SARS-CoV-2 spike protein does not alter plasma fibrin clots
Year: 2026
Type: article
Abstract: In the article entitled "SARS-CoV-2 spike protein can bind fibrin(ogen), but does not alter plasma fibrin formation, clot structure, or lysis," 1 we reproduced the reported finding that soluble spike protein (SP) binds immobilized fibrinogen 2 and found that fibrinogen in solution binds immobilized SP.However, an important additional new result was that no binding was detected between these proteins in solution.Moreover, despite carefully replicating (and building on) the experimental conditions of Ryu et al, 2 we observed no impact of SP on fibrin clot properties using human plasma.In their letter, Pretorius and Kell 3 take issue with the overarching conclusion of our work.Although SP or SP fragments have been identified within the thrombi of infected patients, 4 a key question is whether SP alters plasma fibrin formation and breakdown.It is suggested, without evidence, that once in a plasma milieu the small amount of SP relative to fibrinogen forms a nonfunctional complex.These authors appear to fail to recognize the core tenet of their stated hypothesis.If SP associates with fibrinogen and the trace amounts of these complexes are partitioned from the bulk functional fibrinogen, they would be incapable of influencing clot dynamics.This is exactly what our data reveal using the turbidimetric assays of formation and lysis and confocal microscopy-based analyses of structure.Thus, their hypothesis, even if true, supports our conclusion that SP does not alter plasma fibrin formation, clot structure, or lysis.
Source: Blood Advances
Institution: University of North Carolina at Chapel Hill
Language: English
Subfield: Pulmonary and Respiratory Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $3,800
OpenAlex ID: W7167684659