Optimization of peptide-based ELISA for serological diagnostics: A retrospective study of human monkeypox infection

Melissa E. Dubois, Erika Hammarlund, Mark Slifka

    Research output: Contribution to journalArticle

    12 Citations (Scopus)

    Abstract

    Although smallpox has been eradicated, other diseases caused by virulent orthopoxviruses such as monkeypox virus (MPV) remain endemic in remote areas of western and central sub-Saharan Africa, and represent a potential biothreat due to international travel and/or inadvertent exposure. Unfortunately, extensive antigenic cross-reactivity among orthopoxviruses presents a challenge to serological diagnosis. We previously reported a 20mer peptide-based ELISA that identified recent MPV infection with >90% sensitivity and >90% specificity. However, the sensitivity of this approach was not determined with samples obtained at later time points after antibody titers had declined from their peak levels. To improve assay sensitivity for detecting MPV-specific antibodies at later time points, we compared diagnostic 20mer peptides to 30mer peptides. In addition, optimal 30mer peptides were tested in combination or after conjugating selected peptides to a carrier protein (bovine serum albumin) to further improve assay performance. An optimized combination of four unconjugated 30mer peptides provided 100% sensitivity for detecting MPV infection at 2-6 months post-infection, 45% sensitivity for detecting MPV infection at >2 years post-infection, and 99% specificity. However, an optimized combination of two peptide conjugates provided 100% sensitivity for detecting MPV infection at 2-6 months post-infection, 90% sensitivity for detecting MPV infection at >2 years post-infection, and 97% specificity. Peptide-based ELISA tests provide a relatively simple approach for serological detection of MPV infection. Moreover, the systematic approach used here to optimize diagnostic peptide reagents is applicable to developing improved diagnostics to a broad range of other viruses, and may be particularly useful for distinguishing between closely-related viruses within the same genus or family.

    Original languageEnglish (US)
    Pages (from-to)400-409
    Number of pages10
    JournalVector-Borne and Zoonotic Diseases
    Volume12
    Issue number5
    DOIs
    StatePublished - May 1 2012

    Fingerprint

    Monkeypox
    Monkeypox virus
    Retrospective Studies
    Enzyme-Linked Immunosorbent Assay
    Virus Diseases
    Peptides
    Infection
    Orthopoxvirus
    Viruses
    Central Africa
    Smallpox
    Antibodies
    Africa South of the Sahara
    Bovine Serum Albumin
    Carrier Proteins

    Keywords

    • Antibody
    • Diagnostics
    • ELISA
    • Monkeypox
    • Peptide

    ASJC Scopus subject areas

    • Infectious Diseases
    • Microbiology
    • Virology

    Cite this

    Optimization of peptide-based ELISA for serological diagnostics : A retrospective study of human monkeypox infection. / Dubois, Melissa E.; Hammarlund, Erika; Slifka, Mark.

    In: Vector-Borne and Zoonotic Diseases, Vol. 12, No. 5, 01.05.2012, p. 400-409.

    Research output: Contribution to journalArticle

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