Assessment of the sensitivity of anti-interferon binding and neutralizing antibody assays in patients with relapsing -remitting multiple sclerosis under interferon- beta treatment- A comparative study

Interferon beta (IFNβ) is a first line disease-modifying treatment for the management of relapsing-remitting multiple sclerosis. IFNβ preparations may elicit an immune response reflected by the development of binding- (Babs) and neutralizing- antibodies (Nabs). The detrimental effect of Nabs is depicted by attenuation of treatment effect and as a result the deterioration of clinical and radiological parameters. The incidence and titers of Nabs vary by the preparation of IFNβ used, dose, frequency and route of administration, treatment duration and type of assay being used. In this study we aimed to assess the sensitivity of the binding and the neutralizing assays in patients with relapsing-remitting multiple sclerosis under treatment with interferon-beta. The assessment of the results suggests that Western blot assay is more sensitive than ELISA for the detection of binding antibodies. The evaluation of CPE and Real-time-PCR results indicates that they possess similar sensitivity. However, CPE assay remains the gold standard method for the detection of neutralizing antibodies, based on the World Health Organization. Our results indicate that interlaboratory studies are needed for a commonly accepted assay that might reflect a reliable and cost-effective procedure for the Babs and Nabs detection in MS patients under IFNβ treatment

Stem cell factor is implicated in microenvironmental interactions and cellular dynamics of chronic lymphocytic leukemia

The inflammatory cytokine Stem Cell Factor (SCF, ligand of c-kit receptor) has been implicated as a pro-oncogenic driver and an adverse prognosticator in several human cancers. Increased SCF levels have recently been reported in a small series of patients with chronic lymphocytic leukemia (CLL), however its precise role in CLL pathophysiology remains elusive. In this study, CLL cells were found to predominantly express the membrane isoform of SCF that is known to elicit a more robust activation of the c-kit receptor. SCF was significantly overexpressed in CLL cells compared to healthy tonsillar B cells whilst it correlated with adverse-prognostic biomarkers, shorter time-to-first treatment and shorter overall survival. Activation of immune receptors and long-term cell-cell interactions with the mesenchymal stroma led to an elevation of SCF primarily in adverse-prognostic CLL cases. On the contrary, suppression of oxidative stress and the BTK inhibitor Ibrutinib negated SCF levels. Interestingly, SCF significantly correlated with mitochondrial dynamics and HIF-1α which have previously been linked with clinical aggressiveness in CLL. SCF was able to elicit direct biological effects in CLL cells affecting redox homeostasis and cell proliferation. Overall, the aberrantly expressed SCF in CLL cells emerges as a key response regulator to microenvironmental stimuli whilst correlating with poor prognosis. On these grounds, specific targeting of this inflammatory molecule could serve as a novel therapeutic approach in CLL

Novel mutation of the PRNP gene of a clinical CJD case

BACKGROUND: Transmissible spongiform encephalopathies (TSEs), a group of neurodegenerative diseases, are thought to be caused by an abnormal isoform of a naturally occurring protein known as cellular prion protein, PrP(C). The abnormal form of prion protein, PrP(Sc )accumulates in the brain of affected individuals. Both isoforms are encoded by the same prion protein gene (PRNP), and the structural changes occur post-translationally. Certain mutations in the PRNP gene result in genetic TSEs or increased susceptibility to TSEs. CASE PRESENTATION: A 70 year old woman was admitted to the hospital with severe confusion and inability to walk. Relatives recognized memory loss, gait and behavioral disturbances over a six month period prior to hospitalization. Neurological examination revealed Creutzfeldt-Jakob disease (CJD) related symptoms such as incontinence, Babinski sign and myoclonus. EEG showed periodic sharp waves typical of sporadic CJD and cerebrospinal fluid analysis (CSF) was positive for the presence of the 14-3-3-protein. As the disease progressed the patient developed akinetic mutism and died in the tenth month after onset of the disease symptoms. Unfortunately, no autopsy material was available. PRNP sequencing showed the occurrence of a point mutation on one allele at codon 193, which is altered from ACC, coding for a threonine, to ATC, encoding an isoleucine (T193I). CONCLUSION: Here we report a novel mutation of the PRNP gene found in an elderly female patient resulting in heterozygosity for isoleucine and threonine at codon 193, in which normally homozygosity for threonine is expected (T193). The patient presented typical clinical symptoms of CJD. EEG findings and the presence of the 14-3-3 protein in the CSF, contributed to CJD diagnosis, allowing the classification of this case as a probable CJD according to the World Health Organization (WHO) accepted criteria

IGLV3-21*01 is an inherited risk factor for CLL through the acquisition of a single-point mutation enabling autonomous BCR signaling

The prognosis of chronic lymphocytic leukemia (CLL) depends on different markers, including cytogenetic aberrations, oncogenic mutations, and mutational status of the immunoglobulin (Ig) heavy-chain variable (IGHV) gene. The number of IGHV mutations distinguishes mutated (M) CLL with a markedly superior prognosis from unmutated (UM) CLL cases. In addition, B cell antigen receptor (BCR) stereotypes as defined by IGHV usage and complementarity-determining regions (CDRs) classify ∼30% of CLL cases into prognostically important subsets. Subset 2 expresses a BCR with the combination of IGHV3-21-derived heavy chains (HCs) with IGLV3-21-derived light chains (LCs), and is associated with an unfavorable prognosis. Importantly, the subset 2 LC carries a single-point mutation, termed R110, at the junction between the variable and constant LC regions. By analyzing 4 independent clinical cohorts through BCR sequencing and by immunophenotyping with antibodies specifically recognizing wild-type IGLV3-21 and R110-mutated IGLV3-21 (IGLV3-21R110), we show that IGLV3-21R110-expressing CLL represents a distinct subset with poor prognosis independent of IGHV mutations. Compared with other alleles, only IGLV3-21*01 facilitates effective homotypic BCR-BCR interaction that results in autonomous, oncogenic BCR signaling after acquiring R110 as a single-point mutation. Presumably, this mutation acts as a standalone driver that transforms IGLV3-21*01-expressing B cells to develop CLL. Thus, we propose to expand the conventional definition of CLL subset 2 to subset 2L by including all IGLV3-21R110-expressing CLL cases regardless of IGHV mutational status. Moreover, the generation of monoclonal antibodies recognizing IGLV3-21 or mutated IGLV3-21R110 facilitates the recognition of B cells carrying this mutation in CLL patients or healthy donors