pathogenesis. Clinical heterogeneity and confounding factors also impair the search for alternative mechanisms. Therefore, we studied the CSF of 13 patients with neurological symptoms during the acute phase of their hospitalization, looking for clues suggesting a specific dysimmune phenomenon.
MethodsCSF underwent conventional analysis and RT-PCR for SARS-CoV-2; a in-house HEK293 cell-based assay was also arranged to identify anti-spike antibodies. Albumin ratio, IgG index and oligoclonal bands were also assessed, along with a screening for autoimmune antibodies. First, commercial immunofluorescence and lineblot were used to detect common neuronal surface and intracellular antibodies, respectively; secondly, immunohistochemistry was performed on rat brain sections; lastly, CSF was incubated with fixed murine neuron and astrocyte cultures to confirm a potential auto-reactivity.
ResultsCSF analysis disclosed a slightly increased protein level with a non-significant cell count (0-10 cells/uL). Neither SARS-CoV-2 nor common neuronal antibodies were detectable in the CSF, but we recognized anti-spike IgGs. 69% of the samples also showed neuropil staining, some of which had a common staining pattern involving the hippocampal dentate gyrus. Rodent primary cultures confirmed the presence of autoreactive antibodies against epitopes that are expressed in cortical neurons and/or astrocytes in most samples.
ConclusionsA strong immunoreactivity against spike protein was found in the CSF of those patients, even without a significant blood brain barrier permeability. The detection of auto reactivity with two different techniques could thus represent a dysimmune response to COVID-19 infection, perhaps suggesting molecular mimicry.
Background
S100B is an established biomarker of brain development and damage. Lutein (LT) is a naturally occurring xanthophyll carotenoid mainly concentrated in the central nervous system (CNS), but its neurotrophic role is still debated. We investigated whether LT cord blood concentrations correlate with S100B in a cohort of preterm and term healthy newborns.
Methods
We conducted a prospective study on the distribution of LT and S100B in arterial cord blood of healthy preterm (n = 50) and term (n = 50) newborns.
Results
S100B and LT showed a pattern of concentration characterized by higher levels (P < 0.01, for all) at 33-36 weeks gestation (GA) followed by a progressive decrease (P < 0.01, for all) from 37 onwards with a dip at term. Both S100B and LT were gender-dependent with significantly (P < 0.01, for all) higher levels in females in preterm and term groups. S100B (R = 0.68; P < 0.001) and LT (R = 0.40; P = 0.005) correlated with GA at sampling. A positive significant correlation (R = 0.87; P < 0.001) between S100B and LT was found.
Conclusions
The present data showing a correlation between S100B and LT supports the notion of a LT trophic role in the CNS. Further investigations in high-risk infants are needed to elucidate LT involvement in the pathophysiological cascade of events leading to CNS development and damage.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.