ABSTRACT
Background: It is unknown whether individuals with neurological post-acute sequelae of COVID-19 (NeuroPASC) display altered levels of neuroimmune activity or neuronal injury. Method(s): Participants with new or worsened neurologic symptoms at least 3 months after laboratory-confirmed COVID-19 were enrolled in The COVID Mind Study at Yale. Never COVID controls (no history of COVID-19;nucleocapsid (N) antibody negative) were pre-pandemic or prospectively enrolled volunteers. CSF and plasma were assessed for neopterin and for IL-1beta, IL-1RA, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p40, IL-12p70, IL-13, MCP-1, TNFalpha by bead-based multiplex assay;and for anti-SARS-CoV-2 N antibodies by Luminex-based multiplex assay in technical replicate, normalized against bovine serum albumin conjugated beads. Plasma concentrations of D-dimer, C-reactive protein, neurofilament light chain (NFL), and glial fibrillary acid protein (GFAP) were measured using high-sensitivity immunoassays. Group comparisons used non-parametric tests. Result(s): NeuroPASC participants (n=38) were studied 329 (median) days (range 81-742) after first positive test for acute COVID-19. Cognitive impairment (84%) and fatigue (82%) were the most frequent post-COVID symptoms. NeuroPASC and controls (n=22) were median 49 vs 52 yrs old (p=0.9), 74% vs 32% female (p< 0.001), 76% vs 23% white race (p< 0.001), and 6% vs 57% smokers (p< 0.001). CSF white blood cells/mL, CSF protein, and serum:CSF albumin ratio were normal in both groups. CSF TNFalpha (0.66 vs 0.55 pg/ul) and plasma IL12p40 were higher (103.3 vs 42.7);and MCP-1 (503 vs 697 pg/ul) and IL-6 (1.32 vs 1.84 pg/ul;p < 0.05 for IL-6) were lower in NeuroPASC vs controls (p< 0.05);but none of these differences were significant after adjusting for multiple comparisons. Plasma GFAP was elevated in NeuroPASC vs controls (54.4 vs 42.3 pg/ml;adjusted p< 0.03). There were no differences in the other biomarkers tested. 10/31 and 7/31 NeuroPASC had anti-N antibodies in CSF and plasma, respectively. Conclusion(s): When comparing NeuroPASC to never COVID controls, we found no evidence of neuroinflammation (normal CSF cell count, inflammatory cytokines) or blood-brain barrier dysfunction (normal albumin ratio), and no support for ongoing neuronal damage (normal plasma NFL). Future studies should include better gender and race matched controls and should explore the significance of a persistent CNS humoral immune response to SARS-CoV-2 and elevated plasma GFAP after COVID-19. (Figure Presented).
ABSTRACT
Background: Neurocognitive symptoms are common in acute as well as convalescent (post-acute sequelae of COVID-19 [PASC]) COVID-19, but mechanisms of CNS pathogenesis are unclear. The aim of this study was to investigate cerebrospinal fluid (CSF) biomarker evidence of CNS infection, immune activation and neuronal injury in convalescent compared with acute infection. Method(s): We included 68 (35% female) patients >=18 years with CSF sampled during acute (46), 3-6 months after (22) SARS-CoV-2 infection or both (17), and 20 (70% female) healthy controls from longitudinal studies. The 22 patients sampled only at 3-6 months were recruited in a PASC protocol. CSF N-Ag was analyzed using an ultrasensitive antigen capture immunoassay platform (S-PLEX SARS-CoV-2 N Kit, Meso Scale Diagnostics, LLC. Rockville, MD). Additional analyses included CSF beta2-microglobulin (beta2M)], IFN-gamma, IL-6, TNF-alpha neurofilament light (NfL), and total and phosphorylated tau. Log-transformed CSF biomarkers were compared using ANOVA (Tukey post-hoc test). Result(s): Patients sampled during acute infection had moderate (27) or severe (19) COVID-19. In patients sampled at 3-6 months, corresponding initial severity was 10 (mild), 14 (moderate), and 15 (severe). At 3-6 months, 31/39 patients reported neurocognitive symptoms;8/17 patients also sampled during acute infection reported full recovery after 3-6 months. CSF biomarker results are shown in Figure 1. SARS-CoV-2 RNA was universally undetectable. N-Ag was detectable only during acute infection (32/35) but was undetectable in all follow up and control samples. Significantly higher CSF concentrations of beta2M (p< 0.0001), IFN-gamma (p=0.02), IL-6 (p< 0.0001) and NfL (p=0.04) were seen in acute compared to post-infection. Compared to controls, beta2M (p< .0001), IL-6 (p< 0.0001) and NfL (p=0.005) were significantly higher in acute infection. No biomarker differences were seen post-infection compared with controls. No differences were seen in CSF GFAp, t-tau or p-tau. Conclusion(s): We found no evidence of residual infection (RNA, N-Ag), inflammation (beta2M, IL-6, IFN-gamma, TNF-alpha), astrocyte activity (GFAp) or neuronal injury (NfL, tau) 3-6 months after initial COVID-19, while significantly higher concentrations of several markers were found during acute infection, suggesting that PASC may be a consequence of earlier injury rather than active CNS damage. CSF beta2M, IL-6, IFN-gamma and NfL were significantly lower after 3-6 months than during acute COVID-19 and not different from healthy controls. (Figure Presented).
