scholarly journals Correlation of Molecular Characteristics, Isotype, and In Vitro Functional Activity of Human Antipneumococcal Monoclonal Antibodies

2006 ◽  
Vol 74 (2) ◽  
pp. 1025-1031 ◽  
Author(s):  
H. E. Baxendale ◽  
D. Goldblatt
Keyword(s):  
Monoclonal Antibodies ◽  
B Cells ◽  
Structure Function ◽  
Amino Acid Replacement ◽  
Memory B Cells ◽  
Molecular Characteristics ◽  
Cell Repertoire ◽  
V Gene ◽  
Low Levels

ABSTRACT Structure-function correlations of pneumococcal antibodies are important in predicting how changes in the pneumococcus (Pnc)-specific B-cell repertoire will influence humoral immunity against invasive Pnc disease. Using a unique panel of human hybridomas derived from memory B cells after pneumococcal conjugate vaccination, we analyzed the structure-function relationship of nine monoclonal antibodies (MAbs) reactive to Pnc polysaccharides. The avidities of the antibodies correlated with the avidity of donor immune serum (R, 0.7; P < 0.025), and this relationship was particularly strong for immunoglobulin A clones (R, 1; P < 0.0005), suggesting that the MAbs may represent important clones contributing to serological memory. Common heavy-light chain combinations and amino acid replacement mutations were seen for clones with the same serospecificity from different individuals. The two highest-avidity MAbs used Vh3-48, and two MAbs with the same serospecificity, using the same V gene pairings (Vh3-7 and Vk2A17), had similar avidities, suggesting that canonical V gene use makes an important contribution to avidity. Although all clones had mutation levels consistent with their being derived from memory B cells, low levels of replacement mutation were associated with high avidities. This relationship was strongest for Vh genes (R, 0.8; P < 0.01). Opsonophagocytosis was demonstrated for all clones, and there was a trend toward clones using canonical genes with low levels of mutation having high opsonophagocytic activities (R, 0.5). These data suggest that the use of canonical genes in the Pnc antibody response is associated with highly functional antibodies and that most somatic mutations seen in these genes are not antigen selected.

scholarly journals Ex vivo characterization and isolation of rare memory B cells with antigen tetramers

Blood ◽  
2011 ◽  
Vol 118 (2) ◽  
pp. 348-357 ◽  
Author(s):  
Bettina Franz ◽  
Kenneth F. May ◽  
Glenn Dranoff ◽  
Kai Wucherpfennig
Keyword(s):  
B Cells ◽  
B Cell ◽  
Single Cell ◽  
Ex Vivo ◽  
Cell Receptor ◽  
Memory B Cells ◽  
Cell Repertoire ◽  
Low Frequencies

Abstract Studying human antigen-specific memory B cells has been challenging because of low frequencies in peripheral blood, slow proliferation, and lack of antibody secretion. Therefore, most studies have relied on conversion of memory B cells into antibody-secreting cells by in vitro culture. To facilitate direct ex vivo isolation, we generated fluorescent antigen tetramers for characterization of memory B cells by using tetanus toxoid as a model antigen. Brightly labeled memory B cells were identified even 4 years after last immunization, despite low frequencies ranging from 0.01% to 0.11% of class-switched memory B cells. A direct comparison of monomeric to tetrameric antigen labeling demonstrated that a substantial fraction of the B-cell repertoire can be missed when monomeric antigens are used. The specificity of the method was confirmed by antibody reconstruction from single-cell sorted tetramer+ B cells with single-cell RT-PCR of the B-cell receptor. All antibodies bound to tetanus antigen with high affinity, ranging from 0.23 to 2.2 nM. Furthermore, sequence analysis identified related memory B cell and plasmablast clones isolated more than a year apart. Therefore, antigen tetramers enable specific and sensitive ex vivo characterization of rare memory B cells as well as the production of fully human antibodies.

scholarly journals THU0035 OX40L EXPRESSING NEUTROPHILS INDUCE CD4 T FOLLICULAR AND PERIPHERAL HELPER CELL DIFFERENTIATION IN SYSTEMIC LUPUS ERYTHEMATOSUS

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 230.2-231
Author(s):  
A. Pappalardo ◽  
E. Wojciechowski ◽  
I. Odriozola ◽  
I. Douchet ◽  
N. Merillon ◽  
...  
Keyword(s):  
Systemic Lupus Erythematosus ◽  
T Cells ◽  
B Cells ◽  
Lupus Erythematosus ◽  
Cd4 T Cells ◽  
Close Contact ◽  
Memory B Cells ◽  
Systemic Lupus ◽  
Research Support

