INTRODUCTION: The efficacy of anti-CD20 antibodies has significantly contributed to advancing our understanding of disease pathogenesis and improved treatment outcomes in relapsing-remitting multiple sclerosis (RRMS). A comprehensive analysis of the peripheral immune cell profile, combined with prospective clinical characterization, of RRMS patients treated with ocrelizumab (OCR) or ofatumumab (OFA) was performed to further understand immune reconstitution following B-cell depletion. METHODS: REBELLION-MS is a longitudinal analysis of RRMS patients treated with either OCR (n = 34) or OFA (n = 25). Analysis of B, T, natural killer (NK) and natural killer T (NKT) cells at baseline, month 1, and 12 was performed by multidimensional flow cytometry. Data were analyzed by conventional gating and unsupervised computational approaches. In parallel, different clinical parameters were longitudinally assessed. Twenty treatment-naïve age/sex-matched RRMS patients were included as the control cohort. RESULTS: B-cell depletion by OCR and OFA resulted in significant reductions in CD20+ T and B cells as well as B-cell subsets, alongside an expansion of CD5+CD19+CD20- B cells, while also elevating exhaustion markers (CTLA-4, PD-1, TIGIT, TIM-3) across T, B, NK, and NKT cells. Additionally, regulatory T-cell (TREG) numbers increased, especially in OCR-treated patients, and reductions in double-negative (CD3+CD4-CD8-) T cells (DN T cells) were observed, with these DN T cells having higher CD20 expression compared to CD4 or CD8 positive T cells. These immune profile changes correlated with clinical parameters, suggesting pathophysiological relevance in RRMS. CONCLUSIONS: Our interim data add weight to the argumentation that the exhaustion/activation markers, notably TIGIT, may be relevant to the pathogenesis of MS. In addition, we identify a potentially interesting increase in the expression of CD5+ on B cells. Finally, we identified a population of double-negative T cells (KLRG1+HLADR+, in particular) that is associated with MS activity and decreased with CD20 depletion.

• Klíčová slova
• autoimmunity, immune reconstitution, multiple sclerosis, ocrelizumab, ofatumumab,
• MeSH
• antigeny CD20 * imunologie   MeSH
• B-lymfocyty imunologie   účinky léků   MeSH
• buňky NK imunologie   MeSH
• dospělí MeSH
• humanizované monoklonální protilátky * terapeutické užití   farmakologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• longitudinální studie MeSH
• relabující-remitující roztroušená skleróza * imunologie   farmakoterapie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny CD20 * MeSH
• humanizované monoklonální protilátky * MeSH
• ocrelizumab MeSH Prohlížeč
• ofatumumab MeSH Prohlížeč

Rituximab (RTX) plus chemotherapy (R-CHOP) applied as a first-line therapy for lymphoma leads to a relapse in approximately 40% of the patients. Therefore, novel approaches to treat aggressive lymphomas are being intensively investigated. Several RTX-resistant (RR) cell lines have been established as surrogate models to study resistance to R-CHOP. Our study reveals that RR cells are characterized by a major downregulation of CD37, a molecule currently explored as a target for immunotherapy. Using CD20 knockout (KO) cell lines, we demonstrate that CD20 and CD37 form a complex, and hypothesize that the presence of CD20 stabilizes CD37 in the cell membrane. Consequently, we observe a diminished cytotoxicity of anti-CD37 monoclonal antibody (mAb) in complement-dependent cytotoxicity in both RR and CD20 KO cells that can be partially restored upon lysosome inhibition. On the other hand, the internalization rate of anti-CD37 mAb in CD20 KO cells is increased when compared to controls, suggesting unhampered efficacy of antibody drug conjugates (ADCs). Importantly, even a major downregulation in CD37 levels does not hamper the efficacy of CD37-directed chimeric antigen receptor (CAR) T cells. In summary, we present here a novel mechanism of CD37 regulation with further implications for the use of anti-CD37 immunotherapies.

