CD19 Cell Count at Baseline Predicts B Cell Repopulation at 6 and 12 Months in Multiple Sclerosis Patients Treated with Ocrelizumab

Background: The kinetics of B cell repopulation in MS patients treated with Ocrelizumab is highly variable, suggesting that a fixed dosage and time scheduling might be not optimal. We aimed to investigate whether B cell repopulation kinetics influences clinical and radiological outcomes and whether circulating immune asset at baseline affects B cell repopulation kinetics. Methods: 218 MS patients treated with Ocrelizumab were included. Every six months we collected data on clinical and magnetic resonance imaging (MRI) activity and lymphocyte subsets at baseline. According to B cell counts at six and twelve months, we identified two groups of patients, those with fast repopulation rate (FR) and those with slow repopulation rate (SR). Results: A significant reduction in clinical and radiological activity was found. One hundred fifty-five patients had complete data and received at least three treatment cycles (twelve-month follow-up). After six months, the FR patients were 41/155 (26.45%) and 10/41 (29.27%) remained non-depleted after twelve months. FR patients showed a significantly higher percentage of active MRI scan at twelve months (17.39% vs. 2.53%; p = 0,008). Furthermore, FR patients had a higher baseline B cell count compared to patients with an SR (p = 0.02 and p = 0.002, at the six- and twelve-month follow-ups, respectively). Conclusion: A considerable proportion of MS patients did not achieve a complete CD19 cell depletion and these patients had a higher baseline CD19 cell count. These findings, together with the higher MRI activity found in FR patients, suggest that the Ocrelizumab dosage could be tailored depending on CD19 cell counts at baseline in order to achieve complete disease control in all patients

COVID-19 Severity in Multiple Sclerosis: Putting Data Into Context

Background and objectives: It is unclear how multiple sclerosis (MS) affects the severity of COVID-19. The aim of this study is to compare COVID-19-related outcomes collected in an Italian cohort of patients with MS with the outcomes expected in the age- and sex-matched Italian population. Methods: Hospitalization, intensive care unit (ICU) admission, and death after COVID-19 diagnosis of 1,362 patients with MS were compared with the age- and sex-matched Italian population in a retrospective observational case-cohort study with population-based control. The observed vs the expected events were compared in the whole MS cohort and in different subgroups (higher risk: Expanded Disability Status Scale [EDSS] score > 3 or at least 1 comorbidity, lower risk: EDSS score ≤ 3 and no comorbidities) by the χ2 test, and the risk excess was quantified by risk ratios (RRs). Results: The risk of severe events was about twice the risk in the age- and sex-matched Italian population: RR = 2.12 for hospitalization (p < 0.001), RR = 2.19 for ICU admission (p < 0.001), and RR = 2.43 for death (p < 0.001). The excess of risk was confined to the higher-risk group (n = 553). In lower-risk patients (n = 809), the rate of events was close to that of the Italian age- and sex-matched population (RR = 1.12 for hospitalization, RR = 1.52 for ICU admission, and RR = 1.19 for death). In the lower-risk group, an increased hospitalization risk was detected in patients on anti-CD20 (RR = 3.03, p = 0.005), whereas a decrease was detected in patients on interferon (0 observed vs 4 expected events, p = 0.04). Discussion: Overall, the MS cohort had a risk of severe events that is twice the risk than the age- and sex-matched Italian population. This excess of risk is mainly explained by the EDSS score and comorbidities, whereas a residual increase of hospitalization risk was observed in patients on anti-CD20 therapies and a decrease in people on interferon

DMTs and Covid-19 severity in MS: a pooled analysis from Italy and France

We evaluated the effect of DMTs on Covid-19 severity in patients with MS, with a pooled-analysis of two large cohorts from Italy and France. The association of baseline characteristics and DMTs with Covid-19 severity was assessed by multivariate ordinal-logistic models and pooled by a fixed-effect meta-analysis. 1066 patients with MS from Italy and 721 from France were included. In the multivariate model, anti-CD20 therapies were significantly associated (OR = 2.05, 95%CI = 1.39–3.02, p < 0.001) with Covid-19 severity, whereas interferon indicated a decreased risk (OR = 0.42, 95%CI = 0.18–0.99, p = 0.047). This pooled-analysis confirms an increased risk of severe Covid-19 in patients on anti-CD20 therapies and supports the protective role of interferon

Studio del ruolo del fattore del PDGF-B nello sviluppo embrionale e nella tumorigenesi mediante l'uso di embrioni di Xenopus laevis

