Case Report: Persistent Hypogammaglobulinemia More Than 10 Years After Rituximab Given Post-HSCT

Rituximab (RTX) is an anti-CD20 monoclonal antibody that targets B cells—from the immature pre-B-cell stage in the bone marrow to mature circulating B cells—while preserving stem cells and plasma cells. It is used to treat autoimmune diseases, hematological malignancies, or complications after hematopoietic stem cell transplantation (HSCT). Its safety profile is acceptable; however, a subset of patients can develop persistent hypogammaglobulinemia and associated severe complications, especially in pediatric populations. We report the unrelated cases of two young men aged 17 and 22, presenting with persistent hypogammaglobulinemia more than 7 and 10 years after treatment with RTX, respectively, and administered after HSCT for hemolytic anemia and Epstein–Barr virus reactivation, respectively. Both patients’ immunological workups showed low levels of total immunoglobulin, vaccine antibodies, and class switched-memory B cells but an increase in naive B cells, which can also be observed in primary immunodeficiencies such as those making up common variable immunodeficiency. Whole exome sequencing for one of the patients failed to detect a pathogenic variant causing a Mendelian immunological disorder. Annual assessments involving interruption of immunoglobulin replacement therapy each summer failed to demonstrate the recovery of endogenous immunoglobulin production or normal numbers of class switched-memory B cells 7 and 10 years after the patients’ respective treatments with RTX. Although the factors that may lead to prolonged hypogammaglobulinemia after rituximab treatment (if necessary) remain unclear, a comprehensive immunological workup before treatment and long-term follow-up are mandatory to assess long-term complications, especially in children.

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The Normal Counterpart of IgD Myeloma Cells in Germinal Center Displays Extensively Mutated IgVH Gene, Cμ–Cδ Switch, and λ Light Chain Expression

Journal of Experimental Medicine ◽

10.1084/jem.187.8.1169 ◽

1998 ◽

Vol 187 (8) ◽

pp. 1169-1178 ◽

Cited By ~ 97

Author(s):

Christophe Arpin ◽

Odette de Bouteiller ◽

Diane Razanajaona ◽

Isabelle Fugier-Vivier ◽

Francine Brière ◽

...

Keyword(s):

Bone Marrow ◽

B Cells ◽

Light Chain ◽

Germinal Center ◽

Plasma Cells ◽

Precursor Cells ◽

Memory B Cells ◽

Hematopoietic Stem ◽

Myeloma Cells ◽

Λ Light Chain

Human myeloma are incurable hematologic cancers of immunoglobulin-secreting plasma cells in bone marrow. Although malignant plasma cells can be almost eradicated from the patient's bone marrow by chemotherapy, drug-resistant myeloma precursor cells persist in an apparently cryptic compartment. Controversy exists as to whether myeloma precursor cells are hematopoietic stem cells, pre–B cells, germinal center (GC) B cells, circulating memory cells, or plasma blasts. This situation reflects what has been a general problem in cancer research for years: how to compare a tumor with its normal counterpart. Although several studies have demonstrated somatically mutated immunoglobulin variable region genes in multiple myeloma, it is unclear if myeloma cells are derived from GCs or post-GC memory B cells. Immunoglobulin (Ig)D-secreting myeloma have two unique immunoglobulin features, including a biased λ light chain expression and a Cμ–Cδ isotype switch. Using surface markers, we have previously isolated a population of surface IgM−IgD+CD38+ GC B cells that carry the most impressive somatic mutation in their IgV genes. Here we show that this population of GC B cells displays the two molecular features of IgD-secreting myeloma cells: a biased λ light chain expression and a Cμ–Cδ isotype switch. The demonstration of these peculiar GC B cells to differentiate into IgD-secreting plasma cells but not memory B cells both in vivo and in vitro suggests that IgD-secreting plasma and myeloma cells are derived from GCs.

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Memory T and memory B cells share a transcriptional program of self-renewal with long-term hematopoietic stem cells

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.0511137103 ◽

2006 ◽

Vol 103 (9) ◽

pp. 3304-3309 ◽

Cited By ~ 166

Author(s):

C. J. Luckey ◽

D. Bhattacharya ◽

A. W. Goldrath ◽

I. L. Weissman ◽

C. Benoist ◽

...

Keyword(s):

Stem Cells ◽

B Cells ◽

Hematopoietic Stem Cells ◽

Memory B Cells ◽

Transcriptional Program ◽

Self Renewal ◽

Hematopoietic Stem

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Comparable Long-Term Persistence of Anti-FVIII Antibodies in Hemophilic E17 Mice on Different Genetic Backgrounds Despite Significant Differences in the Amplitude of the Immune Responses.

