title: PD-L1 expression induced by the 2009 pandemic influenza A(H1N1) virus impairs the human T cell response.
abstract: PD-L1 expression plays a critical role in the impairment of T cell responses during chronic infections; however, the expression of PD-L1 on T cells during acute viral infections, particularly during the pandemic influenza virus (A(H1N1)pdm09), and its effects on the T cell response have not been widely explored. We found that A(H1N1)pdm09 virus induced PD-L1 expression on human dendritic cells (DCs) and T cells, as well as PD-1 expression on T cells. PD-L1 expression impaired the T cell response against A(H1N1)pdm09 by promoting CD8⁺ T cell death and reducing cytokine production. Furthermore, we found increased PD-L1 expression on DCs and T cells from influenza-infected patients from the first and second 2009 pandemic waves in Mexico City. PD-L1 expression on CD8⁺ T cells correlated inversely with T cell proportions in patients infected with A(H1N1)pdm09. Therefore, PD-L1 expression on DCs and T cells could be associated with an impaired T cell response during acute infection with A(H1N1)pdm09 virus.
authors.affiliation: Medical Research Unit on Immunochemistry (UIMIQ), Specialties Hospital, National Medical Centre "Siglo XXI," Mexican Social Security Institute (IMSS), 06720 México, DF, Mexico ; Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, 11340 México, DF, Mexico.
authors.forename: Nuriban
authors.initials: N
authors.lastname: Valero-Pacheco
authors.forename: Lourdes
authors.initials: L
authors.lastname: Arriaga-Pizano
authors.forename: Eduardo
authors.initials: E
authors.lastname: Ferat-Osorio
authors.forename: Luz María
authors.initials: LM
authors.lastname: Mora-Velandia
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Pastelin-Palacios
authors.forename: Miguel Ángel
authors.initials: MÁ
authors.lastname: Villasís-Keever
authors.forename: Celia
authors.initials: C
authors.lastname: Alpuche-Aranda
authors.forename: Luvia Enid
authors.initials: LE
authors.lastname: Sánchez-Torres
authors.forename: Armando
authors.initials: A
authors.lastname: Isibasi
authors.forename: Laura
authors.initials: L
authors.lastname: Bonifaz
authors.forename: Constantino
authors.initials: C
authors.lastname: López-Macías
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D060890:B7-H1 Antigen / Q000235:genetics*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D016022:Case-Control Studies; D003713:Dendritic Cells / Q000276:immunology / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D007251:Influenza, Human / Q000235:genetics* / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D015398:Signal Transduction; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism*; D055815:Young Adult
chemical_list: D060890:B7-H1 Antigen; C423236:CD274 protein, human