La famiglia del fattore di crescita derivato dalle piastrine PDGF è costituita da due recettori (α e β) e quattro ligandi (A, B, C, D), in grado di formare omodimeri e l’eterodimero AB che svolgono diversi ruoli sia durante lo sviluppo che nella vita adulta dei vertebrati. In particolare, un’alterata espressione del PDGF-B è comunemente riscontrata negli oligodendrogliomi un gruppo eterogeneo di tumori cerebrali altamente aggressivi e pressoché incurabili. Studi recenti hanno dimostrato che la sola sovraespressione del PDGF-B in progenitori neurali embrionali di topo è in grado di indurre oligodendrogliomi. Come modello di studio alternativo, ho utilizzato le cellule delle creste neurali (NCC) di embrioni di Xenopus laevis, data la loro affinità alle cellule cancerose in termini di transizione epitelio-mesenchimatica, invasività e migrazione a lunga distanza. Esperimenti preliminari di sovraespressione genica, per il hPDGF-B, hanno dimostrato che tale fattore è in grado di alterare il comportamento delle NCC alterandone la segregazione e migrazione. Questo correla con l’ipotizzato coinvolgimento del PDGF-B nella progressione tumorale, in particolare nella motilità e nell’invasività cellulare ma di cui sono ad oggi ancora poco noti i meccanismi molecolari e cellulari. Un’altra via di segnalazione nota per essere alterata nei gliomi e nel regolare il comportamento migratorio delle NCC è quella nota come “Planar Cell Polarity Pathway” (PCP) che coinvolge membri della famiglia dei Wnts. Il primo scopo della mia tesi è stato quindi quello di valutare una possibile interazione funzionale tra la via di segnalazione del PDGF-B e la via PCP. Per questa analisi ho effettutato co-iniezioni dell’mRNA per hPDGF-B e per specifici modulatori (attivatori o inibitori) della via PCP in embrioni di Xenopus su cui poi è stata valutata la migrazione delle NCC. Parallelamente ho contribuito a definitre il pattern di espressione genica del Pdgf-b durante l’embriogenesi di Xenopus laevis andandone a valutare anche un possibile ruolo durante lo sviluppo delle NCC. A questo scopo sto conducendo esperimenti di perdita di funzione genica tramite microiniezione di uno “splicing Morpholino” per il Pdgf-b di Xenopus. I risultati ottenuti suggeriscono che l’attivazione della via del PDGF-B possa inibire il la via di segnalazione attivata dal PCP. I miei dati, seppur preliminari, possono suggerire inoltre un possibile ruolo della via di segnalazione del PDGF-B anche durante lo sviluppo embrionale ed in particolare nel regolare la migrazione delle creste neurali

Induction of leukemic myeloid progenitor cell death by a combination of ER and oxidative stress

The clonal expansion of hematopoietic myeloid precursors blocked at different stages of differentiation characterizes the acute myeloid leukemia (AML) phenotype characterized by the expression of fusion or mutant proteins that cause impaired differentiation and enhanced proliferation and survival. We previously showed that APL cell lines and primary blasts induced to differentiate by RA become highly sensitive to amounts of ER stress not detrimental for the same cells in the absence of Retinoic Acid (RA) (1). Furthermore the same cells resulted sensitive to a combination of ER stress inducers with Arsenic Trioxide (ATO) that generates oxidative stress. Importantly we observed that ER stress caused increased amounts of disulphide-bound high molecular weight aggregates of PML-RARα and PML, exacerbating the alteration of cellular proteostasis already generated by induction of ER stress. This observation provides the rationale to translate the findings we observed in APL to other types of AML characterized by fusion or mutant proteins. The presence of mutant proteins that are easily prone to aggregation or mis-folding, because of their mutant structure or because of mis-localization, could render the cells sensitive to levels of ER and oxidative stress that could be recovered in their absence. We first tested a panel of AML cell lines characterized by different oncogenic fusion or mutant proteins and we found that ML-2 cells, bearing the MLL-AF6 fusion protein, and MV-4-11 cells, expressing the fusion protein MLL-AF4 and FLT3-ITD are highly sensitive to the combination of sub-lethal amounts of RA, Tm and ATO. In the cells undergoing ER and oxidative stress in combination, we found prolonged activation of the antioxidant response and of the unfolded protein response (UPR), activated by ER stress, as indicated by the expression of HMOX, CHOP, BiP and sXBP1. Importantly, the combination of ER and oxidative stress significantly reduces the colony forming capacity of primary leukemic blasts isolated from the bone marrow of FLT3-ITD positive patients. Altogether our data suggest that the combination of ER and oxidative stress leads to apoptosis rather than recovery, achieved instead when the same stresses are induced alone

Lymphopenia in Multiple Sclerosis patients treated with Ocrelizumab is associated with an effect on CD8 T cells

