SARS-CoV-2 booster vaccination rescues attenuated IgG1 memory B cell response in primary antibody deficiency patients (preprint)

SARS-CoV-2 vaccines have proven effective in eliciting an immune response capable of providing protective immunity in healthy individuals. However, whether SARS-CoV-2 vaccination induces a long-lived immune response in immunocompromised individuals is poorly understood. Primary antibody deficiency (PAD) syndromes are among the most common immunodeficiency disorders in adults and are characterized by an impaired ability to mount robust antibody responses following infection or vaccination. Here, we present data from a prospective study in which we analyzed the B and T cell response in PAD patients following SARS-COV-2 vaccination. Unexpectedly, individuals with PAD syndromes mounted a SARS-CoV-2 specific B and CD4+ T cell response that was comparable in magnitude to healthy individuals. Many individuals with PAD syndromes displayed reduced IgG1+ and CD11c+ memory B cell responses following the primary vaccination series. However, the IgG1 class-switching defect was largely rescued following mRNA booster vaccination. Boosting also elicited an increase in the SARS-CoV-2-specific B and T cell response and the development of Omicron-specific memory B cells in COVID-19-naive PAD patients. Together, these data indicate that SARS-CoV-2 vaccines elicit memory B and T cells in PAD patients that may contribute to long-term protective immunity.

mRNA vaccine boosting enhances antibody responses against SARS-CoV-2 Omicron variant in patients with antibody deficiency syndromes (preprint)

Patients with primary antibody deficiency syndromes (PAD) have poor humoral immune responses requiring immunoglobulin replacement therapy. We followed PAD patients after SARS-CoV-2 vaccination by evaluating their immunoglobulin replacement products and serum for anti-spike binding, Fc{gamma}R binding, and neutralizing activities. Immunoglobulin replacement products had low anti-spike and receptor binding domain (RBD) titers and neutralizing activity. In COVID-19-naive PAD patients, anti-spike and RBD titers increased after mRNA vaccination but decreased to pre-immunization levels by 90 days. Patients vaccinated after SARS-CoV-2 infection developed higher responses comparable to healthy donors. Most vaccinated PAD patients had serum neutralizing antibody titers above an estimated correlate of protection against ancestral SARS-CoV-2 and Delta virus but not against Omicron virus, although this was improved by boosting. Thus, currently used immunoglobulin replacement products likely have limited protective activity, and immunization and boosting of PAD patients with mRNA vaccines should confer at least short-term immunity against SARS-CoV-2 variants, including Omicron.

Glucocorticoids and B Cell Depleting Agents Substantially Impair Immunogenicity of mRNA Vaccines to SARS-CoV-2 (preprint)

BackgroundIndividuals with chronic inflammatory diseases (CID) are frequently treated with immunosuppressive medications that can increase their risk of severe COVID-19. While novel mRNA-based SARS-CoV-2 vaccination platforms provide robust protection in immunocompetent individuals, the immunogenicity in CID patients on immunosuppression is not well established. Therefore, determining the effectiveness of SARS-CoV-2 vaccines in the setting of immunosuppression is essential to risk-stratify CID patients with impaired protection and provide clinical guidance regarding medication management. MethodsWe conducted a prospective assessment of mRNA-based vaccine immunogenicity in 133 adults with CIDs and 53 immunocompetent controls. Blood from participants over 18 years of age was collected before initial immunization and 1-2 weeks after the second immunization. Serum anti-SARS-CoV-2 spike (S) IgG+ binding, neutralizing antibody titers, and circulating S-specific plasmablasts were quantified to assess the magnitude and quality of the humoral response following vaccination. ResultsCompared to immunocompetent controls, a three-fold reduction in anti-S IgG titers (P=0.009) and SARS-CoV-2 neutralization (p<0.0001) were observed in CID patients. B cell depletion and glucocorticoids exerted the strongest effect with a 36- and 10-fold reduction in humoral responses, respectively (p<0.0001). Janus kinase inhibitors and antimetabolites, including methotrexate, also blunted antibody titers in multivariate regression analysis (P<0.0001, P=0.0023, respectively). Other targeted therapies, such as TNF inhibitors, IL-12/23 inhibitors, and integrin inhibitors, had only modest impacts on antibody formation and neutralization. ConclusionsCID patients treated with immunosuppressive therapies exhibit impaired SARS-CoV-2 vaccine-induced immunity, with glucocorticoids and B cell depletion therapy more severely impeding optimal responses.

