Paramyxovirus and morbillivirus infections and their relationship to neurological disease

The Potential Role of SARS-CoV-2 Infection and Vaccines in Multiple Sclerosis Onset and Reactivation: A Case Series and Literature Review

The recent SARS-CoV-2 pandemic and related vaccines have raised several issues. Among them, the potential role of the viral infection (COVID-19) or anti-SARS-CoV-2 vaccines as causal factors of dysimmune CNS disorders, as well as the safety and efficacy of vaccines in patients affected by such diseases and on immune-active treatments have been analyzed. The aim is to better understand the relationship between SARS-CoV-2 infection/vaccines with dysimmune CNS diseases by describing 12 cases of multiple sclerosis/myelitis onset or reactivation after exposure to SARS-CoV-2 infection/vaccines and reviewing all published case reports or case series in which MS onset or reactivation was temporally associated with either COVID-19 (8 case reports, 3 case series) or anti-SARS-CoV-2 vaccines (13 case reports, 6 case series). All the cases share a temporal association between viral/vaccine exposure and symptoms onset. This finding, together with direct or immune-based mechanisms described both during COVID-19 and MS, claims in favor of a role for SARS-CoV-2 infection/vaccines in unmasking dysimmune CNS disorders. The most common clinical presentations involve the optic nerve, brainstem and spinal cord. The preferential tropism of the virus together with the presence of some host-related genetic/immune factors might predispose to the involvement of specific CNS districts.

Sensitive and broadly reactive reverse transcription-PCR assays to detect novel paramyxoviruses

We have developed a set of reverse transcription-PCR assays for the detection and identification of known and novel paramyxoviruses in clinical specimens. Primers were designed from the conserved motifs of the polymerase pol gene sequences to detect members of the Paramyxovirinae or Pneumovirinae subfamily or groups of genera within the Paramyxovirinae subfamily. The consensus-degenerate hybrid oligonucleotide primer design and seminested or nested PCR assay design were used to enhance the breadth of reactivity and sensitivity of the respective assays. Using expressed RNA and 10-fold dilution series of virus-infected tissue culture isolates from different members of the family or genera, these assays were able to detect on average between 100 and 500 copies of template RNA. The assays were specific to the respective group of genera or subfamily viruses. This set of primers enhances our ability to look for novel viruses in outbreaks and diseases of unknown etiology.

Central nervous system virion detection in acute measles: histopathological, ultrastructural and pathogenetic aspects

Histopathological and ultrastructural studies of 23 patients who died with clinical diagnosis of measles were carried out. In 12 cases viral nucleocapsids were searched by electron microscopy and detected in 100% of the cases in the lungs and in 50% of the cases in the central nervous system. They were mostly intranuclear. Histopathological changes associated to neurological alterations and the detection of virion are discussed in relation to acute and delayed clinical manifestations.

A case-control epidemiological study of MS in the Paris area with particular reference to past disease history and profession

A retrospective case-control study was carried out on 230 patients with multiple sclerosis (MS) and 230 controls matched for year of birth and sex. The geographical distribution of residence of MS patients and controls was similar. Two peak ages of onset of MS were observed among woman patients (20-24, 30-34 years). There was no difference in histories of infectious diseases and autoimmune diseases between the two groups. A greater number of hairdressers was noticed among the patient group (p less than 0.05) and three patients (no control) had had professional contact with pathology specimens.

Characterization of canine distemper viruses adapted to human neural cells

The biochemical characteristics of canine distemper virus (CDV) adapted to three human neural cells (glioblastoma, oligodendroglioma, and neuroblastoma cells) were compared with those of the unadapted original virus. The specific gravity of the virions and nucleocapsids of the original and the three adapted viruses were not different. The molecular weights of genomic RNA and messenger RNAs encoding H, F, P, and NP proteins of the adapted viruses as estimated by Northern blot hybridization were similar to those of the original virus. By T1-resistant oligonucleotide analysis of the genomic RNA, the glioblastoma- and the neuroblastoma-adapted viruses gave two more spots than the original virus; the oligodendroglioma-adapted virus had a pattern identical to that of the original virus. By two-dimensional gel electrophoresis of virion proteins, we found a difference in the isoelectric point of the viral envelope proteins H and F between the original and the adapted viruses. These results suggest that viral genomic changes occurred during adaptation, resulting in the alteration of viral envelope proteins.

Light and electron microscopical studies of the immunoperoxidase staining of multiple sclerosis plaques using antisera to a feline-derived agent and to galactocerebroside

Antibodies have been raised to two agents (CCA147 and MV631) that were isolated from central nervous tissue of cats. The cells co-cultivated with these agents are characterized by the presence of cytoplasmic inclusions consisting of 16-18 nm diameter tubular elements morphologically similar to inclusions seen in a demyelinating condition in cats and to inclusions described as 'curved linear profiles' in multiple sclerosis (MS) plaques. The peroxidase-labelled antibodies to CCA147 and MV631 stain these inclusions in MS plaques as well as small virus-like particles. The antisera do not stain normal white matter either in MS or non-MS brain tissue. The staining reaction of one agent is blocked by pretreatment with antisera to the other agent and also by pretreatment with MS sera but not by normal human sera. Peroxidase-labelled antibody to galactocerebroside stains normal myelin and myelin debris within MS plaques but does not stain the 'curved linear profiles' that are stained by the labelled antibodies to the feline-derived agents. The results show that the 'curved linear profiles' described in MS plaques are not myelin degradation products, but are comparable to the nucleocapsids of morbilliviruses. In addition, the small virus-like particles are morphologically similar to morbillivirus virions. The results are discussed with particular emphasis on the features of the morbilliviruses, canine distemper and measles viruses.