Low levels of neutralizing antibodies against XBB Omicron subvariants after BA.5 infection

Abstract

The COVID-19 response strategies in Chinese mainland were recently adjusted due to the reduced pathogenicity and enhanced infectivity of Omicron subvariants. In Chengdu, China, an infection wave was predominantly induced by the BA.5 subvariant. It is crucial to determine whether the hybrid anti-SARS-CoV-2 immunity following BA.5 infection, coupled with a variety of immune background, is sufficient to shape the immune responses against newly emerged Omicron subvariants, especially for XBB lineages. To investigate this, we collected serum and nasal swab samples from 108 participants who had been infected in this BA.5 infection wave, and evaluated the neutralization against pseudoviruses. Our results showed that convalescent sera from individuals, regardless of vaccination history, had remarkably compromised neutralization capacities against the newly emerged XBB and XBB.1.5 subvariants. Although post-vaccination with BA.5 breakthrough infection slightly elevated plasma neutralizing antibodies against a part of pseudoviruses, the neutralization activities were remarkably impaired by XBB lineages. Furthermore, we analyzed the impacts of the number of vaccinations, age, and sex on the humoral and cellular immune response after BA.5 infection. Our findings suggest that the neutralization against XBB lineages that elicited by current hybrid immunity after BA.5 infection, are remained at low levels, indicating an urgent need for the development of next-generation of COVID-19 vaccines that designed based on the XBB sub-lineages and other future variants.

Epidemiological characteristics and antibody kinetics of elderly population with booster vaccination following both Omicron BA.5 and XBB waves in China

“…Fortunately, the percentage of symptomatic infection after Omicron XBB wave was apparently decreased from 59.3% to 18.6%, indicating that the hybrid immunity may play an important role in preventing symptomatic infection 36 and the pathogenicity of Omicron XBB subvariants is not enhanced. 37 Consistent with the previous studies, 30,[38][39][40] able to provide enough protection against subsequent Omicron XBB reinfection. Importantly, our results and others both demonstrate that Omicron XBB reinfection enhances the neutralizing ability against all measured Omicron subvariants, 6,32 revealing that Omicron subvariants reinfection may alleviate WT vaccination-induced immune imprinting and generate broad neutralization responses.…”

B-cell and antibody responses to SARS-CoV-2: infection, vaccination, and hybrid immunity

“…The situation changed with the emergence of omicron variants. These strains efficiently escape from infection- and vaccination-induced immunity as well as from most monoclonal antibodies in clinical use [ 129 , 198 – 204 ]. As a result, VE against symptomatic omicron infections and hospitalization also declined after the basic immunization cycle, though the latter remained at a relatively high level [ 201 , 205 ].…”

Naked-Eye Readable Microarray for Rapid Profiling of Antibodies against Multiple SARS-CoV-2 Variants

“…1.1, and BA.4.6/BF.7 variants were found to be still relatively low in Cohort 1, suggesting that current established immunity through vaccination or large-scale infections might be mostly induced by the BA.4/BA.5 variants and might be ineffective against emerging variants of concern. The immune escape has been verified by recent studies. ,, NRM chips were able to profile clinical immune features associated with multiple SARS-CoV-2 variants, which will significantly aid in guiding future clinical prevention decision.…”

“…The immune escape has been verified by recent studies. 3,28,29 NRM chips were able to profile clinical immune features associated with multiple SARS-CoV-2 variants, which will significantly aid in guiding future clinical prevention decision.…”