Lymph node angiogenesis in lymphoproliferative disorders: type II Mixed cryoglobulinemia as a model.
OBJECTIVE
Lymph node biopsies from patients with mixed cryoglobulinemia (MC) were investigated for: a) the presence of the hepatitis C virus (HCV) peptides C22 and C100; b) the degree of angiogenesis and of inflammatory infiltrate (macrophages and neutrophils); c) the distribution of laminin and type IV collagen, the main components of the subendothelial basement membrane; and d) the ultrastructural characteristics of the microvessels.


METHODS
Cryostat sections were stained by immunoperoxidase to highlight HCV peptides, endothelial cells, their basement membrane components, and inflammatory cells. Planimetric methods were applied to count the microvessels and inflammatory cells, and to evaluate the distribution pattern of the basement membrane components. Microvessels were also analysed at the ultrastructural level.


RESULTS
HCV+ lymph nodes showed higher microvessel and inflammatory cell counts than the HCV- lymph nodes. Their laminin and type IV collagen distribution and ultrastructural findings also indicated immature capillaries.


CONCLUSIONS
HCV could be introduced into the lymph nodes by infected mononuclear cells, and trigger inflammation and angiogenesis, thus contributing to the inflammatory process. Angiogenesis, in turn, could facilitate HCV dissemination and persistence in MC.
Vacca
A
A
Department of Biomedical Sciences and Human Oncology, University of Bari Medical School, Italy.
Ribatti
D
D
Fanelli
M
M
Nico
B
B
Di Reda
D
D
Minischetti
M
M
Dammacco
F
F
D001706:Biopsy; D003449:Cryoglobulinemia / Q000503:physiopathology* / Q000821:virology; D019040:E-Selectin / Q000032:analysis; D016174:Hepacivirus; D006526:Hepatitis C / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000032:analysis; D008198:Lymph Nodes / Q000098:blood supply* / Q000648:ultrastructure; D009389:Neovascularization, Pathologic; D019010:Vascular Cell Adhesion Molecule-1 / Q000032:analysis
D019040:E-Selectin; D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1