scholarly journals Dual-reactive B cells are autoreactive and highly enriched in the plasmablast and memory B cell subsets of autoimmune mice

2012 ◽  
Vol 209 (10) ◽  
pp. 1797-1812 ◽  
Author(s):  
Emilie M. Fournier ◽  
Maria-Gabriela Velez ◽  
Katelyn Leahy ◽  
Cristina L. Swanson ◽  
Anatoly V. Rubtsov ◽  
...  

Rare dual-reactive B cells expressing two types of Ig light or heavy chains have been shown to participate in immune responses and differentiate into IgG+ cells in healthy mice. These cells are generated more often in autoreactive mice, leading us to hypothesize they might be relevant in autoimmunity. Using mice bearing Igk allotypic markers and a wild-type Ig repertoire, we demonstrate that the generation of dual-κ B cells increases with age and disease progression in autoimmune-prone MRL and MRL/lpr mice. These dual-reactive cells express markers of activation and are more frequently autoreactive than single-reactive B cells. Moreover, dual-κ B cells represent up to half of plasmablasts and memory B cells in autoimmune mice, whereas they remain infrequent in healthy mice. Differentiation of dual-κ B cells into plasmablasts is driven by MRL genes, whereas the maintenance of IgG+ cells is partly dependent on Fas inactivation. Furthermore, dual-κ B cells that differentiate into plasmablasts retain the capacity to secrete autoantibodies. Overall, our study indicates that dual-reactive B cells significantly contribute to the plasmablast and memory B cell populations of autoimmune-prone mice suggesting a role in autoimmunity.

2022 ◽  
Author(s):  
Cory A Perugino ◽  
Hang Liu ◽  
Jared Feldman ◽  
Blake M Hauser ◽  
Catherine Jacob-Dolan ◽  
...  

In previously unvaccinated and uninfected individuals, non-RBD SARS-CoV-2 spike specific B cells were prominent in two distinct, durable, resting, cross-reactive, preexisting switched memory B cell compartments. While pre-existing RBD-specific B cells were extremely rare in uninfected and unvaccinated individuals, these two preexisting switched memory B cell compartments were molded by vaccination and infection to become the primary source of RBD-specific B cells that are triggered by vaccine boosting. The frequency of wild-type RBD-binding memory B cells that cross-react with the Omicron variant RBD did not alter with boosting. In contrast, after a boost, B cells recognizing the full-length Omicron variant spike protein expanded, with pre-existing resting memory B cells differentiating almost quantitatively into effector B cell populations. B cells derived from ancient pre-existing memory cells and that recognize the full-length wild-type spike with the highest avidity after boosting are the B cells that also bind the Omicron variant spike protein.


2015 ◽  
Vol 112 (38) ◽  
pp. E5281-E5289 ◽  
Author(s):  
Bettina Budeus ◽  
Stefanie Schweigle de Reynoso ◽  
Martina Przekopowitz ◽  
Daniel Hoffmann ◽  
Marc Seifert ◽  
...  

Our knowledge about the clonal composition and intraclonal diversity of the human memory B-cell compartment and the relationship between memory B-cell subsets is still limited, although these are central issues for our understanding of adaptive immunity. We performed a deep sequencing analysis of rearranged immunoglobulin (Ig) heavy chain genes from biological replicates, covering more than 100,000 memory B lymphocytes from two healthy adults. We reveal a highly similar B-cell receptor repertoire among the four main human IgM+ and IgG+ memory B-cell subsets. Strikingly, in both donors, 45% of sequences could be assigned to expanded clones, demonstrating that the human memory B-cell compartment is characterized by many, often very large, B-cell clones. Twenty percent of the clones consisted of class switched and IgM+(IgD+) members, a feature that correlated significantly with clone size. Hence, we provide strong evidence that the vast majority of Ig mutated B cells—including IgM+IgD+CD27+ B cells—are post-germinal center (GC) memory B cells. Clone members showed high intraclonal sequence diversity and high intraclonal versatility in Ig class and IgG subclass composition, with particular patterns of memory B-cell clone generation in GC reactions. In conclusion, GC produce amazingly large, complex, and diverse memory B-cell clones, equipping the human immune system with a versatile and highly diverse compartment of IgM+(IgD+) and class-switched memory B cells.


Blood ◽  
2011 ◽  
Vol 118 (8) ◽  
pp. 2150-2158 ◽  
Author(s):  
Magdalena A. Berkowska ◽  
Gertjan J. A. Driessen ◽  
Vasilis Bikos ◽  
Christina Grosserichter-Wagener ◽  
Kostas Stamatopoulos ◽  
...  

Abstract Multiple distinct memory B-cell subsets have been identified in humans, but it remains unclear how their phenotypic diversity corresponds to the type of responses from which they originate. Especially, the contribution of germinal center-independent responses in humans remains controversial. We defined 6 memory B-cell subsets based on their antigen-experienced phenotype and differential expression of CD27 and IgH isotypes. Molecular characterization of their replication history, Ig somatic hypermutation, and class-switch profiles demonstrated their origin from 3 different pathways. CD27−IgG+ and CD27+IgM+ B cells are derived from primary germinal center reactions, and CD27+IgA+ and CD27+IgG+ B cells are from consecutive germinal center responses (pathway 1). In contrast, natural effector and CD27−IgA+ memory B cells have limited proliferation and are also present in CD40L-deficient patients, reflecting a germinal center-independent origin. Natural effector cells at least in part originate from systemic responses in the splenic marginal zone (pathway 2). CD27−IgA+ cells share low replication history and dominant Igλ and IgA2 use with gut lamina propria IgA+ B cells, suggesting their common origin from local germinal center-independent responses (pathway 3). Our findings shed light on human germinal center-dependent and -independent B-cell memory formation and provide new opportunities to study these processes in immunologic diseases.