Background:Neutrophils have been described as potent antigen-presenting cells able to activate T cells by MHC/TCR interaction and costimulatory molecules in tumor immunity. However, little is known about the direct interaction between neutrophils and CD4 T cells with respect to systemic lupus erythematosus (SLE). We have previously shown that OX40L expressed by monocytes from SLE patients promote the differentiation of naïve and memory cells into IL21 secreting T cells that are able to help B cells1,2.Objectives:In this study, we investigate OX40L expression on neutrophils from SLE patients and contribution of these OX40L+neutrophils in SLE pathogenesis to modulation of the B cell helper role of CD4 T cells.Methods:Surface expression of co-stimulatory molecules (OX40L, ICOSL, GITRL, 4-1BBL) on neutrophils from SLE patients and healthy donors (HD) was measured by flow cytometry (FC). Neutrophils from HD were stimulated with TLR7 or TLR8 agonists and IFNα after 5 hours of culture, OX40L expression was measured by FC and Western Blotting. CD4 T cells were cultured with the stimulated neutrophils for 3 days. At the end of the co-culture, percentages of IL21-expressing T follicular (Tfh) and peripheral helper (Tph) cells measured by FC. These generated T cells were also cultured in the presence of memory B cells. After 5 days of co-culture, plasmablast generation and Ig levels were assessed by FC and ELISA, respectively. Inhibition of OX40-OX40L interaction in vitro was achieved using ISB 830, a novel anti-OX40 mAb currently used in clinical trials.Results:Among the co-stimulatory molecules tested, percentages of OX40L+neutrophils in SLE (n=54) were increased compared to HD (n=25)(mean + SD: HD = 1,34%±1.62 vs SLE = 4,53%±8.1; p=0.29). OX40L expression positively correlated with SLE disease activity score (SLEDAI) (p = 0,04; r = 0,31) and with anti-DNA antibodies (p= 0,04, r = 0,33). Of note, the percentage of OX40L+neutrophils was higher in anti-sm-RNP+patients (n=16, mean= 9%±9.8), compared to anti-sm-RNP-patients (n=27, mean = 1,4%±2.5; p = 0,02). The percentage of OX40L+neutrophils was higher in patients with class III or IV lupus nephritis, and inflammatory infiltrate within the kidney biopsy disclosed OX40L+neutrophils, in close contact with T cells. Neutrophils from HD express OX40L with TLR8 agonist, or IFNα priming followed by TLR7 agonist. When memory CD4 T cells were cultured in the presence of TLR8-stimulated neutrophils, the proportion of IL21-expressing Tfh (CXCR5+PD1+) and Tph (CXCR5-PD1hi) were increased, compared to culture with unstimulated neutrophils. This process was dependent on OX40-OX40L interactions, since in vitro treatment with the anti-OX40 blocking antibody ISB 830, inhibited the differentiation of memory T cells into Tfh and Tph. Both generated Tfh and Tph were able to promote the differentiation of memory B cells into Ig-secreting plasmablasts.Conclusion:Our results disclose an unprecedented phenomenon where cross-talk between TLR7/8-activated neutrophils and CD4 lymphocytes operates through OX40L-OX40 costimulation, and neutrophils promote the differentiation of pro-inflammatory Tfh and Tph, as well as IL21 production. Therefore, OX40L/OX40 should be considered as a potentially therapeutic axis in SLE patients.References:[1]Jacquemin et al. Immunity 2015;[2]Jacquemin et al. JCI Insight 2018Disclosure of Interests:Angela Pappalardo Grant/research support from: Ichnos Sciences, Elodie Wojciechowski: None declared, Itsaso Odriozola: None declared, Isabelle Douchet: None declared, Nathalie Merillon: None declared, Andrea Boizard-Moracchini: None declared, Pierre Duffau: None declared, Estibaliz Lazaro: None declared, Marie-Agnes Doucey Employee of: Ichnos Sciences, Lamine Mbow Employee of: Ichnos Sciences, Christophe Richez Consultant of: Abbvie, Amgen, Mylan, Pfizer, Sandoz and UCB., Patrick Blanco Grant/research support from: Ichnos Sciences

scholarly journals Monoclonal antibodies to the 140,000 mol wt glycoprotein of B lymphocyte membranes (CR2 receptor) initiates proliferation of B cells in vitro

Blood ◽  
1985 ◽  
Vol 66 (4) ◽  
pp. 824-829
Author(s):  
BS Wilson ◽  
JL Platt ◽  
NE Kay
Keyword(s):  
Monoclonal Antibodies ◽  
B Cells ◽  
B Cell ◽  
Peripheral Blood ◽  
B Lymphocyte ◽  
Human Peripheral Blood ◽  
Raji Cell ◽  
Lymphoid Cells ◽  
Humoral Immune