Blood ◽

10.1182/blood.v108.11.1027.1027 ◽

2006 ◽

Vol 108 (11) ◽

pp. 1027-1027

Author(s):

Natalie Bauer ◽

Christina Hausl ◽

Rafi U. Ahmad ◽

Bernhard Baumgartner ◽

Hans Peter Schwarz ◽

...

Keyword(s):

Immune Response ◽

B Cells ◽

Genetic Background ◽

Neutralizing Antibodies ◽

Plasma Cells ◽

Memory B Cells ◽

Mouse Strains ◽

Igg Antibodies ◽

Specific Memory

Abstract About 30% of patients with severe hemophilia A develop neutralizing antibodies against FVIII (FVIII inhibitors) following replacement therapy. The type of FVIII gene mutation as well as other predisposing genetic factors contribute to the inhibitor phenotype. Based on these findings, we asked if the genetic background modulates the long-term persistence of anti-FVIII antibodies and anti-FVIII antibody secreting plasma cells in the E17 murine hemophilia model. Furthermore, we asked if the recently described inhibition of memory-B-cell re-stimulation by high doses of FVIII is influenced by the genetic background of the murine model. E17 mice on two different genetic backgrounds (C57Bl/6J and Balb/c) were treated with four doses of 200 ng human FVIII at weekly intervals. Anti-FVIII antibodies and anti-FVIII antibody secreting plasma cells were followed up to 12 months after the last dose of FVIII. Antibody titers and subclasses of antibodies (IgM, IgG1, IgG2a, IgG2b, IgG3) were measured by ELISA. Antibody secreting plasma cells in spleen and bone marrow were detected by ELISPOT as described (Hausl et al., Thromb Haemost 2002). The re-stimulation of FVIII-specific memory B cells was studied as described recently (Hausl et al., Blood 2005). Anti-FVIII antibodies and anti-FVIII antibody secreting plasma cells were first detectable in E17 Balb/c mice. IgM antibodies in the circulation and IgM secreting plasma cells in the spleen were observed after the first dose of FVIII, IgG antibodies and IgG secreting plasma cells after the second dose. No anti-FVIII antibodies after the first dose of FVIII were observed in E17 C57BL/6J mice but both IgM and IgG antibodies as well as IgM and IgG producing plasma cells were detectable after the second dose of FVIII. The antibody response involved all IgG subclasses in both mouse strains. However, IgG1 was dominant in E17 Balb/c mice whereas IgG2a was dominant in E17 C57BL/6J mice. When the in vitro restimulation of FVIII-specific memory B cells was examined, similar patterns were observed for both mouse strains. Low concentrations of FVIII between 10 and 100 ng/ml FVIII restimulated memory B cells and induced their differentiation into antibody secreting plasma cells whereas high concentrations of FVIII between 1,000 and 20,000 ng/ml FVIII inhibited memory-B-cell-restimulation. These results indicate that the dose-dependent effect of FVIII on the restimulation of FVIII-specific memory B cells does not depend on the genetic background. The major difference between both hemophilic mouse strains was the amplitude of the anti-FVIII immune response. Peak titers of anti-FVIII antibodies and peak concentrations of anti-FVIII antibody secreting plasma cells in spleen and bone marrow were significantly higher in E17 C57BL/6J mice than in E17 Balb/c mice. Whether or not higher ELISA titers correlate with higher Bethesda titers of neutralizing antibodies is currently being investigated. Despite the substantial differences in the amplitude of the immune response, anti-FVIII antibodies and anti-FVIII antibody secreting plasma cells persisted for the whole observation period of 12 months after the last dose of FVIII in both mouse strains. We conclude that the amplitude of the anti-FVIII immune response in hemophilic mice is significantly different between E17 C57BL/6J and E17 Balb/c mice. However, the persistence of the immune response is comparable.

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The BioNTech / Pfizer vaccine BNT162b2 induces class-switched SARS-CoV-2-specific plasma cells and potential memory B cells as well as IgG and IgA serum and IgG saliva antibodies upon the first immunization

10.1101/2021.03.10.21252001 ◽

2021 ◽

Author(s):

Anne S. Lixenfeld ◽

Inga Künsting ◽

Emily L. Martin ◽

Vera von Kopylow ◽

Selina Lehrian ◽

...

