Biology subjects

Kuryshko, M.

Publications and source records attributed to Kuryshko, M..

4 recordsLinked to original sources

bioRxiv2026

Development of a multi-species luciferase-based double antigen ELISA for the detection of antibodies against Influenza A virus H5 clade 2.3.4.4b

The highly pathogenic avian influenza viruses (HPAIV) of subtype H5N1 represent a major threat to animal and public health. The current panzootic with H5 clade 2.3.4.4b has caused numerous, widespread outbreaks in various domestic and wild avian species with high mortalities, massive losses and a high frequency of spillover events to unexpected novel mammalian hosts such as dairy cows. The global H5N1 situation raises serious concerns about zoonotic risks due to effective mammal-to-mammal transmission. Therefore, it is critical to increase surveillance intensity of a broadened species range, particularly at the human-animal interface. For this purpose, reliable and cost-effective serological tools that are easy to perform and suitable for high-throughput screenings are critically needed. The newly developed double antigen ELISA format employing a luminescence-based detection technology has demonstrated to comply with such prerequisites. The assay allowed the detection of H5-specific antibodies even early after infection or vaccination in a wide range of birds and mammals including humans. It further demonstrated superior analytical sensitivity and high specificity for antibodies directed against H5 hemagglutinin of clade 2.3.4.4b as no cross-reactivity with other hemagglutinin subtypes was observed. Thus, the assay represents a valuable contribution to existing serological diagnostic tests for a clade-optimized detection of influenza A virus antibodies in a broad range of species. ImportanceThe ongoing HPAIV H5N1 panzootic has caused numerous outbreaks in domestic and wild animals with frequent spillover events to unexpected host species, which underscores the importance of an intensified surveillance. However, sensitive and specific multi-species serological assays represent a major gap. For this purpose, we developed a novel double antigen ELISA which employs an innovative luminescence-based read-out strategy. The test allowed a highly sensitive and specific detection of H5-specific antibodies even early after infection or vaccination in a wide range of avian and mammalian species including humans. It therefore represents a significant contribution to improving species-independent serological diagnostic tools for the detection of influenza A virus antibodies.

microbiology↗

bioRxiv2025

Different genetic determinants for high virulence, transmission and replication of high pathogenicity H7N7 avian influenza virus in turkeys and chickens

High pathogenicity (HP) avian influenza viruses (AIV) generally evolve from low pathogenicity (LP) precursors after transmission from wild birds to chickens (Gallus gallus domesticus) and turkeys (Meleagris gallopavo), causing severe economic losses worldwide. Turkeys are more susceptible to AIV infection than chickens and are considered potential bridging hosts that facilitate the emergence of HPAIV. Beyond the polybasic cleavage site (pCS) in hemagglutinin (HA), little is known about other virulence determinants of HPAIV in these species. In 2015, HPAIV H7N7 and its LP ancestor were isolated from the same chicken farm, which differed by 16 nonsynonymous mutations across all eight gene segments, in addition to the pCS. Here we identify the genetic determinants, including the pCS, that contributed to the HPAIV H7N7 virulence, transmission, replication, and tissue distribution in chickens and turkeys. Notably, the non-structural (NS1) or matrix (M) proteins encoding segments in turkeys, or NS segment in chickens, rendered viruses as virulent and transmissible as the original HPAIV. Endotheliotropism, observed exclusively in chickens, was driven by the pCS and, to a lesser extent, the neuraminidase (NA). In vitro, the M2-V68L mutation influenced NS1 expression and virus morphology in chicken and turkey cells. Additionally, HPAIV NS1 enhanced polymerase activity and effectively suppressed interferon induction, a process further modulated by M2-V68L. These findings underscore the critical role of turkeys as a "hub" in the evolution of HPAIV from LP precursors, offering crucial insights into the genotypic and phenotypic factors that facilitate viral adaptation in different poultry species. ImportanceHigh pathogenicity avian influenza viruses (HPAIV) cause severe economic losses for the poultry industry worldwide. HPAIV generally evolve from low pathogenicity (LP) ancestors in galliform birds, with turkeys being more susceptible to severe disease and death than chickens. The mechanisms underlying HPAIV emergence in these species remain unclear. This study reveals two distinct evolutionary pathways for HPAIV. In turkeys, both the polybasic hemagglutinin cleavage site (pCS) and mutations in the NS or M segments contributed to high virulence and transmission. In chickens, only the NS segment was critical, in addition to the pCS. These segments increased virus replication in both chicken and turkey cells. However, unlike chicken cells, the M and NS segments did not play a role in blocking the innate immune response. Understanding these species-specific mechanisms highlights the role of turkeys as a bridging host and provides insights into the molecular evolution of HPAIV from LP precursors.

