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1.
Clinical Immunology ; Conference: 2023 Clinical Immunology Society Annual Meeting: Immune Deficiency and Dysregulation North American Conference. St. Louis United States. 250(Supplement) (no pagination), 2023.
Article in English | EMBASE | ID: covidwho-20240620

ABSTRACT

RAG mutations cause various phenotypes: SCID, Omenn syndrome (OS), leaky SCID (LS) and combined immunodeficiency (CID). We had previously reported autoantibodies targeting IFN-alpha, IFN-omega in patients with RAG deficiency. However, how the presence of such antibodies correlated with the severity of the clinical phenotype and with the recombination activity of the mutant proteins was unknown. To address this, we have studied anti-cytokine antibodies in 118 patients with RAG defects (SCID, n = 28;OS, n = 29;LS, n = 29;CID, n = 32), and in 42 controls (protocols NCT03394053 and NCT03610802). RAG mutant proteins associated with CID and LS retained 35.6 +/- 4.3 (mean +/- SE) and 29.8 +/- 5.1% recombination activity respectively, compared to wildtype protein, which was significantly higher than the recombination activity of the mutant RAG proteins associated with OS (4.1 +/- 1.5%) and SCID (5.7 +/- 2.1%) (p < 0.0001). Among 32 CID patients, 24 tested positive for anti-IFN-alpha and 21 for anti-IFN-omega antibodies. Among 29 LS patients, 15 had high levels of anti-IFN-alpha and 13 of anti-IFN-omega antibodies. A minority of the CID and LS patients had also high levels of anti-IFN-beta and anti-IL-22 antibodies. By contrast, none of the OS patients tested positive for anti-cytokine antibodies. High levels of anti-IFN-alpha and anti-IFN-omega antibodies correlated with their neutralizing activity as demonstrated in vitro by analysis of STAT1 phosphorylation upon stimulation of healthy donor monocytes in the presence of the appropriate cytokine and patient's or control plasma. Severe viral infections were recorded in 26/41 patients with CID and LS who tested positive and in 7/20 who tested negative for anti-IFN-alpha and/or anti-IFN-omega antibodies (p <0.05). Among those with anti-IFN antibodies, EBV (n = 8), CMV (n = 6), HSV (n = 5), VZV (n = 4) and adenovirus (n = 4) infections were more common. Two patients had COVID-19, which was fatal in one. Presence of the rubella virus was documented in 5 patients with anti-type I IFN antibodies. These results demonstrate that high levels of neutralizing anti-IFN-alpha and anti-IFN-omega antibodies are common in patients with RAG mutations manifesting as CID and LS, but not in those with OS, and that their presence is associated with a high risk of serious viral infections.Copyright © 2023 Elsevier Inc.

2.
J Allergy Clin Immunol Pract ; 2022 Oct 21.
Article in English | MEDLINE | ID: covidwho-2234577

ABSTRACT

BACKGROUND: The contemporaneous presence of immune defects and heart diseases in patients with 22q11.2 deletion syndrome (22q11.3DS) might represent risk factors for severe coronavirus 2019 disease (COVID-19). OBJECTIVE: To analyze severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outcome in 22q11.2DS patients and immunogenicity of different doses of mRNA SARS-CoV-2 vaccine. METHODS: Longitudinal observational study on SARS-CoV-2 outcome in 60 adults with 22q11.2DS (March 2020-June 2022). Anti-Spike, and anti-receptor binding domain (RBD) antibody responses, generation of Spike-specific memory B cells (MBCs) and Spike-specific T cells at different time points before and after the mRNA BNT162b2 vaccination were evaluated in 16 22q11.2DS patients. RESULTS: We recorded a 95% rate of vaccination, with almost all patients being immunized with the booster dose. Twenty-one patients had SARS-CoV-2 infection. Three patients were infected before vaccine availability, 6 after receiving 2 doses of vaccine, and 12 after one booster dose. The SARS-CoV-2- infection had a mild course, except in one unvaccinated patient with several comorbidities who died from acute respiratory distress syndrome (fatality rate 5%). Infected patients had more frequently moderate/severe intellectual disability, lymphopenia, and lower CD4+ count. Despite major congenital heart diseases, COVID-19 did not impact cardiological conditions. The BNT162b2 vaccine induced S1-immunoglobulin G (IgG) responses, low serum S1-IgA, and slightly impaired specific MBCs response. Specific T-cell responses observed were related to lymphocytes and CD4+ T cell counts. CONCLUSIONS: The SARS-CoV-2 infection had a mild course in most patients with 22q11.2DS, even in patients with major cardiovascular diseases. Immunization induced Spike-specific IgG responses and generated specific MBCs and memory T cells. The weaker memory responses in patients with lymphopenia suggested the need for additional doses.

3.
Cell Chem Biol ; 30(1): 85-96.e6, 2023 Jan 19.
Article in English | MEDLINE | ID: covidwho-2177358

ABSTRACT

As a clinical vaccine, lipid nanoparticle (LNP) mRNA has demonstrated potent and broad antibody responses, leading to speculation about its potential for antibody discovery. Here, we developed RAMIHM, a highly efficient strategy for developing fully human monoclonal antibodies that employs rapid mRNA immunization of humanized mice followed by single B cell sequencing (scBCR-seq). We immunized humanized transgenic mice with RAMIHM and generated 15 top-ranked clones from peripheral blood, plasma B, and memory B cell populations, demonstrating a high rate of antigen-specificity (93.3%). Two Omicron-specific neutralizing antibodies with high potency and one broad-spectrum neutralizing antibody were discovered. Furthermore, we extended the application of RAMIHM to cancer immunotherapy targets, including a single transmembrane protein CD22 and a multi-transmembrane G protein-coupled receptor target, GPRC5D, which is difficult for traditional protein immunization methods. RAMIHM-scBCR-seq is a broadly applicable platform for the rapid and efficient development of fully human monoclonal antibodies against an assortment of targets.


