Biology subjects

Thalin, C.

Publications and source records attributed to Thalin, C..

3 recordsLinked to original sources

bioRxiv2024

Neutralisation sensitivity of the SARS-CoV-2 BA.2.87.1 variant

Against the backdrop of the rapid global takeover and dominance of BA.1/BA.2 and subsequently BA.2.86 lineages, the emergence of a highly divergent SARS-CoV-2 variant warrants characterization and close monitoring. Recently, another such BA.2 descendent, designated BA.2.87.1, was detected in South Africa. Here, we show using spike-pseudotyped viruses that BA.2.87.1 is less resistant to neutralisation by prevailing antibody responses in Sweden than other currently circulating variants such as JN.1. Further we show that a monovalent XBB.1.5-adapted booster enhanced neutralising antibody titers to BA.2.87.1 by almost 4-fold. While BA.2.87.1 may not outcompete other currently-circulating lineages, the repeated emergence and transmission of highly diverged variants suggests that another large antigenic shift, similar to the replacement by Omicron, may be likely in the future.

immunology↗

bioRxiv2023

Humoral immune responses to the monovalent XBB.1.5-adapted BNT162b2 mRNA booster

Continued SARS-CoV-2 evolution and immune escape necessitated the development of updated vaccines, and a monovalent vaccine incorporating the XBB.1.5 variant spike protein is currently being rolled out. Amidst the emergence of the highly mutated BA.2.86 lineage and against the backdrop of pronounced immune imprinting, it is important to characterize the antibody responses following vaccination, particularly in the elderly. Here, we show that the monovalent XBB.1.5-adapted booster vaccination substantially enhanced both binding and neutralising antibody responses against a panel of variants, including BA.2.86, in an older population with four or more previous vaccine doses. Furthermore, neutralizing antibody titers to XBB.1.5 and BA.2.86 were boosted more strongly than titers to historical variants were. Our findings thereby suggest increased vaccine induced protection against both antigenically matched variants, as well as the more distant BA.2.86 variant, and support current vaccine policies recommending a monovalent XBB.1.5 booster dose to older individuals.

immunology↗

bioRxiv2021

Clinical grade ACE2 effectively inhibits SARS-CoV-2 Omicron infections

The recent emergence of the SARS-CoV-2 variant Omicron has caused considerable concern due to reduced vaccine efficacy and escape from neutralizing antibody therapeutics. Omicron is spreading rapidly around the globe and is suspected to account for most new COVID-19 cases in several countries, though the severity of Omicron-mediated disease is still under debate. It is therefore paramount to identify therapeutic strategies that inhibit the Omicron SARS-CoV-2 variant. Here we report using 3D structural modelling that Spike of Omicron can still associate with human ACE2. Sera collected after the second mRNA-vaccination did not exhibit a protective effect against Omicron while strongly neutralizing infection of VeroE6 cells with the reference Wuhan strain, confirming recent data by other groups on limited vaccine and convalescent sera neutralization efficacy against Omicron. Importantly, clinical grade recombinant human soluble ACE2, a drug candidate currently in clinical development, potently neutralized Omicron infection of VeroE6 cells with markedly enhanced potency when compared to reference SARS-CoV-2 isolates. These data show that SARS-CoV-2 variant Omicron can be readily inhibited by soluble ACE2, providing proof of principle of a viable and effective therapeutic approach against Omicron infections.

molecular biology↗