tetano
Editor, Senior Moderator
Immunity
. 2026 Jan 30:S1074-7613(25)00569-2.
doi: 10.1016/j.immuni.2025.12.013. Online ahead of print.
Pre-existing neutralizing antibodies against cattle-transmitted influenza A virus H5N1 are detectable in unexposed individuals
Katharina Daniel[SUP] 1 [/SUP], Leon Ullrich[SUP] 1 [/SUP], Denis Ruchnewitz[SUP] 2 [/SUP], Matthijs Meijers[SUP] 2 [/SUP], Nico Joel Halwe[SUP] 3 [/SUP], Ursula Wild[SUP] 4 [/SUP], Jan Eberhardt[SUP] 2 [/SUP], Jacob Schön[SUP] 3 [/SUP], Ricarda Stumpf[SUP] 1 [/SUP], Maike Schlotz[SUP] 1 [/SUP], Marie Wunsch[SUP] 5 [/SUP], Luana Girao Lessa[SUP] 1 [/SUP], Elsayed Mohammed Abdelwhab[SUP] 6 [/SUP], Maryna Kuryshko[SUP] 6 [/SUP], Christopher Dietrich[SUP] 4 [/SUP], Andreas Pinger[SUP] 4 [/SUP], Anna-Lena Schumacher[SUP] 7 [/SUP], Maximilian Germer[SUP] 7 [/SUP], Malena Rohde[SUP] 1 [/SUP], Christian Kukat[SUP] 7 [/SUP], Lutz Gieselmann[SUP] 5 [/SUP], Henning Gruell[SUP] 1 [/SUP], Donata Hoffmann[SUP] 3 [/SUP], Martin Beer[SUP] 3 [/SUP], Thomas Erren[SUP] 4 [/SUP], Michael Lässig[SUP] 2 [/SUP], Christoph Kreer[SUP] 8 [/SUP], Florian Klein[SUP] 9 [/SUP]
Affiliations
The transmission of influenza A virus H5N1 clade 2.3.4.4b from cattle to humans highlights the risk of an H5N1 pandemic. Pre-existing immunity strongly impacts the course and severity of viral infections, making detailed knowledge of antibodies against the spilled-over strain crucial. Here, we assessed humoral immunity against H5N1 A/Texas/37/2024 in H5N1-naive individuals. We performed complementary binding and neutralization assays on 66 individuals and ranked activities among a panel of 76 influenza A virus isolates. We detected low but distinct cross-neutralizing titers against A/Texas/37/2024, with a 3.9- to 15.6-fold reduction compared with selected H1N1 or H3N2 strains. By cloning and characterizing 136 memory B cell-derived monoclonal antibodies, we identified potent A/Texas/37/2024-neutralizing antibodies in five out of six individuals we investigated. These antibodies cross-neutralized H1, competed with antibodies targeting the hemagglutinin (HA) stem, and protected mice from lethal H5N1 challenge. Our findings demonstrate partial pre-existing humoral immunity to A/Texas/37/2024 in H5N1-naive individuals.
Keywords: A/Texas/37/2024; H5N1; clade 2.3.4.4b; cross-neutralizing antibodies; highly pathogenic avian influenza; humoral immunity; influenza virus; pre-existing antibodies.
. 2026 Jan 30:S1074-7613(25)00569-2.
doi: 10.1016/j.immuni.2025.12.013. Online ahead of print.
Pre-existing neutralizing antibodies against cattle-transmitted influenza A virus H5N1 are detectable in unexposed individuals
Katharina Daniel[SUP] 1 [/SUP], Leon Ullrich[SUP] 1 [/SUP], Denis Ruchnewitz[SUP] 2 [/SUP], Matthijs Meijers[SUP] 2 [/SUP], Nico Joel Halwe[SUP] 3 [/SUP], Ursula Wild[SUP] 4 [/SUP], Jan Eberhardt[SUP] 2 [/SUP], Jacob Schön[SUP] 3 [/SUP], Ricarda Stumpf[SUP] 1 [/SUP], Maike Schlotz[SUP] 1 [/SUP], Marie Wunsch[SUP] 5 [/SUP], Luana Girao Lessa[SUP] 1 [/SUP], Elsayed Mohammed Abdelwhab[SUP] 6 [/SUP], Maryna Kuryshko[SUP] 6 [/SUP], Christopher Dietrich[SUP] 4 [/SUP], Andreas Pinger[SUP] 4 [/SUP], Anna-Lena Schumacher[SUP] 7 [/SUP], Maximilian Germer[SUP] 7 [/SUP], Malena Rohde[SUP] 1 [/SUP], Christian Kukat[SUP] 7 [/SUP], Lutz Gieselmann[SUP] 5 [/SUP], Henning Gruell[SUP] 1 [/SUP], Donata Hoffmann[SUP] 3 [/SUP], Martin Beer[SUP] 3 [/SUP], Thomas Erren[SUP] 4 [/SUP], Michael Lässig[SUP] 2 [/SUP], Christoph Kreer[SUP] 8 [/SUP], Florian Klein[SUP] 9 [/SUP]
Affiliations
- PMID: 41619731
- DOI: 10.1016/j.immuni.2025.12.013
The transmission of influenza A virus H5N1 clade 2.3.4.4b from cattle to humans highlights the risk of an H5N1 pandemic. Pre-existing immunity strongly impacts the course and severity of viral infections, making detailed knowledge of antibodies against the spilled-over strain crucial. Here, we assessed humoral immunity against H5N1 A/Texas/37/2024 in H5N1-naive individuals. We performed complementary binding and neutralization assays on 66 individuals and ranked activities among a panel of 76 influenza A virus isolates. We detected low but distinct cross-neutralizing titers against A/Texas/37/2024, with a 3.9- to 15.6-fold reduction compared with selected H1N1 or H3N2 strains. By cloning and characterizing 136 memory B cell-derived monoclonal antibodies, we identified potent A/Texas/37/2024-neutralizing antibodies in five out of six individuals we investigated. These antibodies cross-neutralized H1, competed with antibodies targeting the hemagglutinin (HA) stem, and protected mice from lethal H5N1 challenge. Our findings demonstrate partial pre-existing humoral immunity to A/Texas/37/2024 in H5N1-naive individuals.
Keywords: A/Texas/37/2024; H5N1; clade 2.3.4.4b; cross-neutralizing antibodies; highly pathogenic avian influenza; humoral immunity; influenza virus; pre-existing antibodies.