Hepatitis C virus-specific reactivity of CD4+-lymphocytes in children born from HCV-infected women.
OBJECTIVE
T-lymphocyte reactivity against viral antigens may represent the only immunological marker of host contact with a virus. Aim of the present study was to investigate whether vertical exposure to hepatitis C virus (HCV) could activate HCV-specific T-cell responses that may represent a biomarker of previous contact with the virus, and possibly contribute to the low rate of vertical HCV transmission.


METHODS
We studied 28 children born from chronically HCV-infected mothers. HCV-specific activation and proliferation of CD4+-lymphocytes and cytokine production were evaluated in cultures of peripheral blood mononuclear cells (PBMCs) stimulated in vitro with HCV-peptides.


RESULTS
HCV-specific CD4+-cell reactivity was observed in 20 out of the 28 children (71%). The proliferation of HCV-specific CD4+-cells was more frequent and vigorous in children than in their mothers. In children, but not in the mothers, activation of CD4+-cells upon stimulation with HCV-peptides was directly correlated with proliferation. Early upon stimulation with HCV-peptides, lymphocytes from children produced lower levels of IL-10 than lymphocytes from the mothers.


CONCLUSIONS
Vertical exposure to HCV induces the development of viral-specific CD4+-cell-mediated immune responses, possibly endowed with protective function against infection, which may contribute to the low rate of vertical HCV transmission.
Della Bella
Silvia
S
Dipartimento di Scienze e Tecnologie Biomediche, Cattedra di Immunologia, Università degli Studi di Milano, Lita, via Fratelli Cervi 93, 20090 Segrate (MI), Italy.
Riva
Antonio
A
Tanzi
Elisabetta
E
Nicola
Stefania
S
Amendola
Antonella
A
Vecchi
Laura
L
Nebbia
Gabriella
G
Longhi
Renato
R
Zanetti
Alessandro R
AR
Villa
Maria L
ML
D015496:CD4-Positive T-Lymphocytes / Q000821:virology*; D002648:Child; D016207:Cytokines / Q000276:immunology; D005260:Female; D005434:Flow Cytometry; D016174:Hepacivirus / Q000276:immunology*; D018937:Hepatitis C Antibodies / Q000097:blood; D019698:Hepatitis C, Chronic / Q000276:immunology*; D006801:Humans; D008213:Lymphocyte Activation; D010446:Peptide Fragments / Q000302:isolation & purification; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000276:immunology / Q000821:virology; D014764:Viral Proteins / Q000302:isolation & purification
D016207:Cytokines; D018937:Hepatitis C Antibodies; D010446:Peptide Fragments; D014764:Viral Proteins