Cutting edge: immune cells as sources and targets of the IL-10 family members?
This study investigated the expression of five novel human IL-10-related molecules and their receptors in blood mononuclear cells. IL-19 and IL-20 were found to be preferentially expressed in monocytes. IL-22 and IL-26 (AK155) expression was exclusively detected in T cells, especially upon type 1 polarization, and in NK cells. IL-24 (melanoma differentiation-associated gene 7) expression was restricted to monocytes and T cells. Detection of these molecules in lymphocytes was predominantly linked to cellular activation. Regarding T cells, IL-26 was primarily produced by memory cells, and its expression was independent on costimulation. In contrast to the high expression of receptors for IL-10 homologs in different tissues and cell lines, monocytes and NK, B, and T cells showed clear expression only of IL-10R1, IL-10R2, and IL-20R2. In these cells, IL-20R2 might be part of a still-unknown receptor complex. Therefore, immune cells may represent a major source but a minor target of the novel IL-10 family members.
Wolk
Kerstin
K
Department of Experimental Dermatology, Schering AG, and Institute of Medical Immunology, Medical School Charité, Humboldt University, Berlin, Germany.
Kunz
Stefanie
S
Asadullah
Khusru
K
Sabat
Robert
R
D016147:Genes, Tumor Suppressor; D006133:Growth Substances / Q000235:genetics*; D006801:Humans; D016753:Interleukin-10 / Q000235:genetics*; D007378:Interleukins / Q000235:genetics*; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D018123:Receptors, Interleukin / Q000235:genetics; D053701:Receptors, Interleukin-10; D000097043:Interleukin-22; D000099180:Interleukin-24
D006133:Growth Substances; D016753:Interleukin-10; D007378:Interleukins; D012333:RNA, Messenger; D018123:Receptors, Interleukin; D053701:Receptors, Interleukin-10; D000097043:Interleukin-22; D000099180:Interleukin-24; C421250:IL19 protein, human; C406767:IL26 protein, human; C422042:interleukin 20