Low-Cost Manually Assembled Open Source Reader for Isothermal Pathogen Detection from Saliva using RT-LAMP: SARS-CoV-2 Use Case (preprint)

Distributed 'Point-of-Care' or 'at-Home' testing is an important component for a complete suite of testing solutions. This manuscript describes the construction and operation of a platform technology designed to meet this need. The ongoing COVID-19 pandemic will be used as the proof-of-concept for the efficacy and deployment of this platform. The technology outlined consists of a one-pot, reverse-transcription loop-mediated isothermal amplification (RT-LAMP) chemistry coupled with a low-cost and user-assembled reader using saliva as input. This platform is readily adapted to a wide range of pathogens due to the genetic basis of the reaction. A complete guide to the construction of the reader as well as the production of the reaction chemistry are provided here. Additionally, analytical limit of detection data and the results from saliva testing of SARS-CoV-2, are presented. The platform technology outlined here demonstrates a rapid, distributed, molecular point-of-care solution for pathogen detection using crude sample input.

Targeted Immunosuppression Distinguishes COVID-19 from Influenza in Moderate and Severe Disease (preprint)

Coronavirus disease 2019 (COVID-19) is characterized by a high incidence of acute respiratory failure. The underlying immunopathology of that failure and how it compares to other causes of severe respiratory distress, such as influenza virus infection, are not fully understood. Here we addressed this by developing a prospective observational cohort of COVID-19 and influenza subjects with varying degrees of disease severity and assessing the quality and magnitude of their immune responses at the cellular and protein level. Additionally, we performed single-cell RNA transcriptional profiling of peripheral blood mononuclear cells from select subjects. The cohort consists of 79 COVID-19 subjects, 26 influenza subjects, and 15 control subjects, including 35 COVID-19 and 7 influenza subjects with acute respiratory failure. While COVID-19 subjects exhibited largely equivalent or greater activated lymphocyte counts compared to influenza subjects, they had fewer monocytes and lower surface HLA-class II expression on monocytes compared to influenza subjects and controls. At least two distinct immune profiles were observed by cytokine levels in severe COVID-19 patients: 3 of 71 patients were characterized by extreme inflammation, with greater than or equal to ~50% of the 35 cytokines measured greater than 2 standard deviations from the mean level of other severe patients (both influenza and COVID-19); the other immune profile, which characterized 68 of 71 subjects, had a mixed inflammatory signature, where 28 of 35 cytokines in COVID-19 patients had lower mean cytokine levels, though not all were statistically significant. Only 2 cytokines were higher in COVID-19 subjects compared to influenza subjects (IL-6 and IL-8). Influenza and COVID-19 patients could be distinguished statistically based on cytokine module expression, particularly after controlling for the significant effects of age on cytokine expression, but again with lower levels of most cytokines in COVID-19 subjects. Further, high circulating levels of IL-1RA and IL-6 were associated with increased odds of intubation in the combined influenza and COVID-19 cohort [OR = 3.93 and 4.30, respectively] as well as among only COVID-19 patients. Single cell transcriptional profiling of COVID-19 and influenza subjects with respiratory failure identified profound suppression in type I and type II interferon signaling in COVID-19 patients across multiple clusters. In contrast, COVID-19 cell clusters were enriched for alterations in metabolic, stress, and apoptotic pathways. These alterations were consistent with an increased glucocorticoid response in COVID-19 patients compared to influenza. When considered across the spectrum of innate and adaptive immune profiles, the immune pathologies underlying severe influenza and COVID-19 are substantially distinct. The majority of COVID-19 patients with acute respiratory failure do not have a cytokine storm phenotype but instead exhibit profound type I and type II IFN immunosuppression when compared to patients with acute influenza. Upregulation of a small number of inflammatory mediators, including IL-6, predicts acute respiratory failure in both COVID-19 and influenza patients.