Along the Axis between Type 1 and Type 2 Immunity; Principles Conserved in Evolution from Fish to Mammals

Biology

Takuya Yamaguchi³  Fumio Takizawa¹  Uwe Fischer³  Johannes M. Dijkstra² 

[1] Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; E-Mail:;Institute for Comprehensive Medical Science, Fujita Health University, Dengakugakubo 1-98, Toyoake, Aichi 470-1192, Japan;Laboratory of Fish Immunology, Institute of Infectology, Friedrich-Loeffler-Institut, Südufer 10, Greifswald-Insel Riems 17493, Germany; E-Mails:

关键词: immunology;    evolution;    fish;    T_H1;    T_H17;    T_reg;    T_H2;    i1-i2 axis;    cytokines;    IL-5;   

DOI  :  10.3390/biology4040814

来源: mdpi

【 摘 要 】

A phenomenon already discovered more than 25 years ago is the possibility of naïve helper T cells to polarize into T_H1 or T_H2 populations. In a simplified model, these polarizations occur at opposite ends of an “immune 1-2 axis” (i1-i2 axis) of possible conditions. Additional polarizations of helper/regulatory T cells were discovered later, such as for example T_H17 and T_reg phenotypes; although these polarizations are not selected by the axis-end conditions, they are affected by i1-i2 axis factors, and may retain more potential for change than the relatively stable T_H1 and T_H2 phenotypes. I1-i2 axis conditions are also relevant for polarizations of other types of leukocytes, such as for example macrophages. Tissue milieus with “type 1 immunity” (“i1”) are biased towards cell-mediated cytotoxicity, while the term “type 2 immunity” (“i2”) is used for a variety of conditions which have in common that they inhibit type 1 immunity. The immune milieus of some tissues, like the gills in fish and the uterus in pregnant mammals, probably are skewed towards type 2 immunity. An i2-skewed milieu is also created by many tumors, which allows them to escape eradication by type 1 immunity. In this review we compare a number of i1-i2 axis factors between fish and mammals, and conclude that several principles of the i1-i2 axis system seem to be ancient and shared between all classes of jawed vertebrates. Furthermore, the present study is the first to identify a canonical T_H2 cytokine locus in a bony fish, namely spotted gar, in the sense that it includes RAD50 and bona fide genes of both IL-4/13 and IL-3/IL-5/GM-CSF families.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.