalent granulocytes that are present in all vertebrate classes [109,110].

 

degranulation 탈과립

ensue (어떤 일·결과가) 뒤따르다

initially 처음에

hybrid striped bass 화이트록 농어

prevalent 일반적인

 granulocytes 과립구

 

The recent localization of ACh in mast cells and the pavement cells, as well as the interaction of the mast cells with eosinophils and the innervation of the latter by nicotinic acetylcholine receptor (nAChR) alpha 2 subunits, were correlated with the modulation of the immune function in fish gill [111]. Both muscarinic and nicotinic cholinergic receptors have been identified on mast cells [112].

 

modulation 조절

eosinophils 산호성 백혈구

innervation 신경분포

 

4.8. Eosinophilic Granule Cells (EGCs)

Salmonids and cyprinids are among many species that frequently possess EGCs. EGCs are typically present in the skin’s epidermis, gills, connective tissue surrounding the spinal cord, and intestinal mucosa [113]. In the connective tissue stroma surrounding the bile duct, EGCs can also be identified [114].

 

spinal cord 척수

intestinal mucosa 장점막

 stroma 기질

 bile duct 담관

 

reite2006.pdf

1.11MB

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They have spherical granules in their cytoplasm that are brightly stained red by hematoxylin and eosin (HE) because they contain basic proteins. Additionally, their granules are stained deep magenta with PAS and alcian blue, due to their content of neutral and sulfated glycosaminoglycans. They exhibit a positive reaction to bromophenol blue, which shows that they contain protein, and they show a metachromatic affinity to toluidine blue. 

 

spherical 구체의

 granules 과립제

cytoplasm 세포질

 

Many functions are reported for these cells, including the release of oxygen radicals and toxic proteins onto the surface of multicellular parasites in inflammatory areas. Additionally, acute tissue damage results in EGC degranulation and release of inflammatory mediators, but chronically inflamed tissues frequently exhibit an increase in the number of these cells [115].

 

 multicellular 다세포의

 degranulation 탈괴립

mediator 중재인

chronically inflamed 만성염증

 

4.9. Rodlet Cells

Fish only have rodlet cells, which are distinguished by their thicker capsule-like cell borders and rodlet cytoplasmic inclusions [116]. The rodlet cells of the grass carp head kidney expresses α- SMA [117].

 

 

 

Rodlet cells possess an actin cytoskeleton, which may contribute to the contraction that ejects their contents. During the expulsion phase, they go through a one-way contraction that eventually destroys the cell; the rodlets and all the contents of the cell are evacuated [118].

 

contraction 수축

 eject 튀어나오게 하다

expulsion 배출, 방출

eventually 결국

 evacuate 대피시키다

 

The rodlet cells are frequently distributed in the heart, thymus, kidney, spleen, gills, skin, gall bladder, liver, blood vessel endothelium, and pancreas [106]. Several functions have been reported for these cells, including a secretory function [119], which is a defensive role, especially against parasitic helminths [79].

 

distributed 분포된

pancreas 췌장

defensive 방어의

helminths 연충류

 

They may play a role in water or electrolyte transport or lubrication, pH control, and antibiotic reactions. They may be modified goblet cells or may play a regulatory role in osmoregulation and transportation of ions. They can also be viewed as non-specific immune cells that are implicated in immunity, as they frequently occur in parasitic infestation. Rodlet cells, on the other hand, may be triggered because of tissue damage, simulating leukocyte reactions to various chemotactic stimuli [120].

 

electrolyte 전해액

화학적으로 물 또는 극성용매 속에서, 양이온과 음이온으로 전리하여, 그 용액이 전도성을 나타내는 물질

lubrication 윤활

modify 수정하다

regulatory 규제력을 지닌

osmoregulation 삼투압조졸

implicate in ~에 연루시키다

infestation (기생충) 감염

 

Moreover, rodlet cells can be regarded as a type of eosinophilic granule cell or mast cell. The nature of their contents must be determined to throw additional light on the functions of RCs. The molecular structure of RCs has been investigated using lectin histochemistry and immunohistochemistry to clearly distinguish rodlet cells from mucous cells, macrophages, and granulocytes [121].

 

be regarded as~로 여겨지다

eosinophilic 호산성의

histochemistry 조직화학

 immunohistochemistry 면역조직화학

mucous cells 점액세포

granulocytes 과립구

 

Complex carbohydrates were detected in the RCs of fish, primarily glucosidic residues of N-acetyl-galactosamine and, less commonly, N-acetyl-glucosamine and sialic acid. Sialic acid residues in the carbohydrate backbone help the mucosae to defend themselves against infections [122].

 

carbohydrates 당질

primarily 주로