microbiology↗

bioRxiv2024

In turkeys, unlike chickens, the non-structural NS1 protein does not play a significant role in the replication and tissue tropism of the H7N1 avian influenza virus

The economic losses caused by high pathogenicity (HP) avian influenza viruses (AIV) in poultry industry worldwide are enormous. Although chickens and turkeys are two closely related Galliformes, turkeys are thought to be a bridging host for the adaptation of AIV from wild birds to poultry because of their high susceptibility to AIV infections. HPAIV evolve from low pathogenicity (LP) AIV after circulation in poultry through mutations in different viral proteins, including the non-structural protein (NS1), a major interferon (IFN) antagonist of AIV. At present, it is largely unknown whether the virulence determinants of HPAIV are the same in turkeys and chickens. Previously, we showed that mutations in the NS1 of HPAIV H7N1 significantly reduced viral replication in chickens in vitro and in vivo. Here, we investigated the effect of NS1 on the replication and virulence of HPAIV H7N1 in turkeys after inoculation with recombinant H7N1 carrying a naturally truncated wild-type NS1 (with 224 amino-acid "aa" in length) or an extended NS1 with 230-aa similar to the LP H7N1 ancestor. There were no significant differences in multiple-cycle viral replication or in the efficiency of NS1 to block IFN induction in cell culture. Similarly, all viruses were highly virulent in turkeys and replicated at similar levels in various organs and swabs collected from inoculated turkeys. These results suggest that NS1 does not play a role in the virulence or replication of HPAIV H7N1 in turkeys and further indicate that the genetic determinants of HPAIV differ in these two closely related galliform species.

molecular biology↗

bioRxiv2023

H7 influenza A viruses bind sialyl-LewisX, a potential intermediate receptor between species

Influenza A viruses (IAVs) can overcome species barriers by adaptation of the receptor binding site of the hemagglutinin (HA). To initiate infection, HAs bind to glycan receptors with terminal sialic acids, which are either N-acetylneuraminic acid (NeuAc) or N-glycolylneuraminic acid (NeuGc), the latter is mainly found in horses and pigs but not in birds and humans. We investigated the influence of previously identified equine NeuGc-adapting mutations (S128T, I130V, A135E, T189A, and K193R) in avian H7 IAVs in vitro and in vivo. We observed that these mutations negatively affected viral replication in chicken cells, but not in duck cells, and positively affected replication in horse cells. In vivo, the mutations reduced virus virulence and mortality in chickens. Ducks excreted high viral loads for a longer time than chickens, although they appeared clinically healthy. To elucidate why chickens and ducks were infected by these viruses despite the absence of NeuGc, we re-evaluated the receptor binding of H7 HAs using glycan microarray and flow cytometry studies. This revealed that mutated avian H7 HAs also bound to 2,3-linked NeuAc and sialyl-LewisX, which have an additional fucose moiety in their terminal epitope, explaining why infection of ducks and chickens was possible. Interestingly, the 2,3-linked NeuAc and sialyl-LewisX epitopes were only bound when presented on tri-antennary N-glycans, emphasizing the importance of investigating the fine receptor specificities of IAVs. In conclusion, the binding of NeuGc-adapted H7 IAV to sialyl-LewisX enables viral replication and shedding by chickens and ducks, potentially facilitating interspecies transmission of equine-adapted H7 IAVs. (249 words) ImportanceInfluenza A viruses cause millions of deaths and illness in birds and mammals each year. The viral surface protein hemagglutinin initiates infection by binding to host cell terminal sialic acids. Hemagglutinin adaptations affect the binding affinity to these sialic acids and therefore the potential host species targeted. While avian and human IAVs tend to bind N-acetylneuraminic acid (a form of sialic acid), equine H7 viruses prefer binding to N-glycolylneuraminic acid (NeuGc). To better understand the function of NeuGc-specific adaptations in hemagglutinin and to elucidate interspecies transmission potential NeuGc-adapted viruses, we evaluated the effects of NeuGc-specific mutations in avian H7 viruses in chickens and ducks, important economic hosts and reservoir birds, respectively. We also examined the impact on viral replication and found a binding affinity to sialyl-LewisX, another terminal epitope. These findings are important as they contribute to the understanding of the role of sialyl-LewisX in avian influenza infection. (148 words)

molecular biology↗