Keyword(s):

B Cells ◽

Respiratory Tract ◽

Development Process ◽

Plasma Cells ◽

Memory B Cells ◽

The Body ◽

Cd4 T Cell ◽

First Line ◽

Underlying Mechanisms

AbstractTo treat the SARS-CoV-2 virus, that enters the body through the respiratory tract, different vaccines in particular against the SARS-CoV-2 spike (S)-protein have been developed or are in the development process. For the BioNTech / Pfizer mRNA vaccine BNT162b2, which is injected twice, protection against COVID-19 has been described for the first weeks after the second vaccination. The underlying mechanisms of defense and the long-term effectiveness of this vaccine against COVID-19 are currently under investigation.In addition to the induction of systemic antibodies (Abs), Ab responses in the respiratory tract would help to form a first line of defense against SARS-CoV-2. Furthermore, protection depends on Fab-part-dependent neutralizing capacities, however, Fc-part-mediated effector mechanisms might also be important. Long-term defense would be based on the induction of long-lived antibody-producing plasma cells (PCs) and memory B cells.Here, we established different assays to analyze anti-SARS-CoV-2-S IgG and IgA Abs in blood serum and saliva as well as SARS-CoV-2-S1-reactive IgG and IgA PCs and potential memory B cells in the blood of individuals upon their first immunization with BNT162b2.We show that the vaccine induces in particular anti-SARS-CoV-2-S IgG1 and IgG3 as well as IgA1 and in some individuals also IgG2 and IgA2 serum Abs. In the saliva, we found no anti-SARS-CoV-2-S IgA, but instead IgG Abs. Furthermore, we found SARS-CoV-2-S reactive IgG+ blood PCs and potential memory B cells as well as SARS-CoV-2-S reactive IgA+ PCs and/or potential memory B cells in some individuals.Our data suggest that the vaccine induces a promising CD4+ T cell-dependent systemic IgG1 and IgG3 Ab response with IgG+ PCs and potential memory B cells. In addition to the systemic IgG response, the systemic IgA and saliva IgG response might help to improve a first line of defense in the respiratory tract against SARS-CoV-2 and its mutants.

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Targeting Long-Lived Plasma Cells Is Essential For Treating Hemophilia A Inhibitors

Blood ◽

10.1182/blood.v122.21.927.927 ◽

2013 ◽

Vol 122 (21) ◽

pp. 927-927

Author(s):

Chao Lien Liu ◽

Meghan Lyle ◽

Simon Shin ◽

Carol H. Miao

Keyword(s):

Bone Marrow ◽

B Cells ◽

Immune Responses ◽

B Cell ◽

Plasma Cells ◽

Hemophilia A ◽

Combined Treatment ◽

Therapeutic Effects ◽

Anti Cd20

Abstract The most critical and challenging problem for therapeutic treatment in hemophilia A patients is due to the formation of Inhibitory antibodies. It is hypothesized that long-lived plasma cells (LLPCs) play an important role in the persistent production of anti-FVIII antibodies in hemophilia A (HemA) inhibitor patients. The migration of plasma cells to the BM, where they become the LLPCs, is largely controlled by an interaction between the C-X-C type chemokine ligand 12 (CXCL12) produced by bone marrow (BM) stromal cells and its receptor CXC receptor4 (CXCR4; CD184) on plasma cells surface. Our previous data showed that administration of anti-murine CD20 (IgG2a) alone can deplete B cells significantly and reduce anti-FVIII inhibitor titers transiently in FVIII plasmid-treated HemA mice with pre-existing inhibitors, however, complete tolerance to FVIII was not achieved probably due to the persistence of LLPCs. We sought novel therapeutic strategies that target CXCL12/CXCR4 pathway to reduce/eliminate LLPCs and achieve the goal for long-term tolerance to FVIII in the HemA inhibitor mice. AMD3100, the CXCR4 antagonist, plus G-CSF inhibit the interaction of CXCL12 and CXCR4, thus facilitating the mobilization of stem cells and blocking the homing and retention of LLPCs. The combined treatment strategy used anti-CD20, G-CSF and AMD3100 to target B cells plus with the specific IL-2/IL-2mAb (JES6-1) complexes to target T cells for preventing both T and B cell-dependent anti-FVIII immune responses. Two groups of FVIII-primed inhibitor mice were treated with different combined immunomodulation regimens: (1) IL-2 complexes+AMD3100+G-CSF+anti-CD20, (2) AMD3100+G-CSF+anti-CD20. Control mouse groups were treated with each of the single regimens and FVIII only, or untreated as the naive control. All the treatments were administered one cycle per two weeks for 6 weeks and the therapeutic effects (FVIII activities) as well as immune responses (anti-FVIII inhibitors) were evaluated at different time points after treatment. Significant expansion of Treg cells reaching a 5∼7-fold increase on the peak days (day 3-7 after treatment) was observed in the IL-2/IL-2mAb complexes treated groups, whereas ∼95% of B cell populations were depleted in the anti-CD20 treated groups. In addition, administration of AMD3100 plus G-CSF significantly reduced circulating and bone marrow CXCR4+ plasma cells by flow cytometry analysis as well as decreased FVIII-specific plasma cells in bone marrow by ELISPOT assay. Except for the control groups, the two mouse groups treated with combined immunosuppressive regimens showed a significant reduction of inhibitory titers following the treatment. Long-term responses are being followed and second challenge with FVIII plasmid will be used to evaluate the induction of long term tolerance to FVIII. These combination regimens are highly promising in modulating/eliminating pre-existing anti-FVIII antibodies and inducing long-term tolerance in FVIII primed subjects. Disclosures: No relevant conflicts of interest to declare.

