title: Immunological memory after exposure to variola virus, monkeypox virus, and vaccinia virus.
abstract: We compared cellular and humoral immunity to vaccinia virus (VV) in individuals exposed to 3 different orthopoxviruses: 154 individuals previously vaccinated with VV, 7 individuals with a history of monkeypox virus infection, and 8 individuals with a history of variola virus infection. Among individuals vaccinated >20 years prior, 9 (14%) of 66 individuals demonstrated VV-specific interferon (IFN)- gamma enzyme-linked immunospot (ELISPOT) assay responses; 21 (50%) of 42 had lymphoproliferative (LP) responses, and 29 (97%) of 30 had VV-specific neutralizing antibodies. One year after monkeypox virus infection, 6 of 7 individuals had IFN- gamma ELISPOT responses, all had VV-specific LP responses, and 3 of 7 had VV-specific neutralizing antibodies. Of 8 individuals with a history of variola virus infection, 1 had a VV-specific IFN- gamma ELISPOT response, 4 had LP responses against whole VV, 7 had LP responses against heat-denatured vaccinia antigen, and 7 had VV-specific neutralizing antibodies. Survivors of variola virus infection demonstrated VV-specific CD4 memory cell responses and neutralizing antibodies >40 years after infection.
authors.affiliation: Division of Infectious Disease, Department of Medicine, New York University School of Medicine, New York, NY 10016, USA. sumathi.sivapalasingam@gmail.com
authors.forename: Sumathi
authors.initials: S
authors.lastname: Sivapalasingam
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Kennedy
authors.forename: William
authors.initials: W
authors.lastname: Borkowsky
authors.forename: Fred
authors.initials: F
authors.lastname: Valentine
authors.forename: Ming-Xia
authors.initials: MX
authors.lastname: Zhan
authors.forename: Pamela
authors.initials: P
authors.lastname: Pazoles
authors.forename: Anna
authors.initials: A
authors.lastname: Paolino
authors.forename: Francis A
authors.initials: FA
authors.lastname: Ennis
authors.forename: Neal H
authors.initials: NH
authors.lastname: Steigbigel
mesh_terms: D000328:Adult; D000368:Aged; D000914:Antibodies, Viral / Q000097:blood; D002921:Cicatrix; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007156:Immunologic Memory; D007371:Interferon-gamma / Q000096:biosynthesis; D008297:Male; D008875:Middle Aged; D018155:Orthopoxvirus / Q000276:immunology*; D011213:Poxviridae Infections / Q000276:immunology*; D013997:Time Factors; D014765:Viral Vaccines / Q000276:immunology*; D045908:Mpox, Monkeypox
chemical_list: D000914:Antibodies, Viral; D014765:Viral Vaccines; D007371:Interferon-gamma