Background: In the phase III, OPERA I and OPERA II, clinical trial lymphopenia was reported in 20.7% of relapsing-remitting multiple sclerosis (RRMS) patients taking Ocrelizumab (OCR). Objective: The objective of this study was to investigate the effect of OCR on lymphocyte subtypes in MS patients with and without lymphopenia. Methods: Retrospective study comparing lymphocyte subtypes in OCR-treated MS patients with low (G1) and normal (G2) absolute lymphocyte count (ALC) at the six-month follow-up (cut-off: 1000 × 106/L). Mann Whitney U test was used to compare ALC, CD19, CD4 T, CD8 T and NK cell counts at baseline and at the six-month follow up between the two groups. A linear mixed model was applied to compare changes in ALC, and subset counts and proportions between patients with and without lymphopenia. We performed the same analyses in a subpopulation of naïve to treatment patients to exclude the possible influence of the previous disease modifying therapy (DMT) in the different kinetics observed between the two groups. Results: One hundred sixty-seven patients were included (G1, n = 34; G2, n = 133). At the six-month follow-up, compared with baseline, in the whole population we observed a significant reduction in ALC (p<0.0001), CD19 (p<0.0001) and CD8 T (p<0.0288) lymphocytes. We also found and increase in CD4/CD8 ratio after six months of treatment (p = 0.0098). G1 showed a lower ALC than G2 at baseline. At six months, mean ALC was 896.41 ± 156.25 × 106/L in G1 and 1909.9 ± 629.07 × 106/L in G2. CD4 and CD8 T cell mean counts were lower (p < 0.0001) in G1 than G2. At the linear mixed model analysis, we found a more pronounced increase in CD8 T percentage in G2 than G1 (p = 0.008). In the naïve to treatment group fifty patients were included. CD4 and CD8 T cell mean counts at six months were lower (p = 0.0074 and p = 0.0032, respectively) in G1 than G2. At the linear mixed model analysis, we found a more pronounced decrease of CD8 T cell count in G1 than G2 (p = 0.0103). Furthermore, we found an increase in CD8 T percentage in G2 whereas a profound decrease of CD8 T percentage was observed in G1 (p = 0.0052). After adjusting for confounders, significantly positive correlations were noted between ALC and both CD4 and CD8 T cell counts. Negative correlation was observed between ALC and CD4/CD8 ratio driven by low CD8 T cell counts. Conclusion: OCR decreases ALC. Among T cells, the treatment predominantly impacts CD8 cells. However, CD8 T cell decrease was more pronounced in patients with lymphopenia. Further studies are needed to establish the relationship between the effect of OCR on ALC and CD8 T cells and its potential implication in the early clinical response and risk for viral infections

Impact of early diagnosis on clinical characteristics of an Italian sample of people with multiple sclerosis recruited online

Background: In order to anticipate the diagnosis of Multiple Sclerosis (MS), the diagnostic criteria had been reviewed several times in the last years. Objective: We wanted to understand whether earlier diagnoses of MS have impacted on therapeutic management of the disease. Methods: We designed a 22-item survey posted on SMsocialnetwork, a webplatform with a medical supervision, dedicated to Italian MS patients. We collected socio-demographic data, disease and treatment-related information of 1000 patients. Results: The median age at diagnosis significantly decreased over years. In the last decades the time delay between disease onset and diagnosis reduced, the disease phenotypes at diagnosis shifted from progressive form to relapsing ones and clinically isolated syndrome, the number of early treated patients increased over time. Conclusion: We showed, verifying a large sample of patients in a reallife setting, that the improvement of the diagnostic process allowed the anticipation of MS diagnosis over years and had a huge impact in terms of treatment approach

Previous disease-modifying treatments influence T lymphocyte kinetics in people with multiple sclerosis switching to ocrelizumab

Background: Recently, concern has been raised about the influence of the previous disease-modifying treatments (DMTs) on the clinical efficacy of ocrelizumab (OCR). We aimed to evaluate whether the previous DMT affects the lymphocyte subset kinetics in people with Multiple Sclerosis (MS) switching to OCR.Methods: This is a multicenter, retrospective, real-world study on consecutive MS patients who started or switched to OCR. We grouped them by prior DMT in: (i) naive-to-treatment (NTT), (ii) switching from fingolimod (SF) and (iii) switching from natalizumab (SN). Differences in absolute lymphocyte count and lymphocyte subset count changes, considering the period from baseline to 6 months, over all the three groups were assessed with an inverse-probability-weighted regression adjustment model.Results: Mean T CD4+ cell count reduction from baseline to the six-month follow-up was more pronounced in the SN group compared to the NTT (p = 0,026). Further, patients in the SF group experienced a less pronounced CD4 T cell number decrease than both NTT and SN groups (p = 0,04 and p < 0,001, respectively). Patients in the SF group experienced an increase in CD8 T cell absolute number, whereas those in the NTT and SN groups expe-rienced a significant decrease (p = 0,015 andp < 0,001, respectively). Patients experiencing early inflammatory activity showed a lower CD8+ cell count at baseline than stable patients (p = 0,02).Conclusions: Previous DMTs influence the lymphocyte kinetics in people with MS switching to OCR. Reassessment of these findings over a larger population may help optimize the switch