Subject(s)
Antibodies, Monoclonal , Immunization , Mice , Humans , Animals , Antibodies, Monoclonal/genetics , RNA, Messenger/genetics , Vaccination , Antibodies, Neutralizing/genetics , Mice, Transgenic
4.
Hematology, Transfusion and Cell Therapy ; 43:S114-S115, 2021.
Article in English | EMBASE | ID: covidwho-1859599

ABSTRACT

Introdução: A macroglobulinemia de Waldenstrom (MW) é uma patologia linfoproliferativa neoplásica maligna das células plasmáticas e linfócitos B, normalmente responsável pela síntese das cadeias pesadas de imunoglobulinas. Diferente da leucemia linfoblástica aguda, os linfócitos mantêm a capacidade de se diferenciar e amadurecer em células plasmáticas. A MW possui características que variam de células linfoides maduras a plasmócitos. Imunofenotipagem de células obtidas a partir da medula óssea, dos linfonodos ou do sangue periférico de pacientes com essa doença mostram IgM citoplasmática detectável em células plasmáticas e imunoglobulina superficial na maioria dos linfócitos. Objetivo: Apresentar um caso de MW. Material e métodos: Revisão de prontuáriros médicos e literatura. Descrição do caso: Paciente do sexo masculino, 61 anos, apresentou epistaxe de grande volume com repetição, fadiga e astenia, além de perda de 15 quilos em 6 meses. Na admissão hospitalar apresentava os seguintes exames: anemia com hemoglobina 5,4 g/dL, hemácias de 1,45 milhão/mm3, plaquetopenia (87.000/mm3), presença de esplenomegalia importante, roleaux eritrocitário, esplenomegalia e linfonodomegalia abdominal. Solicitada avaliação com hematologista por paciente referir repetidas anemias ao longo da vida e histórico de transfusões de repetição. Seguem os resultados da investigação com especialisgta: Mielograma apresentou células linfoides de tamanho pequeno e aspecto maduro, algumas apresentando aspecto plasmocitoide. Imunofenotipagem de sangue periférico com CD20/CD38, CD38, CD200, CD19/CD200 positivo fraco;CD19, CD45, CD45/CD22, KAPPA, CD20: positivo de alta intensidade;KAPPA cito- plasmático e CD43 positivo. Dosagem de Imunoglobulinas: IgM 10.100 mg/dL, IgG 242 mg/dL e IgA 91,5 mg/dL. Pico monoclonal IgM/Lambda na imunofixação sérica. Exame de Coombs direto negativo. Como terapêutica, iniciou-se Ciclofosfamida associado a Rituximabe. O paciente evoluiu ao óbito devido ao Covid-19 durante a internação. Discussão: A MW é uma neoplasia rara, sendo que o paciente deste relato enquadra-se na idade média do diagnóstico de MW, que ocorre em torno dos 60 anos, maioria do sexo masculino. Grande parte dos pacientes apresenta sintomas como fadiga, fraqueza e sangramento (principalmente epistaxe). Outras manifestações como perda de peso, distúrbios visuais e fenômeno de Raynaud são menos comuns. Ao exame físico, encontra-se rotineiramente hepatoesplenomegalia e linfadenopatia. Proteinúria de Bence Jones está presente em um quarto de todos os pacientes com MW, devido a uma lesão predominantemente glomerular com depósitos de IgM e material amiloide. A função plaquetária está prejudicada pelo revestimento de plaquetas com IgM, e alguns pacientes podem apresentar defeitos da cascata de coagulação. Os níveis de IgM são marcadamente aumentados, e a crioglobulina pode ser detectada em alguns pacientes. O tratamento deve ser individualizado de acordo com as manifestações clínicas de cada paciente e seu curso clínico é variável. Causas de morte relacionam-se geralmente a hiperviscosidade, anemia, hemorragia, trombose e infecções, sendo que neste caso a infecção por Covid-19 atuou como fator definidor. Conclusão: É oportuno o relato de um caso de MW devido a raridade de seu diagnóstico e importância de estabelecer diagnóstico diferencial com doenças de maior prevalência.

5.
Front Immunol ; 13: 869825, 2022.
Article in English | MEDLINE | ID: covidwho-1809406

ABSTRACT

Phage display is a well-established technology for in vitro selection of monoclonal antibodies (mAb), and more than 12 antibodies isolated from phage displayed libraries of different formats have been approved for therapy. We have constructed a large size (10^11) human antibody VH domain library based on thermo-stable, aggregation-resistant scaffolds. This diversity was obtained by grafting naturally occurring CDR2s and CDR3s from healthy donors with optimized primers into the VH library. This phage-displayed library was used for bio-panning against various antigens. So far, panels of binders have been isolated against different viral and tumor targets, including the SARS-CoV-2 RBD, HIV-1 ENV protein, mesothelin and FLT3. In the present study, we discuss domain library construction, characterize novel VH binders against human CD22 and PD-L1, and define our design process for antibody domain drug conjugation (DDC) as tumoricidal reagents. Our study provides examples for the potential applications of antibody domains derived from library screens in therapeutics and provides key information for large size human antibody domain library construction.


Subject(s)
COVID-19 , Immunoglobulin Heavy Chains , Antibodies, Monoclonal , B7-H1 Antigen , Humans , Peptide Library , SARS-CoV-2 , Sialic Acid Binding Ig-like Lectin 2/metabolism
6.
Journal of Allergy and Clinical Immunology ; 149(3):874-878, 2022.
Article in English | EMBASE | ID: covidwho-1720145
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