• Klíčová slova
• B-cell lymphoma, CAR T-cells, CD20, CD37, immunotherapy, rituximab,
• MeSH
• antigeny CD20 * imunologie   metabolismus   genetika   MeSH
• antigeny nádorové imunologie   genetika   MeSH
• B-buněčný lymfom * imunologie   terapie   genetika   farmakoterapie   MeSH
• chemorezistence účinky léků   MeSH
• chimerické antigenní receptory imunologie   genetika   metabolismus   MeSH
• cyklofosfamid farmakologie   terapeutické užití   MeSH
• doxorubicin farmakologie   aplikace a dávkování   MeSH
• imunoterapie * metody   MeSH
• lidé MeSH
• monoklonální protilátky farmakologie   terapeutické užití   MeSH
• nádorové buněčné linie MeSH
• protokoly protinádorové kombinované chemoterapie farmakologie   terapeutické užití   MeSH
• regulace genové exprese u nádorů MeSH
• rituximab * farmakologie   terapeutické užití   MeSH
• tetraspaniny * genetika   metabolismus   MeSH
• vinkristin farmakologie   terapeutické užití   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antigeny CD20 * MeSH
• antigeny nádorové MeSH
• CD37 protein, human MeSH Prohlížeč
• chimerické antigenní receptory MeSH
• cyklofosfamid MeSH
• doxorubicin MeSH
• monoklonální protilátky MeSH
• rituximab * MeSH
• tetraspaniny * MeSH
• vinkristin MeSH

A comparative canine-human therapeutics model is being developed in B-cell lymphoma through the generation of a hybridoma cell that produces a murine monoclonal antibody specific for canine CD20. The hybridoma cell produces two light chains, light chain-3, and light chain-7. However, the contribution of either light chain to the authentic full-length hybridoma derived IgG is undefined. Mass spectrometry was used to identify only one of the two light chains, light chain-7, as predominating in the full-length IgG. Gene synthesis created a recombinant murine-canine chimeric monoclonal antibody expressing light chain-7 that reconstituted the IgG binding to CD20. Using light chain-7 as a reference sequence, hydrogen deuterium exchange mass spectrometry was used to identify the dominant CDR region implicated in CD20 antigen binding. Early in the deuteration reaction, the CD20 antigen suppressed deuteration at CDR3 (VH). In later time points, deuterium suppression occurred at CDR2 (VH) and CDR2 (VL), with the maintenance of the CDR3 (VH) interaction. These data suggest that CDR3 (VH) functions as the dominant antigen docking motif and that antibody aggregation is induced at later time points after antigen binding. These approaches define a methodology for fine mapping of CDR contacts using nested enzymatic reactions and hydrogen deuterium exchange mass spectrometry. These data support the further development of an engineered, synthetic canine-murine monoclonal antibody, focused on CDR3 (VH), for use as a canine lymphoma therapeutic that mimics the human-murine chimeric anti-CD20 antibody Rituximab.

• Klíčová slova
• CD20, comparative medicine, hydrogen deuterium exchange mass spectrometry, lymphoma, monoclonal antibody,
• MeSH
• antigeny CD20 imunologie   MeSH
• chromatografie kapalinová MeSH
• imunoglobulin G chemie   MeSH
• kinetika MeSH
• lehké řetězce imunoglobulinů genetika   metabolismus   MeSH
• lidé MeSH
• monoklonální protilátky chemie   genetika   MeSH
• nádorové buněčné linie MeSH
• peptidová knihovna MeSH
• psi MeSH
• rekombinantní fúzní proteiny MeSH
• sekvence aminokyselin MeSH
• tandemová hmotnostní spektrometrie MeSH
• těžké řetězce imunoglobulinů genetika   metabolismus   MeSH
• vazebná místa protilátek MeSH
• vodík/deuteriová výměna a hmotnostní spektrometrie * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• psi MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny CD20 MeSH
• imunoglobulin G MeSH
• lehké řetězce imunoglobulinů MeSH
• monoklonální protilátky MeSH
• peptidová knihovna MeSH
• rekombinantní fúzní proteiny MeSH
• těžké řetězce imunoglobulinů MeSH

Ocrelizumab, rituximab, ofatumumab, ublituximab, inebilizumab, and evobrutinib are immunotherapies that target various B cell-related proteins. Most of these treatments have proven efficacy in relapsing and progressive forms of MS and neuromyelitis optica spectrum disease (NMOSD), or are in advanced stages of clinical development. Currently, ocrelizumab, ofatumumab, and inebilizumab are licensed for treatment of MS and NMOSD, respectively. This review focuses on the current state of knowledge about the role of B lymphocytes in immune-mediated pathophysiology and its implications for the mode of action. To understand the significance of this breakthrough in the context of the current MS therapeutic armamentarium, this review more closely examines the clinical development of CD20 depletion and the pioneering contribution of rituximab. Phase 3 and the recently published postmarketing studies will be highlighted to better understand the relevant efficacy data and safety aspects of long-term B-cell depletion.

