• FluTrackers.com Inc. does not provide medical advice. Information on this web site is collected from various internet resources, and the FluTrackers board of directors makes no warranty to the safety, efficacy, correctness or completeness of the information posted on this site by any author or poster. The information collated here is for instructional and/or discussion purposes only and is NOT intended to diagnose or treat any disease, illness, or other medical condition. Every individual reader or poster should seek advice from their personal physician/healthcare practitioner before considering or using any interventions that are discussed on this website. By continuing to access this website you agree to consult your personal physican before using any interventions posted on this website, and you agree to hold harmless FluTrackers.com Inc., the board of directors, the members, and all authors and posters for any effects from use of any medication, supplement, vitamin or other substance, device, intervention, etc. mentioned in posts on this website, or other internet venues referenced in posts on this website.
  • We are not asking for any donations. Do not donate to any entity who says they are raising funds for us.

Sci Adv . Receptor basis of unusual tissue tropism of avian influenza H5N1 clade 2.3.4.4b virus in cattle

tetano

Editor, Senior Moderator
Sci Adv


. 2026 Jun 19;12(25):eaea2068.
doi: 10.1126/sciadv.aea2068. Epub 2026 Jun 19.
Receptor basis of unusual tissue tropism of avian influenza H5N1 clade 2.3.4.4b virus in cattle

Surabhi Srinivas[SUP] 1 [/SUP], Shubhada K Chothe[SUP] 1 2 [/SUP], Santhamani Ramasamy[SUP] 1 2 [/SUP], Sougat Misra[SUP] 1 2 [/SUP], Noel Chandan Nallipogu[SUP] 1 [/SUP], Lindsey LaBella[SUP] 1 2 [/SUP], Yin-Ting Yeh[SUP] 3 [/SUP], May Wang[SUP] 4 [/SUP], Lauren E Pepi[SUP] 4 [/SUP], Heidi L Pecoraro[SUP] 5 [/SUP], Brett T Webb[SUP] 5 [/SUP], Suresh V Kuchipudi[SUP] 1 2 6 [/SUP]


Affiliations
Abstract

The unusual tropism of H5N1 clade 2.3.4.4b for cattle mammary glands, causing necrotizing mastitis without major respiratory involvement, raises critical questions about its underlying mechanisms. We conducted glycomics and linkage-specific lectin histochemistry to characterize sialic acid (SA) receptor diversity and anatomical distribution, and virus binding assays and high-resolution electron microscopy (EM) to visualize virus-receptor interactions. Cattle mammary gland exhibited an abundance of N- and O-linked SA glycans, showing a stronger binding affinity to clade 2.3.4.4b H5 than clade 2.2 H5. In contrast, the cattle trachea contained only O-linked but not N-linked SAs and showed no detectable H5 binding, indicating limited compatible influenza A virus (IAV) receptor availability in the tracheal epithelium. EM of virus-bound tissues further validated the receptor basis of H5N1 infection in cattle. As H5N1 continues infecting unusual hosts, as evidenced by the first case in sheep, our study offers a methodological framework for assessing IAV susceptibility.


 
Back
Top