Analysis of SARS-CoV-2 isolates, namely the Wuhan strain, Delta variant, and Omicron variant, identifies differential immune profiles

Abstract

There is an urgent need to better understand the impact of different severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants on immune response and disease dynamics to facilitate better intervention strategies. Here, we show that SARS-CoV-2 variants differentially affect host immune responses. The magnitude and quantity of cytokines and chemokines were comparable in those infected with the Wuhan strain and the Delta variant. However, individuals infected with the Omicron variant had significantly lower levels of these mediators. We also found an elevation of plasma galectins (Gal-3, Gal-8, and Gal-9) in infected individuals, in particular, in those with the original strain. Soluble galectins exert a proinflammatory role in COVID-19 pathogenesis. This was illustrated by their correlation with the plasma levels of sCD14, sCD163, enhanced TNF-α/IL-6 secretion, and increased SARS-CoV-2 infectivity in vitro . Moreover, we observed enhanced CD4 + and CD8 + T cell activation in Wuhan strain-infected individuals. Surprisingly, there was a more pronounced T cell activation in those infected with the Omicron in comparison to the Delta variant. In line with T cell activation status, we observed a more pronounced expansion of T cells expressing different co-inhibitory receptors in patients infected with the Wuhan strain, followed by the Omicron and Delta variants. Individuals infected with the Wuhan strain or the Omicron variant had a similar pattern of plasma soluble immune checkpoints. Our results imply that a milder innate immune response might be beneficial and protective in those infected with the Omicron variant. Our results provide a novel insight into the differential impact of SARS-CoV-2 variants on host immunity. IMPORTANCE There is a need to better understand how different SARS-CoV-2 variants influence the immune system and disease dynamics to facilitate the development of better vaccines and therapies. We compared immune responses in 140 SARS-CoV-2-infected individuals with the Wuhan strain, the Delta variant, or the Omicron variant. All these patients were admitted to the intensive care unit and were SARS-CoV-2 vaccination naïve. We found that SARS-CoV-2 variants differentially affect the host immune response. This was done by measuring soluble biomarkers in their plasma and examining different immune cells. Overall, we found that the magnitude of cytokine storm in individuals infected with the Wuhan strain or the Delta variant was greater than in those infected with the Omicron variant. In light of enhanced cytokine release syndrome in individuals infected with the Wuhan strain or the Delta variant, we believe that a milder innate immune response might be beneficial and protective in those infected with the Omicron variant.

Metabolomic and immune alterations in long COVID patients with chronic fatigue syndrome

“…Delta, Omicron, etc.) ( 80 ), further comparative studies are needed. Although sex is a crucial biological variable, the limited representation of males with LC compared to females in our cohort prevented us from observing any significant differences.…”

“…The plasma concentration of ATP was quantified using the ATPlite luminescence assay system (PerkinElmer, MA) as we have reported elsewhere ( 85 ). The plasma was subjected to ELISA kit sCD14 (R&D, 383CD-050) ( 80 ) and Anti-CaSR (EAGLE Biosciences).…”

COVID-Vaccines in Pregnancy: Maternal and Neonatal Response over the First 9 Months after Delivery

“…However, the differential immune response to SARS-CoV-2 variants in maternal immunity involves a complex interplay between antibody transfer, T-cell response, breastfeeding, and vaccination status. While maternal immunity can provide some degree of protection against SARS-CoV-2 variants, the effectiveness of this immunity may vary depending on factors such as the specific mutations present in the variants and the vaccination status of the mother [35].…”

Plasma galectin-9 relates to cognitive performance and inflammation among adolescents with vertically acquired HIV

“…Gal-9 elicits multifactorial immune responses through interactions with various cognate ligands, like Tim-3, PDI, and CD44 [ 43 – 46 ]. Gal-9 levels are perturbed in many disease conditions, including viral infections [ 47 – 49 ], which may lead to increased immune activation and exhaustion, cell death, monocyte turnover rates, perturbation of lymphocyte effector functions, and altered cytokine production [ 50 – 58 ]. Our results demonstrating Gal-9 associations with multiple soluble mediators, indicate that Gal-9 may play a central role in immune mechanisms driving HIV-associated comorbidities in adolescents.…”