ABSTRACT
ABSTRACT Vaccination elicits a complex combination of immune responses. Immune memory formation is observed not only in the antibody responses of B-cells, but also in the T-cell response. Moreover, some live attenuated vaccines such as measles-containing vaccines can induces heterologous protection, likely through induction of memory characteristics in the innate immune response. Little is known about the immunological interaction that may occur when different vaccines are administered soon after one another, especially in relation to the novel COVID-19 vaccines. The aim of this study was to compare the innate and adaptive immune responses between persons randomized to receive either a MMR or a placebo (0.9% NaCl) injection prior to their SARS-CoV-2 mRNA vaccination. We compared: i) the cytokine and chemokine production (tumor necrosis factor [TNF]-, interleukin [IL]-1{beta}, IL-6, IL-10, IL-17, IL-22, interferon [IFN]- and IFN-{gamma}) after in-vitro stimulation of peripheral blood mononuclear cells (PBMCs) with heterologous stimuli (severe acute respiratory syndrome coronavirus [SARS-CoV]-2, measles mumps and rubella [MMR] vaccine, Toll-like receptor [TLR]-3 ligand, TLR-7/8 ligand, or TLR-4 ligand), and ii) the SARS-CoV-2 neutralizing antibody responses. Ninety-five participants in the CROWN CORONATION trial (NCT04333732; a randomized control trial comparing MMR to placebo for prevention of COVID-19) agreed to an additional single blood sample collection for this immunological study. Samples were collected around 196 (SD 22) days after administration of MMR or placebo, and around 105 (SD 27) days after their second SARS-CoV-2 mRNA vaccine injection. Twenty-four percent of participants were older than fifty and sixty-seven percent were female. The median TNF- response to stimulation with MMR was 8315.3 pg/mL in the MMR group and 4340.5 pg/mL in the placebo group; adjusted median difference (95% CI) 3012.5 (-4734.1; -323.5); p=0.017. No other significant differences were noted in the cytokine and chemokine responses between treatment groups. The SARS-CoV-2 neutralization assay geometric mean (SD) IC50 in the MMR group was 507.6 (2.6) and in the placebo group was 515.7 (2.2); ratio of geometric means (95% CI) 1.0 (0.7; 1.5). Pre-exposure to MMR vaccine was generally not associated with changes in cytokine and chemokine responses of stimulated PBMCs at 105 (27) days after SARS-CoV-2 mRNA vaccination. MMR vaccination led only to an increase of TNF- production in response to an additional ex-vivo stimulation with the MMR vaccine. The SARS-CoV-2 neutralization IC50 values did not differ between MMR and placebo groups. Further studies using a repeated measures design would be better suited to explore or rule-out any short-lived vaccine response and vaccine-vaccine immunological interaction.
Subject(s)
Necrosis , Rubella , COVID-19 , Mumps , Respiratory InsufficiencyABSTRACT
The stem-loop II motif (s2m) is an RNA element present in viruses from divergent viral families, including astroviruses and coronaviruses, but its functional significance is unknown. We created deletions or substitutions of the s2m in astrovirus VA1 (VA1), classic human astrovirus 1 (HAstV1) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). For VA1, recombinant virus could not be rescued upon partial deletion of the s2m or substitutions of G-C base pairs. Compensatory substitutions that restored the G-C base-pair enabled recovery of VA1. For HAstV1, a partial deletion of the s2m resulted in decreased viral titers compared to wild-type virus, and reduced activity in a replicon system. In contrast, deletion or mutation of the SARS-CoV-2 s2m had no effect on the ability to rescue the virus, growth in vitro, or growth in Syrian hamsters. Our study demonstrates the importance of the s2m is virus-dependent.