• MeSH
• antigeny CD20 účinky léků   imunologie   MeSH
• B-lymfocyty účinky léků   imunologie   MeSH
• imunologické faktory farmakologie   MeSH
• lidé MeSH
• neuromyelitis optica farmakoterapie   imunologie   MeSH
• roztroušená skleróza farmakoterapie   imunologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• antigeny CD20 MeSH
• imunologické faktory MeSH

BACKGROUND: Several European countries recently developed international diagnostic and management guidelines for pemphigus, which have been instrumental in the standardization of pemphigus management. OBJECTIVE: We now present results from a subsequent Delphi consensus to broaden the generalizability of the recommendations. METHODS: A preliminary survey, based on the European Dermatology Forum and the European Academy of Dermatology and Venereology guidelines, was sent to a panel of international experts to determine the level of consensus. The results were discussed at the International Bullous Diseases Consensus Group in March 2016 during the annual American Academy of Dermatology conference. Following the meeting, a second survey was sent to more experts to achieve greater international consensus. RESULTS: The 39 experts participated in the first round of the Delphi survey, and 54 experts from 21 countries completed the second round. The number of statements in the survey was reduced from 175 topics in Delphi I to 24 topics in Delphi II on the basis of Delphi results and meeting discussion. LIMITATIONS: Each recommendation represents the majority opinion and therefore may not reflect all possible treatment options available. CONCLUSIONS: We present here the recommendations resulting from this Delphi process. This international consensus includes intravenous CD20 inhibitors as a first-line therapy option for moderate-to-severe pemphigus.

• Klíčová slova
• CD20 inhibitor, consensus, guidelines, pemphigus foliaceus, pemphigus vulgaris, treatment,
• MeSH
• akademie a ústavy normy   MeSH
• antigeny CD20 imunologie   MeSH
• delfská metoda MeSH
• dermatologie metody   normy   MeSH
• glukokortikoidy aplikace a dávkování   MeSH
• imunologické faktory aplikace a dávkování   MeSH
• intravenózní podání MeSH
• kombinovaná farmakoterapie metody   normy   MeSH
• kombinovaná terapie metody   normy   MeSH
• konsensus MeSH
• lidé MeSH
• pemfigus diagnóza   imunologie   terapie   MeSH
• plazmaferéza * MeSH
• rituximab aplikace a dávkování   MeSH
• směrnice pro lékařskou praxi jako téma * MeSH
• stupeň závažnosti nemoci MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Evropa MeSH
• Názvy látek
• antigeny CD20 MeSH
• glukokortikoidy MeSH
• imunologické faktory MeSH
• rituximab MeSH

Monoclonal antibodies are leading agents for therapeutic treatment of human diseases, but are limited in use by the paucity of clinically relevant models for validation. Sporadic canine tumours mimic the features of some human equivalents. Developing canine immunotherapeutics can be an approach for modeling human disease responses. Rituximab is a pioneering agent used to treat human hematological malignancies. Biologic mimics that target canine CD20 are just being developed by the biotechnology industry. Towards a comparative canine-human model system, we have developed a novel anti-CD20 monoclonal antibody (NCD1.2) that binds both human and canine CD20. NCD1.2 has a sub-nanomolar Kd as defined by an octet red binding assay. Using FACS, NCD1.2 binds to clinically derived canine cells including B-cells in peripheral blood and in different histotypes of B-cell lymphoma. Immunohistochemical staining of canine tissues indicates that the NCD1.2 binds to membrane localized cells in Diffuse Large B-cell lymphoma, Marginal Zone Lymphoma, and other canine B-cell lymphomas. We cloned the heavy and light chains of NCD1.2 from hybridomas to determine whether active scaffolds can be acquired as future biologics tools. The VH and VL genes from the hybridomas were cloned using degenerate primers and packaged as single chains (scFv) into a phage-display library. Surprisingly, we identified two scFv (scFv-3 and scFv-7) isolated from the hybridoma with bioactivity towards CD20. The two scFv had identical VH genes but different VL genes and identical CDR3s, indicating that at least two light chain mRNAs are encoded by NCD1.2 hybridoma cells. Both scFv-3 and scFv-7 were cloned into mammalian vectors for secretion in CHO cells and the antibodies were bioactive towards recombinant CD20 protein or peptide. The scFv-3 and scFv-7 were cloned into an ADEPT-CPG2 bioconjugate vector where bioactivity was retained when expressed in bacterial systems. These data identify a recombinant anti-CD20 scFv that might form a useful tool for evaluation in bioconjugate-directed anti-CD20 immunotherapies in comparative medicine.

