High inflammation and mild demyelination in the peripheral nervous system induced by an intraneural injection of RR interleukin-4.
To examine the direct effects of IL-4 on peripheral nervous system (PNS) we injected recombinant rat IL-4 (rrIL-4) into the sciatic nerve of normal adult Lewis rats. Histopathological and immunohistochemical observations revealed that 1 day after injection, a large number of macrophages and MHC class II-positive cells appeared within both the perineurium and endoneurium. Only few CD4(+)and CD8(+)T cells existed in the endoneurium. From day 4 to day 7, we observed a gradual decline of inflammation, but the number of infiltrates in rrIL-4 injected nerves was significantly higher compared with sterile PBS-injected control group. On the contrary, demyelination affected significantly fewer nerve fibres in the rrIL-4-injected nerves compared with control group on day 7. Intraneural injection of rrIL-4 results in high grade inflammation and mild demyelination in the PNS.
Deretzi
G
G
Division of Geriatric Medicine, Karolinska Institute, Huddinge Hospital, Stockholm, Sweden.
Pelidou
S H
SH
Zou
L P
LP
Wei
L
L
Nennesmo
I
I
Zhu
J
J
D000818:Animals; D003711:Demyelinating Diseases / Q000139:chemically induced / Q000276:immunology / Q000473:pathology*; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D007249:Inflammation; D015847:Interleukin-4 / Q000633:toxicity*; D009412:Nerve Fibers / Q000473:pathology; D051381:Rats; D011917:Rats, Inbred Lew; D011994:Recombinant Proteins / Q000633:toxicity*; D012584:Sciatic Nerve / Q000187:drug effects / Q000276:immunology / Q000473:pathology*; D013997:Time Factors
D000949:Histocompatibility Antigens Class II; D011994:Recombinant Proteins; D015847:Interleukin-4