Autor: |
Lakshmi Ganapathi, Simon Van Haren, David J Dowling, Ilana Bergelson, Nikunj M Shukla, Subbalakshmi S Malladi, Rajalakshmi Balakrishna, Hiromi Tanji, Umeharu Ohto, Toshiyuki Shimizu, Sunil A David, Ofer Levy |
Jazyk: |
angličtina |
Rok vydání: |
2015 |
Předmět: |
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Zdroj: |
PLoS ONE, Vol 10, Iss 8, p e0134640 (2015) |
Druh dokumentu: |
article |
ISSN: |
1932-6203 |
DOI: |
10.1371/journal.pone.0134640 |
Popis: |
Newborns and young infants are at higher risk for infections than adults, and manifest suboptimal vaccine responses, motivating a search for novel immunomodulators and/or vaccine adjuvants effective in early life. In contrast to most TLR agonists (TLRA), TLR8 agonists such as imidazoquinolines (IMQs) induce adult-level Th1-polarizing cytokine production from human neonatal cord blood monocytes and are candidate early life adjuvants. We assessed whether TLR8-activating IMQ congeners may differ in potency and efficacy in inducing neonatal cytokine production in vitro, comparing the novel TLR7/8-activating IMQ analogues Hybrid-2, Meta-amine, and Para-amine to the benchmark IMQ resiquimod (R848).TLRA-induced NF-κB activation was measured in TLR-transfected HEK cells. Cytokine production in human newborn cord and adult peripheral blood and in monocyte-derived dendritic cell cultures were measured by ELISA and multiplex assays. X-ray crystallography characterized the interaction of human TLR8 with Hybrid-2.Hybrid-2 selectively activated both TLR7 and 8 and was more potent than R848 in inducing adult-like levels of TNF-α, and IL-1β. Consistent with its relatively high in vitro activity, crystallographic studies suggest that absence in Hybrid-2 of an ether oxygen of the C2-ethoxymethyl substituent, which can engage in unfavorable electrostatic and/or dipolar interactions with the carbonyl oxygen of Gly572 in human TLR8, may confer greater efficacy and potency compared to R848.Hybrid-2 is a selective and potent TLR7/8 agonist that is a candidate adjuvant for early life immunization. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
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