title: Validation of cytomegalovirus immune competence assays for the characterization of CD8(+) T cell responses posttransplant.
abstract: Cytomegalovirus (CMV) infection is one of the most important infectious complications of transplantation. Monitoring CMV-specific CD8 T cell immunity is useful for predicting active CMV infection and for directing targeted antiviral therapy. In this study, we examined four basic parameters for validation of CMV-specific tetramer staining and peptide stimulation assays that cover five most frequent HLA class I alleles. We also examined the potential use of CMV-specific CD8(+) T cell numbers and functional and cytolytic responses in two autologous HSCT recipients treated for multiple myeloma. The coefficient of variation (CV %) of the precision within assays was 3.1-24% for HLA-tetramer staining, 2.5-47% for IFN-γ, and 3.4-59.7% for CD107a/b production upon peptide stimulation. The precision between assays was 5-26% for tetramer staining, 4-24% for IFN-γ, and 5-48% for CD107a/b. The limit of detection was 0.1-0.23 cells/μL of blood for tetramer staining, 0-0.23 cell/μL for IFN-γ, and 0.11-0.98 cells/μL for CD107a/b. The assays were linear and specific. The reference interval with 95% confidence level was 0-18 cells/μL for tetramer staining, 0-2 cells/μL for IFN-γ, and 0-3 cells/μL for CD107a/b. Our results provide acceptable measures of test performance for CMV immune competence assays for the characterization of CD8(+) T cell responses posttransplant measured in the absolute cell count per μL of blood.
authors.affiliation: Department of Pathology, ARUP Institute for Clinical and Experimental Pathology, School of Medicine, University of Utah, 500 Chipeta Way, Salt Lake City, UT 84108, USA. eugene.v.ravkov@aruplab.com
authors.forename: Eugene V
authors.initials: EV
authors.lastname: Ravkov
authors.forename: Igor Y
authors.initials: IY
authors.lastname: Pavlov
authors.forename: Kimberly E
authors.initials: KE
authors.lastname: Hanson
authors.forename: Julio C
authors.initials: JC
authors.lastname: Delgado
mesh_terms: D000328:Adult; D000368:Aged; D000483:Alleles; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D003587:Cytomegalovirus / Q000276:immunology*; D003586:Cytomegalovirus Infections / Q000175:diagnosis / Q000209:etiology* / Q000276:immunology* / Q000821:virology; D018984:Epitopes, T-Lymphocyte / Q000235:genetics / Q000276:immunology; D005260:Female; D005805:Genes, MHC Class I / Q000276:immunology; D015234:HLA-A Antigens / Q000235:genetics / Q000276:immunology; D018380:Hematopoietic Stem Cell Transplantation / Q000009:adverse effects*; D006801:Humans; D007121:Immunocompetence; D007371:Interferon-gamma / Q000276:immunology; D052118:Lysosomal-Associated Membrane Protein 1 / Q000276:immunology; D052119:Lysosomal-Associated Membrane Protein 2 / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000276:immunology; D055815:Young Adult
chemical_list: D018984:Epitopes, T-Lymphocyte; D015234:HLA-A Antigens; D052118:Lysosomal-Associated Membrane Protein 1; D052119:Lysosomal-Associated Membrane Protein 2; D007371:Interferon-gamma