Project description:Tocilizumab, a monoclonal antibody against interleukin-6, has been used to treat cytokine release syndrome (CRS) in a subset of patients with severe COVID-19 disease. Acute ulcerative bowel disease has been only rarely documented in patients treated for rheumatological conditions. The gastrointestinal side effects seen when used in the context of COVID-19 are unknown. We present a case of COVID-19 CRS in which acute terminal ileum and perforated caecal ulceration evolved after tocilizumab exposure. We raise awareness of a possible causal relationship between even a single dose of tocilizumab and gut ulceration in patients with COVID-19. Any such drug enteropathy relationship requires watchful monitoring during upcoming trials of tocilizumab in patients with COVID-19.
Project description:Recent exposure to seasonal coronaviruses (sCoVs) may stimulate cross-reactive antibody responses against SARS-CoV-2. Previous studies have shown divergent results regarding protective or damaging immunity induced by prior exposure to sCoVs. It is still unknown whether pre-existing humoral immunity may play a role in the vaccine-induced neutralization and antibody responses. In this study, we collected 36 paired sera in healthy volunteers before and after immunization with inactivated SARS-CoV-2 vaccines, and analyzed the distribution and intensity of pre-existing antibody responses at the epitope level before vaccine immunization, as well as the relationship between pre-existing sCoVs immunity and vaccine-induced neutralization.
Project description:Recent exposure to seasonal coronaviruses (sCoVs) may stimulate cross-reactive antibody responses against SARS-CoV-2. Previous studies have shown divergent results regarding protective or damaging immunity induced by prior exposure to sCoVs. It is still unknown whether pre-existing humoral immunity may play a role in the vaccine-induced neutralization and antibody responses. In this study, we collected 36 paired sera in healthy volunteers before and after immunization with inactivated SARS-CoV-2 vaccines, and analyzed the distribution and intensity of pre-existing antibody responses at the epitope level before vaccine immunization, as well as the relationship between pre-existing sCoVs immunity and vaccine-induced neutralization.
Project description:BackgroundProcalcitonin (PCT) and C-reactive protein (CRP) were previously shown to have value for the detection of secondary infections in critically ill COVID-19 patients. However, since the introduction of immunomodulatory therapy, the value of these biomarkers is unclear. We investigated PCT and CRP kinetics in critically ill COVID-19 patients treated with dexamethasone with or without tocilizumab, and assessed the value of these biomarkers to detect secondary bacterial infections.MethodsIn this prospective study, 190 critically ill COVID-19 patients were divided into three treatment groups: no dexamethasone, no tocilizumab (D-T-), dexamethasone, no tocilizumab (D+T-), and dexamethasone and tocilizumab (D+T+). Serial data of PCT and CRP were aligned on the last day of dexamethasone treatment, and kinetics of these biomarkers were analyzed between 6 days prior to cessation of dexamethasone and 10 days afterwards. Furthermore, the D+T- and D+T+ groups were subdivided into secondary infection and no-secondary infection groups to analyze differences in PCT and CRP kinetics and calculate detection accuracy of these biomarkers for the occurrence of a secondary infection.ResultsFollowing cessation of dexamethasone, there was a rebound in PCT and CRP levels, most pronounced in the D+T- group. Upon occurrence of a secondary infection, no significant increase in PCT and CRP levels was observed in the D+T- group (p = 0.052 and p = 0.08, respectively). Although PCT levels increased significantly in patients of the D+T+ group who developed a secondary infection (p = 0.0003), this rise was only apparent from day 2 post-infection onwards. CRP levels remained suppressed in the D+T+ group. Receiver operating curve analysis of PCT and CRP levels yielded area under the curves of 0.52 and 0.55, respectively, which are both markedly lower than those found in the group of COVID-19 patients not treated with immunomodulatory drugs (0.80 and 0.76, respectively, with p values for differences between groups of 0.001 and 0.02, respectively).ConclusionsCessation of dexamethasone in critically ill COVID-19 patients results in a rebound increase in PCT and CRP levels unrelated to the occurrence of secondary bacterial infections. Furthermore, immunomodulatory treatment with dexamethasone and tocilizumab considerably reduces the value of PCT and CRP for detection of secondary infections in COVID-19 patients.
Project description:SARS-CoV-2 infection is associated with enhanced disease severity in pregnant women. Despite the potential of COVID-19 vaccines to reduce severe disease, vaccine uptake remained relatively low among pregnant women. Just as coordinated messaging from the CDC and leading obstetrics organizations began to increase vaccine confidence in this vulnerable group, the evolution of SARS-CoV-2 variants of concerns (VOC) including the Omicron VOC raised new concerns about vaccine efficacy, given their ability to escape vaccine-induced neutralizing antibodies. Early data point to a milder disease course following omicron VOC infection in vaccinated individuals. Thus, these data suggest that alternate vaccine induced immunity, beyond neutralization, may continue to attenuate omicron disease, such as antibody-Fc-mediated activity. To test whether vaccine induced antibodies raised in pregnancy continue to bind and leverage Fc-receptors against VOCs including the Omicron variant. VOC including Omicron receptor binding domain (RBD) or full Spike specific antibody isotype binding titers and FcγR binding were analyzed in pregnant women after the full dose regimen of either Pfizer/BioNTech BNT62b2 (n=10) or Moderna mRNA-1273 (n=10) vaccination using a multiplexing Luminex assay. Reduced, isotype recognition was observed to the Omicron receptor binding domain (RBD) following both vaccines, with relatively preserved, albeit reduced, recognition of Omicron full Spike by IgM and IgG antibodies. Despite the near complete loss of Fc-receptor binding to the Omicron RBD, Fc-receptor binding was more variable but largely preserved to the Omicron Spike. Reduced binding titers to the Omicron RBD aligns with observed loss of neutralizing activity. Despite the loss of neutralization, preserved, albeit reduced, Omicron Spike recognition and Fc-receptor binding potentially continues to attenuate disease severity in pregnant women.
Project description:Flow cytometry sorted B-cells reactive to ACE2 peptides isolated from peripheral blood of COVID-19 patients compared with non-reactive B-cells using pooled hashtag barcoding and 10x genomics 5'DGE kit and VDJ recombination of B-cells
Project description:BackgroundCoronavirus disease-19 (COVID-19) spans a wide spectrum of illness. Severe cases of COVID-19 can manifest inflammation in organs other than the lung, in tissues not known to support viral replication, and also in a hypercoagulable state. These observations have suggested that severe acute respiratory syndrome coronavirus 2 can provoke a hyperimmune response in some cases that could lead to secondary organ damage.MethodsWith evidence of elevated levels of interleukin-6 (IL-6) in patients with severe COVID-19, we conducted a small pilot off-label compassionate care study of the IL-6 receptor inhibitor tocilizumab in patients with severe COVID-19.ResultsA single infusion of tocilizumab in patients with severe COVID-19 manifested rapid declines in C-reactive protein and d-dimer and gradual rises in lymphocyte and platelet counts.ConclusionsThese findings suggest both pathophysiological mechanisms and clinical benefit that might be seen with IL-6 inhibition in severe COVID-19.