The link to the 2007 article below was broken for me. I Googled and read it on NCBI.
Decades ago, vaccines developed against another coronavirus, feline infectious peritonitis virus, increased cats’ risk of developing the disease caused by the virus (T. Takano et al. J. Vet. Med. Sci. 81, 911–915; 2019). Similar phenomena have been seen in animal studies for other viruses, including the coronavirus that causes SARS (Y. W. Kam et al. Vaccine 25, 729–740; 2007).
At p 737 on the right column, the authors "could exclude this mechanism of enhancement as sera from triSpike vaccinated mice did neutralize, rather than enhance, virus infection on VeroE6 cells." So I similarly exclude ADE for this question. But in the last para. they wrote
Interestingly, we observed the enhancement phenotype only in human B cell lines but not in mouse macrophages despite the presence of FcγRII. Reasons for this are unclear, but the respective role of activating and inhibiting human FcγRII which have identical extracellular
p. 738
but heterologous intracellular domains and signaling capacities might play a role [63].