• MeSH
• antigeny CD20 * chemie   genetika   imunologie   metabolismus   MeSH
• buněčné linie MeSH
• epitopy imunologie   MeSH
• exprese genu MeSH
• hybridomy imunologie   metabolismus   MeSH
• jednořetězcové protilátky imunologie   farmakologie   MeSH
• klonování DNA MeSH
• lehké řetězce imunoglobulinů genetika   MeSH
• lidé MeSH
• molekulární sekvence - údaje MeSH
• myši MeSH
• peptidová knihovna MeSH
• peptidy chemie   metabolismus   MeSH
• psi MeSH
• rekombinantní fúzní proteiny farmakologie   MeSH
• sekvence aminokyselin MeSH
• sekvenční seřazení MeSH
• specificita protilátek imunologie   MeSH
• těžké řetězce imunoglobulinů genetika   MeSH
• tvorba protilátek imunologie   MeSH
• vazba proteinů imunologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• psi MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny CD20 * MeSH
• epitopy MeSH
• jednořetězcové protilátky MeSH
• lehké řetězce imunoglobulinů MeSH
• peptidová knihovna MeSH
• peptidy MeSH
• rekombinantní fúzní proteiny MeSH
• těžké řetězce imunoglobulinů MeSH

Abnormalities in ATM and TP53 genes represent important predictive factors in chronic lymphocytic leukemia (CLL); however, the efficacy of CD20 targeting immunotherapy is only poorly defined in the affected patients. Therefore, we tested the in vitro response to ofatumumab (OFA) and rituximab (RTX) in 75 CLL samples with clearly defined p53 or ATM inactivation. Using standard conditions allowing complement-dependent cytotoxicity, i.e., 10 μg/mL of antibodies and 20% active human serum, we observed clear differences among the tested genetic categories: ATM-mutated samples (n = 17) represented the most sensitive, wild-type samples (n = 31) intermediate, and TP53-mutated samples (n = 27) the most resistant group (ATM-mut vs. TP53-mut: P = 0.0005 for OFA and P = 0.01 for RTX). The response correlated with distinct levels of CD20 and critical complement inhibitors CD55 and CD59; CD20 level median was the highest in ATM-mutated and the lowest in TP53-mutated samples (difference between the groups P < 0.01), while the total level of complement inhibitors (CD55 plus CD59) was distributed in the opposite manner (P < 0.01). Negligible response to both OFA and RTX was noted in all cultures (n = 10) tested in the absence of active serum, which strongly indicated that complement-dependent cytotoxicity was a principal cell death mechanism. Our study shows that (1) common genetic defects in CLL cells significantly impact a primary response to anti-CD20 monoclonal antibodies and (2) ATM-mutated patients with currently poor prognosis may potentially benefit from immunotherapy targeting CD20.

