Liver infiltrating mononuclear cells in children with type 1 autoimmune hepatitis.
OBJECTIVE
To investigate infiltrating cells in the liver of children with type 1 autoimmune hepatitis (AH-1).


METHODS
liver biopsies from 24 untreated AH-1 patients (14 children, 10 adults), five patients with hepatitis C virus related chronic hepatitis (HCV), and 10 control liver specimens (CL) were processed for immunohistochemical cell characterisation.


RESULTS
Two different cell distribution patterns were detected in the liver of patients with AH-1: (1) CD4(+) and CD20(+) cells were found in the central areas of the portal tracts (portal distribution); (2) CD8(+) cells were observed at the periphery of the portal space (periportal distribution). Some cell subsets, like CD56, CD57, Fas-L, and Bak, showed a non-defined distribution pattern. The presence of two well defined patterns of cell distribution was not observed in HCV and CL (CD4(+), CD20(+), and CD8(+) cells were uniformly distributed in the portal space). In AH-1 and CL, the NK markers CD56 and CD57 were found scattered throughout the liver parenchyma. However, in HCV biopsies, CD56(+) cells were also clearly increased in both the portal and the periportal areas. Biopsies of AH-1 and HCV patients showed a uniform distribution of Fas-L and Bak in the portal and periportal areas, with Bak staining also detected in the hepatic parenchyma.


CONCLUSIONS
Despite clinical and genetic differences, there was a similar distribution of liver infiltrating mononuclear cells in children and adults with AH-1. These results raise the possibility of reclassifying cryptogenic chronic hepatitis by immunohistochemical analysis of infiltrating liver cells.
División inmunogenética, Hospital de Clínicas José de San Martín, Universidad de Buenos Aires, Buenos Aires, Argentina.
M B
MB
De Biasio
N
N
Periolo
A
A
Avagnina
M T
MT
García de Dávila
M
M
Ciocca
J
J
Goñi
E
E
de Matteo
C
C
Galoppo
M C
MC
Cañero-Velasco
H
H
Fainboim
A E
AE
Muñoz
L
L
Fainboim
A C
AC
Cherñavsky
D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D019002:CD56 Antigen / Q000032:analysis; D018959:CD57 Antigens / Q000032:analysis; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D053222:Fas Ligand Protein; D005260:Female; D016174:Hepacivirus; D019698:Hepatitis C, Chronic / Q000276:immunology; D019693:Hepatitis, Autoimmune / Q000276:immunology*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D016130:Immunophenotyping / Q000379:methods; D007963:Leukocytes, Mononuclear / Q000276:immunology*; D008099:Liver / Q000276:immunology*; D008297:Male; D008562:Membrane Glycoproteins / Q000032:analysis; D048069:Tumor Necrosis Factors / Q000032:analysis; D050998:bcl-2 Homologous Antagonist-Killer Protein / Q000032:analysis
D019002:CD56 Antigen; D018959:CD57 Antigens; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D008562:Membrane Glycoproteins; D048069:Tumor Necrosis Factors; D050998:bcl-2 Homologous Antagonist-Killer Protein