Interleukin 8 and CK-6 chemokines specifically attract rainbow trout (Oncorhynchus mykiss) RTS11 monocyte-macrophage cells and have variable effects on their immune functions.
In the current work, we have demonstrated that both rainbow trout (Oncorhynchus mykiss) interleukin 8 (IL-8), a CXC chemokine, and CK-6, a CC chemokine, are able of efficiently attracting RTS11, a rainbow trout established macrophage-monocyte-like cell line. Interestingly, two sub-populations of non-adherent cells are distinguishable by flow cytometry that could be identified as immature monocyte- and mature macrophage-like populations, respectively, and the two chemokines studied exert their effects on different populations. Although IL-8 specifically attracts the monocyte-like sub-population, CK-6 specifically attracts the macrophage-like cell sub-population. We have also determined the effects of both of these chemokines on RTS11 phagocytosis, respiratory burst and the expression of other immune-related genes. We found that IL-8 inhibited the phagocytosis capacity of RTS11 cells belonging to the macrophage-like profile. No effect was observed, however, on the respiratory burst, immune function that has been considerably affected throughout the establishment of the cell culture. Concerning the effect that IL-8 and CK-6 have on the expression of other immune genes, we found that IL-8 significantly induced the levels of expression of CK-6, IL-8, pro-inflammatory cytokines such as IL-1beta and tumour necrosis factor alpha (TNF-alpha) of RTS11 cells. On the other hand, CK-6 induced the levels of expression of IL-8, iNOS and the integrin CD-18, while it had very faint effect on pro-inflammatory cytokines. These results constitute one of the very few studies in which the effect of IL-8, a CXC chemokine, on monocyte-like cells is described. Moreover, it demonstrates that different monocyte-macrophage sub-populations have different reactivity to different chemokines.
Centro de Investigación en Sanidad Animal (CISA-INIA), Carretera de Algete a El Casar km. 8, 1. Valdeolmos, 28130 Madrid, Spain.
Jana
J
Montero
Julio
J
Coll
Noemí
N
Sevilla
Alberto
A
Cuesta
Niels C
NC
Bols
Carolina
C
Tafalla
D000818:Animals; D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects; D018925:Chemokines / Q000494:pharmacology*; D005434:Flow Cytometry; D005786:Gene Expression Regulation / Q000187:drug effects; D016209:Interleukin-8 / Q000494:pharmacology*; D008264:Macrophages / Q000166:cytology / Q000187:drug effects* / Q000276:immunology*; D009000:Monocytes / Q000166:cytology / Q000187:drug effects* / Q000276:immunology*; D017686:Oncorhynchus mykiss / Q000276:immunology* / Q000378:metabolism; D010586:Phagocytes / Q000187:drug effects; D016897:Respiratory Burst / Q000187:drug effects
D018925:Chemokines; D016209:Interleukin-8