High expression of eosinophil chemoattractant ecalectin/galectin-9 in drug-induced liver injury.
BACKGROUND
Ecalectin/galectin-9 (ECL/GL9) is an eosinophil chemoattractant isolated from T lymphocytes. Drug-induced liver injury (DILI), often caused by an allergic mechanism, is occasionally accompanied by eosinophilic infiltration. In this study, we intended to determine whether DILI can induce augmentation of ECL/GL9 expression. Further, we investigated whether this augmentation is associated with tissue eosinophilia.


METHODS
We examined the expression of ECL/GL9 in biopsy specimens of DILI using the immunohistochemical technique. A rabbit anti-ECL/GL9 antibody was produced by immunizing rabbits with synthetic peptide corresponding to a molecular epitope of ECL/GL9. Thereafter, immunohistochemical staining with the use of this antibody was performed on 16 DILI needle biopsy specimens, and on biopsy specimens of chronic viral hepatitis, liver cirrhosis, and normal liver tissues as controls.


RESULTS
In all cases of DILI specimens, but not in control liver specimens, a clear positive staining for ECL/GL9 was observed. Such positive staining was noted on Kupffer cells, fibroblasts, and histiocytes, but not on lymphocytes or hepatocytes. However, the intensity of immunolabeling did not correlate with the extent of eosinophile leukocyte infiltration.


CONCLUSIONS
High expression of ECL/GL9 is suggested to be a specific finding of DILI. However, tissue eosinophilia in DILI cannot be explained by the augmentation of ECL/GL9 expression.
Takahashi
Yoshihisa
Y
Department of Pathology, Teikyo University School of Medicine, Tokyo, Japan. ytakaha-tky@umin.ac.jp
Fukusato
Toshio
T
Kobayashi
Yuko
Y
Akiyama
Shuichi
S
Tamatani
Takuya
T
Shiga
Junji
J
Mori
Shigeo
S
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000032:analysis; D001707:Biopsy, Needle; D056486:Chemical and Drug Induced Liver Injury; D002630:Chemotactic Factors; D064420:Drug-Related Side Effects and Adverse Reactions; D004804:Eosinophils / Q000166:cytology; D005260:Female; D005500:Follow-Up Studies; D037161:Galectins / Q000032:analysis / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D008107:Liver Diseases / Q000453:epidemiology / Q000473:pathology*; D008111:Liver Function Tests; D008297:Male; D037241:Mannose-Binding Lectins / Q000032:analysis / Q000378:metabolism*; D008875:Middle Aged; D011379:Prognosis; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
D015415:Biomarkers; D002630:Chemotactic Factors; D037161:Galectins; D037241:Mannose-Binding Lectins