Several mouse monoclonal IgG antibodies (AB1, AB2, AB3, and AB5) were developed that reacted with a 140,000 mol wt glycoprotein on the surface of cultured RAJI B lymphoid cells. The antibodies reacted with purified normal human peripheral blood B cells and CLL Ig+ B cells and showed specific germinal center and mantle zone staining in tissue sections of secondary lymphoid organs. Immunodepletion studies using 125I surface-labeled Raji cell membrane antigens demonstrated that the antigen identified by AB5 is the same 140,000 mol wt glycoprotein detected by anti-B2 that has recently been shown to react with the C3d fragment or CR2 receptor. (Iida et al: J Exp Med 158:1021, 1983). Addition of the AB series and anti-B2 monoclonal antibodies to cultures of purified human peripheral blood B cells resulted in the uptake of 3H- thymidine at two to six times background control levels provided that irradiated autologous T cells were added to the culture. Stimulation was not evoked by other monoclonal antibodies to B cell surface molecules (ie, B1, BA-1, BA-2, and HLA-DR). Pepsin-generated F(ab')2 fragments of anti-CR2 antibodies were essentially as effective as the intact IgG molecule in stimulating B cells. Induction of B cell proliferation by antibody binding to CR2 suggests that the C3d receptor may have an integral role in regulation of humoral immune response.

scholarly journals Epstein-Barr Virus LMP2A Alters In Vivo and In Vitro Models of B-Cell Anergy, but Not Deletion, in Response to Autoantigen

2005 ◽  
Vol 79 (12) ◽  
pp. 7355-7362 ◽  
Author(s):  
Michelle A. Swanson-Mungerson ◽  
Robert G. Caldwell ◽  
Rebecca Bultema ◽  
Richard Longnecker
Keyword(s):  
B Cells ◽  
B Cell ◽  
Epstein Barr Virus ◽  
Nuclear Translocation ◽  
Cell Receptor ◽  
Barr Virus ◽  
Low Levels ◽  
Epstein Barr

ABSTRACT A significant percentage of the population latently harbors Epstein-Barr virus (EBV) in B cells. One EBV-encoded protein, latent membrane protein 2A (LMP2A), is expressed in tissue culture models of EBV latent infection, in human infections, and in many of the EBV-associated proliferative disorders. LMP2A constitutively activates proteins involved in the B-cell receptor (BCR) signal transduction cascade and inhibits the antigen-induced activation of these proteins. In the present study, we investigated whether LMP2A alters B-cell receptor signaling in primary B cells in vivo and in vitro. LMP2A does not inhibit antigen-induced tolerance in response to strong stimuli in an in vivo tolerance model in which B cells are reactive to self-antigen. In contrast, LMP2A bypasses anergy induction in response to low levels of soluble hen egg lysozyme (HEL) both in vivo and in vitro as determined by the ability of LMP2A-expressing HEL-specific B cells to proliferate and induce NF-κB nuclear translocation after exposure to low levels of antigen. Furthermore, LMP2A induces NF-κB nuclear translocation independent of BCR cross-linking. Since NF-κB is required to bypass tolerance induction, this LMP2A-dependent NF-κB activation may complete the tolerogenic signal induced by low levels of soluble HEL. Overall, the findings suggest that LMP2A may not inhibit BCR-induced signals under all conditions as previously suggested by studies with EBV immortalized B cells.

scholarly journals In VitroMeasles Virus Infection of Human Lymphocyte Subsets Demonstrates High Susceptibility and Permissiveness of both Naive and Memory B Cells

2018 ◽  
Vol 92 (8) ◽  
pp. e00131-18 ◽  
Author(s):  
Brigitta M. Laksono ◽  
Christina Grosserichter-Wagener ◽  
Rory D. de Vries ◽  
Simone A. G. Langeveld ◽  
Maarten D. Brem ◽  
...  
Keyword(s):  
T Cells ◽  
B Cells ◽  
B Cell ◽  
Immune Suppression ◽  
Peripheral Blood ◽  
Measles Virus ◽  
Memory B Cells ◽  
T And B Cells ◽  
B Cell Subsets

