Involvement of Fas/Fas ligand system in the spinal cords of HTLV-I-associated myelopathy.
To investigate whether the Fas/Fas ligand (FasL) system is involved in the pathogenesis of HTLV-I associated myelopathy (HAM), expression of Fas/FasL in the spinal cord lesions of HAM patients was examined by immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR). Fas was preferentially expressed on infiltrating T cells in active-chronic lesions of HAM. FasL expression was up-regulated on various cells, mainly microglia/macrophages in active-chronic lesions. In contrast, Fas expression was markedly down-regulated in inactive-chronic lesions of HAM patients who had a long duration of illness. The expressions of Fas/FasL in inactive-chronic lesions were comparable to those of normal controls. In normal controls, vascular endothelial cells constitutively displayed both Fas and FasL immunoreactivity, while microglia expressed FasL. RT-PCR confirmed constitutive expression of both Fas mRNA and FasL mRNA in the spinal cords of HAM patients, and in controls. Our results indicate that Fas/FasL system is involved in the inflammatory process in the central nervous system of HAM patients.
Umehara
Fujio
F
The Third Department of Internal Medicine, Kagoshima University School of Medicine, Kagoshima, Japan. umehara@m2.kufm.kagoshima-u.ac.jp
Itoh
Kayoko
K
Michizono
Kumiko
K
Abe
Mayumi
M
Izumo
Shuji
S
Osame
Mitsuhiro
M
D000328:Adult; D000368:Aged; D053222:Fas Ligand Protein; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism*; D008875:Middle Aged; D009422:Nervous System Diseases / Q000378:metabolism / Q000473:pathology; D015493:Paraparesis, Tropical Spastic / Q000378:metabolism* / Q000473:pathology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013116:Spinal Cord / Q000378:metabolism*; D019014:fas Receptor / Q000378:metabolism*
C505661:FASLG protein, human; D053222:Fas Ligand Protein; D008562:Membrane Glycoproteins; D019014:fas Receptor