• MeSH
• antigeny CD20 účinky léků   imunologie   MeSH
• antigeny CD55 imunologie   MeSH
• antigeny CD59 imunologie   MeSH
• antigeny nádorové účinky léků   imunologie   MeSH
• ATM protein nedostatek   genetika   fyziologie   MeSH
• chemorezistence MeSH
• chronická lymfatická leukemie patologie   MeSH
• dospělí MeSH
• geny p53 * MeSH
• humanizované monoklonální protilátky MeSH
• komplement imunologie   MeSH
• kultivační média MeSH
• lidé středního věku MeSH
• lidé MeSH
• monoklonální protilátky farmakologie   MeSH
• myší monoklonální protilátky farmakologie   MeSH
• nádorové buňky kultivované MeSH
• nádorové proteiny genetika   MeSH
• nádorový supresorový protein p53 nedostatek   fyziologie   MeSH
• oprava DNA genetika   MeSH
• rituximab MeSH
• screeningové testy protinádorových léčiv MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• sérum MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• antigeny CD20 MeSH
• antigeny CD55 MeSH
• antigeny CD59 MeSH
• antigeny nádorové MeSH
• ATM protein, human MeSH Prohlížeč
• ATM protein MeSH
• CD59 protein, human MeSH Prohlížeč
• humanizované monoklonální protilátky MeSH
• komplement MeSH
• kultivační média MeSH
• monoklonální protilátky MeSH
• myší monoklonální protilátky MeSH
• nádorové proteiny MeSH
• nádorový supresorový protein p53 MeSH
• ofatumumab MeSH Prohlížeč
• rituximab MeSH
• TP53 protein, human MeSH Prohlížeč

OBJECTIVES: We present the first study to explore safety and efficacy of the human CD20 monoclonal antibody ofatumumab in relapsing-remitting multiple sclerosis (RRMS). METHODS: In this randomized, double-blind, placebo-controlled study, patients received 2 ofatumumab infusions (100 mg, 300 mg, or 700 mg) or placebo 2 weeks apart. At week 24, patients received alternate treatment. Safety and efficacy were assessed. RESULTS: Thirty-eight patients were randomized (ofatumumab/placebo, n = 26; placebo/ofatumumab, n = 12) and analyzed; 36 completed the study. Two patients in the 300-mg group withdrew from the study because of adverse events. No unexpected safety signals emerged. Infusion-related reactions were common on the first infusion day but not observed on the second infusion day. None of the patients developed human anti-human antibodies. Ofatumumab was associated with profound selective reduction of B cells as measured by CD19(+) expression. New brain MRI lesion activity was suppressed (>99%) in the first 24 weeks after ofatumumab administration (all doses), with statistically significant reductions (p < 0.001) favoring ofatumumab found in new T1 gadolinium-enhancing lesions, total enhancing T1 lesions, and new and/or enlarging T2 lesions. CONCLUSIONS: Ofatumumab (up to 700 mg) given 2 weeks apart was not associated with any unexpected safety concerns and was well tolerated in patients with RRMS. MRI data suggest a clinically meaningful effect of ofatumumab for all doses studied. Results warrant further exploration of ofatumumab in RRMS. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that in patients with RRMS, ofatumumab compared with placebo does not increase the number of serious adverse events and decreases the number of new MRI lesions.

• MeSH
• antigeny CD19 biosyntéza   imunologie   MeSH
• antigeny CD20 aplikace a dávkování   škodlivé účinky   imunologie   MeSH
• dospělí MeSH
• dvojitá slepá metoda MeSH
• humanizované monoklonální protilátky MeSH
• lidé středního věku MeSH
• lidé MeSH
• medicína založená na důkazech metody   trendy   MeSH
• mladý dospělý MeSH
• monoklonální protilátky aplikace a dávkování   škodlivé účinky   terapeutické užití   MeSH
• relabující-remitující roztroušená skleróza krev   farmakoterapie   imunologie   MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• klinické zkoušky, fáze II MeSH
• multicentrická studie MeSH
• práce podpořená grantem MeSH
• randomizované kontrolované studie MeSH
• Názvy látek
• antigeny CD19 MeSH
• antigeny CD20 MeSH
• humanizované monoklonální protilátky MeSH
• monoklonální protilátky MeSH
• ofatumumab MeSH Prohlížeč

• MeSH
• antigeny CD20 imunologie   MeSH
• folikulární lymfom farmakoterapie   genetika   MeSH
• geny bcl-2 genetika   MeSH
• geny pro těžké řetězce imunoglobulinů genetika   MeSH
• indukce remise MeSH
• lidé MeSH
• monoklonální protilátky terapeutické užití   MeSH
• myší monoklonální protilátky MeSH
• prognóza MeSH
• protinádorové látky terapeutické užití   MeSH
• rituximab MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• komentáře MeSH
• úvodníky MeSH
• Názvy látek
• antigeny CD20 MeSH
• monoklonální protilátky MeSH
• myší monoklonální protilátky MeSH
• protinádorové látky MeSH
• rituximab MeSH