ABSTRACT
Background: The underlying CNS pathogenesis in COVID-19 is not clear and viral RNA is rarely detected in cerebrospinal fluid (CSF). We measured viral antigen and biomarker profiles in CSF in relation to neurological symptoms and disease severity. Methods: We included 44 (32% female) hospitalized patients (26 moderate, 18 severe COVID-19) and 10 healthy controls (HC). 21 patients were neuroasymptomatic (NA), 23 neurosymptomatic (NS;encephalopathy=21, encephalitis=1, GBS=1). For antigen and cytokine analyses, a patient control (PC;n=41) group (COVID-negative with no sign of CNS infection in clinical CSF samples) was used. CSF nucleocapsid antigen (N-Ag) was analyzed using an ultrasensitive antigen capture immunoassay platform, S-PLEX direct detection assay, S-PLEX SARS-CoV-2 N Kit (MesoScale Diagnostics, LLC. Rockville, MD). Additional analyses included CSF neopterin, β2-microglobulin, cytokines and neurofilament light (NfL). Results: CSF N-Ag was detected in 31/35 patients (0/41 controls) while viral RNA was negative in all. CSF N-Ag was significantly correlated with CSF neopterin (r=0.38;p=0.03) and IFN-γ (r=0.42;p=0.01) adjusted for sampling day. No differences in CSF N-Ag concentrations were found between patient groups. All patient groups had markedly increased CSF neopterin, β2M, IL-6, IL-10 and TNF-α compared to controls, while IL-2, IL-1β and IFN-γ were significantly increased only in the NS group. CSF biomarkers were associated with time from symptom onset to CSF sampling. After adjusting for time of sampling, the NS group had significantly higher CSF IFN-γ (p=0.03), and showed a statistical trend towards significantly higher CSF neopterin, IL-6 and TNF-α (p=0.056-0.06) than the NA group. Additionally, age-adjusted CSF NfL was higher in the NS compared to the HC (p=0.01) group. No differences were seen in any CSF biomarkers in moderate compared to severe disease. Conclusion: Viral antigen is detectable in CSF in a majority of patients with COVID-19 despite the absence of detectable viral RNA, and is correlated to CNS immune activation markers. Patients with neurological symptoms had a more marked immune activation profile compared to NA patients, as well as signs of neuroaxonal injury compared to controls. These observations could not be attributed to a difference in COVID-19 severity. Our results highlight the importance of neurological symptoms and indicate that the CNS immune response and CNS pathogenesis can be initiated by viral components without direct viral invasion of the CNS.
ABSTRACT
Background: Both induction therapy, like oral cladribine, and B-cell depletion therapy, like rituximab, are highly effective disease modulatory treatments (DMTs) in relapsing multiple sclerosis (MS). The high economic costs of the registered DMTs may limit availability of treatment and strain health budgets worldwide. Oral cladribine is a recently approved DMT in Europe, while rituximab is used off-label, especially in Norway and Sweden. Large observational studies indicate good tolerance and treatment effects in MS and studies from other diseases indicate a good safety profile. However, to our knowledge, no phase three studies have compared rituximab with any established highly effective DMT. Formal safety data is also lacking for rituximab treatment in MS. Objectives: To perform a prospective randomized open-label blinded endpoint multicenter non-inferiority study. The primary objective is to test whether rituximab is non-inferior to oral cladribine for treatment of relapsing MS. Methods: In total 264 MS patients with relapsing MS will be recruited from 11 Norwegian centers and followed for 96 weeks. Inclusion criteria are having a relapsing MS diagnosis, age 18-65 years, at least one clinical relapse or one new T2 lesion on MRI within the last year and willingness to use contraception during the study period. Exclusion criteria are contraindications to either treatment, previous use of either or a similar treatment, or treatment with fingolimod or natalizumab (due to risk of rebound activity) within the last six months. The study participants will be treated with either cladribine or rituximab according to current guidelines. Results: The primary endpoint is difference in number of new or enlarging T2 lesions between the two groups from rebaseline at 12 weeks to the end of the study at 96 weeks. Furthermore, we will study clinical course, blood samples and MRI biomarkers to provide tools for personalized MS treatment. Finally, the health economic consequences of these treatment options will be evaluated. At the time of abstract submission, 55 patients have been included across three study sites. The Covid19 outbreak unfortunately resulted in a temporary halt in inclusion from March to May 2020, but the study has now been reopened. End of study is estimated to fall 2023. Conclusions: This study will guide clinicians and patients in future treatment choices for MS. The results will provide valuable knowledge concerning treatment strategies and can potentially have a huge impact on the costs of future MS treatments.