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ZBTB38 is dispensable for hematopoiesis and antibody responses

10.1101/2020.06.11.145839 ◽

2020 ◽

Author(s):

Rachel Wong ◽

Deepta Bhattacharya

Keyword(s):

B Cells ◽

B Cell ◽

Germinal Center ◽

Plasma Cells ◽

Antibody Responses ◽

Conditional Knockout ◽

B Cell Differentiation ◽

Normal Numbers ◽

Hematopoietic Stem ◽

Germinal Center B Cells

AbstractMembers of the broad complex, tram track, bric-a-brac and zinc finger (BTB-ZF) family of transcription factors, such as BCL-6, ZBTB20, and ZBTB32, regulate antigen-specific B cell differentiation, plasma cell longevity, and the duration of antibody production. We found that ZBTB38, a different member of the BTB-ZF family that binds methylated DNA at CpG motifs, is highly expressed by germinal center B cells and plasma cells. To define the functional role of ZBTB38 in B cell responses, we generated mice conditionally deficient in this transcription factor. Germinal center B cells lacking ZBTB38 dysregulated very few genes relative to wild-type and heterozygous littermate controls. Accordingly, mice with hematopoietic-specific deletion of Zbtb38 showed normal germinal center B cell numbers and antibody responses following immunization with hapten-protein conjugates. Memory B cells from these animals functioned normally in secondary recall responses. Despite expression of ZBTB38 in hematopoietic stem cells, progenitors and mature myeloid and lymphoid lineages were also present in normal numbers in mutant mice. These data demonstrate that ZBTB38 is dispensable for hematopoiesis and antibody responses. These conditional knockout mice may instead be useful in defining the functional importance of ZBTB38 in other cell types and contexts.

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Epstein–Barr Virus Reactivation-Induced Immunoglobulin Production: Significance on Autoimmunity

Microorganisms ◽

10.3390/microorganisms8121875 ◽

2020 ◽

Vol 8 (12) ◽

pp. 1875

Author(s):

Keiko Nagata ◽

Kazuhiko Hayashi

Keyword(s):

B Cells ◽

Autoimmune Diseases ◽

Production System ◽

Epstein Barr Virus ◽

Plasma Cells ◽

Virus Reactivation ◽

Autoreactive B Cells ◽

Barr Virus ◽

Ebv Reactivation ◽

Epstein Barr

Epstein–Barr virus (EBV) mainly persists in B cells, which differentiate into antibody-producing cells, and thus, EBV has been implicated in autoimmune diseases. We aimed to describe the EBV reactivation and its relevance to autoimmune disease, focusing on Graves’ disease, which is an autoimmune hyperthyroidism caused by thyrotropin receptor antibodies. Circulating autoreactive B cells that have evaded from the selection have difficulties differentiating to produce antibodies. However, once EBV infects such B cells and reactivates, the B cells may become plasma cells and produce autoantibody. We herein proposed an EBV reactivation-induced Ig production system, which is a distinct pathway from the antibody production system through germinal centers and bone marrow and has the following characteristics: 1. IgM dominance, 2. ubiquitous Ig production, and 3. the rescue of autoreactive B cells, which skews Ig production toward autoantigens. IgM autoantibodies induced by EBV reactivation may activate the classical complement pathway and injure healthy tissue, which supply autoantigens for the production of affinity-matured IgG autoantibodies. Antibodies induced by EBV reactivation may play important roles in the development and exacerbation of autoimmune diseases.

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