ABSTRACTMeasles is characterized by a transient immune suppression, leading to an increased risk of opportunistic infections. Measles virus (MV) infection of immune cells is mediated by the cellular receptor CD150, expressed by subsets of lymphocytes, dendritic cells, macrophages, and thymocytes. Previous studies showed that human and nonhuman primate memory T cells express higher levels of CD150 than naive cells and are more susceptible to MV infection. However, limited information is available about the CD150 expression and relative susceptibility to MV infection of B-cell subsets. In this study, we assessed the susceptibility and permissiveness of naive and memory T- and B-cell subsets from human peripheral blood or tonsils toin vitroMV infection. Our study demonstrates that naive and memory B cells express CD150, but at lower frequencies than memory T cells. Nevertheless, both naive and memory B cells proved to be highly permissive to MV infection. Furthermore, we assessed the susceptibility and permissiveness of various functionally distinct T and B cells, such as helper T (TH) cell subsets and IgG- and IgA-positive memory B cells, in peripheral blood and tonsils. We demonstrated that TH1TH17 cells and plasma and germinal center B cells were the subsets most susceptible and permissive to MV infection. Our study suggests that both naive and memory B cells, along with several other antigen-experienced lymphocytes, are important target cells of MV infection. Depletion of these cells potentially contributes to the pathogenesis of measles immune suppression.IMPORTANCEMeasles is associated with immune suppression and is often complicated by bacterial pneumonia, otitis media, or gastroenteritis. Measles virus infects antigen-presenting cells and T and B cells, and depletion of these cells may contribute to lymphopenia and immune suppression. Measles has been associated with follicular exhaustion in lymphoid tissues in humans and nonhuman primates, emphasizing the importance of MV infection of B cellsin vivo. However, information on the relative susceptibility of B-cell subsets is scarce. Here, we compared the susceptibility and permissiveness toin vitroMV infection of human naive and memory T- and B-cell subsets isolated from peripheral blood or tonsils. Our results demonstrate that both naive and memory B cells are more permissive to MV infection than T cells. The highest infection levels were detected in plasma cells and germinal center B cells, suggesting that infection and depletion of these populations contribute to reduced host resistance.

scholarly journals The V Gene Repertoires of Classical and Atypical Memory B Cells in Malaria-Susceptible West African Children

2015 ◽  
Vol 194 (3) ◽  
pp. 929-939 ◽  
Author(s):  
Severin Zinöcker ◽  
Christine E. Schindler ◽  
Jeff Skinner ◽  
Tobias Rogosch ◽  
Michael Waisberg ◽  
...  
Keyword(s):  
B Cells ◽  
West African ◽  
Memory B Cells ◽  
African Children ◽  
V Gene

Mechanisms of hypergammaglobulinemia and impaired antigen-specific humoral immunity in HIV-1 infection

Blood ◽  
2004 ◽  
Vol 103 (6) ◽  
pp. 2180-2186 ◽  
Author(s):  
Angelo De Milito ◽  
Anna Nilsson ◽  
Kehmia Titanji ◽  
Rigmor Thorstensson ◽  
Elisabet Reizenstein ◽  
...  
Keyword(s):  
B Cells ◽  
B Lymphocytes ◽  
Humoral Immunity ◽  
Viral Infections ◽  
Ex Vivo ◽  
Memory B Cells ◽  
Differentiation Markers ◽  
Specific Antigens ◽  
Hiv 1

Abstract Hypergammaglobulinemia and defective humoral immunity are hallmarks of HIV-1 infection. Naive B cells have been recently suggested as the major source of hypergammaglobulinemia in chronic viral infections. We recently reported that HIV-1–infected patients carry low levels of memory B cells. Here we studied whether defects in the naive and memory B cells in HIV-1–infected patients translated into hypergammaglobulinemia and defective humoral immunity against specific antigens. Naive B cells from HIV-1–infected patients exhibited abnormal expression of the activation/differentiation markers CD70 and leukocyte-associated Ig-like receptor (LAIR-1). Activated naive B cells from patients showed a significant increase in the intracellular immunoglobulin G (IgG) content ex vivo and this activated phenotype correlated to hypergammaglobulinemia and to the ability of naive B cells from patients to secrete IgG in vitro. We analyzed the levels of antibodies to tetanus toxoid, measles, and HIV-1 in relation to memory B cells and observed a significant reduction of antigen-specific antibodies in patients with low-memory B lymphocytes. Nevertheless, hypergammaglobulinemia and levels of polyspecific self-reactive antibodies were comparable in patients with normal and low memory B cells. We conclude that reduction of memory B lymphocytes in HIV-1 infection correlates with defective humoral immunity and that hyperactivated naive B cells may represent the source of abnormal IgG production in HIV-1 infection. Our results may be relevant to the design of HIV-1 therapeutical vaccines and to the clinical management of HIV-1–infected patients.

In vitro IgE inhibition in B cells by anti-CD23 monoclonal antibodies is functionally dependent on the immunoglobulin Fc domain

2000 ◽  
Vol 22 (2) ◽  
pp. 131-141 ◽  
Author(s):  
Takehiko Nakamura ◽  
William S Kloetzer ◽  
Peter Brams ◽  
Kandasamy Hariharan ◽  
Soulaima Chamat ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
B Cells
Sign in / Sign up

Export Citation Format

Share Document