T-cell responses and previous exposure to hepatitis C virus in indeterminate blood donors

• Published in: The Lancet (British edition) Vol. 365; no. 9456; pp. 327 - 329
• Main Authors: Semmo, Nasser, Barnes, Eleanor, Taylor, Craig, Kurtz, John, Harcourt, Gillian, Smith, Neil, Klenerman, Paul
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 22.01.2005; Elsevier Limited
• Subjects: Adult; Aged; Antigen-Antibody Reactions; Antigens; Blood; Blood & organ donations; Blood Donors; Enzymes; Exposure; Female; Genomes; Hepacivirus - immunology; Hepacivirus - isolation & purification; Hepatitis; Hepatitis C; Hepatitis C - diagnosis; Hepatitis C - immunology; Hepatitis C Antibodies - immunology; Hepatitis C Antigens - immunology; Hepatology; Humans; Immune system; Immunoblotting; Immunoenzyme Techniques; Immunoglobulins; Infections; Laboratories; Lymphocytes T; Male; Medical screening; Middle Aged; Peptides; Proteins; Ribonucleic acid; RNA; RNA, Viral - analysis; T-Lymphocytes - immunology; Viral Core Proteins - immunology; Viral infections; Viruses; United Kingdom > UK; United States > US
• ISSN: 0140-6736; 1474-547X
• DOI: 10.1016/S0140-6736(05)17787-3

Blood donors are routinely screened for hepatitis C virus infection. Some individuals have weak or restricted virus-specific antibody responses, and are classed as indeterminate. Such donors are almost always negative for viral RNA in blood. We postulated that previous transient virus exposure might account for some of these cases. With sensitive ex-vivo analyses of T-cell responses, we identified virus-specific responses in 15 of 30 indeterminate blood donors tested, compared with none in controls (p=0·0013). Additionally, these responses were typically focused on core-derived peptides. These findings suggest previous exposure to the virus in many indeterminate blood donors.