2018 ◽  
Vol 2 ◽  
pp. 97 ◽  
Author(s):  
Luke Muir ◽  
Paul F. McKay ◽  
Velislava N. Petrova ◽  
Oleksiy V. Klymenko ◽  
Sven Kratochvil ◽  
...  

Background:Human memory B cells play a vital role in the long-term protection of the host from pathogenic re-challenge. In recent years the importance of a number of different memory B cell subsets that can be formed in response to vaccination or infection has started to become clear. To study memory B cell responses, cells can be culturedex vivo,allowing for an increase in cell number and activation of these quiescent cells, providing sufficient quantities of each memory subset to enable full investigation of functionality. However, despite numerous papers being published demonstrating bulk memory B cell culture, we could find no literature on optimised conditions for the study of memory B cell subsets, such as IgM+memory B cells.Methods:Following a literature review, we carried out a large screen of memory B cell expansion conditions to identify the combination that induced the highest levels of memory B cell expansion. We subsequently used a novel Design of Experiments approach to finely tune the optimal memory B cell expansion and differentiation conditions for human memory B cell subsets. Finally, we characterised the resultant memory B cell subpopulations by IgH sequencing and flow cytometry.Results:The application of specific optimised conditions induce multiple rounds of memory B cell proliferation equally across Ig isotypes, differentiation of memory B cells to antibody secreting cells, and importantly do not alter the Ig genotype of the stimulated cells. Conclusions:Overall, our data identify a memory B cell culture system that offers a robust platform for investigating the functionality of rare memory B cell subsets to infection and/or vaccination.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 80-80
Author(s):  
Mohamed-Rachid Boulassel ◽  
Bader Yassine-Diab ◽  
Don Healey ◽  
Charles Nicolette ◽  
Rafick-Pierre Sékaly ◽  
...  

Abstract We demonstrated the enhancement of CD8-specific responses following the administration of an immune-based therapy consisting of dendritic cells (DC) electroporated with autologous amplified HIV-1 RNA and CD40 ligand (CD40 L) RNA manufactured by the Arcelis™ process in HIV patients receiving antiretroviral therapy (ART). We conducted a sub study on circulating B cell populations to further assess changes induced by this autologous DC therapy as CD40L is a major B cell co-stimulatory factor. To this end, we assessed B cell subset changes in relation to the proliferative capacity of CD4+ and CD8+ T cells response to DC targets containing the 4 HIV-1 antigens (Gag, Vpr, Rev, Nef). The co-expression of CD19, CD38, IgD, CD10, CD23, CD27, CD5, and CD138 were analyzed by multi-parametric flow cytometry to assess circulating B cell subsets such as naïve resting B-cells (Bm1), activated naïve B cells (Bm2), GC founder cells (Bm2’), centroblasts and centrocytes (Bm3 and Bm4), early memory B cells (eBm5), memory B cells (Bm5), IgD memory cells, plasma cells, and B-1 cells. Changes in B cells subsets were analyzed before and after the four intradermal injections of this immunotherapeutic product containing 1.2 × 107 DC. Ten ART treated subjects with undetectable viral load (< 50 copies/ml), median CD4+ count of 440 cells/μl (range: 316–1102), and with a CD4+ nadir > 200 cells/μl were studied. Throughout the study, no significant changes in CD4+ cell count, CD4/CD8 ratio, and no viral blips were noticed. The percentage of total B cells, Bm1, Bm2, Bm2′, eBm5, IgD memory, plasma cells, and B-1 cell subsets did not significantly change. However, a decrease in the percentage of Bm3 and Bm4 cells was found (0.36 [0.06–0.86] versus 0.11 [0.04–0.36]; P=0.05). Conversely, an important increase in the Bm5 cell subset was evidenced (10.4 [1.6–24.2] versus 18.1 [5.1–27.5]; P=0.005) suggesting a proliferation of B memory cells induced by DC immunization. In addition, the multifunctional and polyvalent CD8+ T cell proliferative responses to the 4 HIV genes used in this immunotherapy were noticed in 8 out of 9 subjects available for analysis and characterized by an effector memory phenotype. No CD4+ T cell immune responses were detected, consistent with the endogenous HLA class I loading of the antigens. Collectively, these results indicate that this immunotherapy induces an increase in the B memory cell population in the absence of inducing any clinically apparent autoimmunity along with strong HIV specific multifunctional CD8+ T cell specific immune responses.


2017 ◽  
Vol 2 ◽  
pp. 97 ◽  
Author(s):  
Luke Muir ◽  
Paul F. McKay ◽  
Velislava N. Petrova ◽  
Oleksiy V. Klymenko ◽  
Sven Kratochvil ◽  
...  

Background:Human memory B cells play a vital role in the long-term protection of the host from pathogenic re-challenge. In recent years the importance of a number of different memory B cell subsets that can be formed in response to vaccination or infection has started to become clear. To study memory B cell responses, cells can be culturedex vivo,allowing for an increase in cell number and activation of these quiescent cells, providing sufficient quantities of each memory subset to enable full investigation of functionality. However, despite numerous papers being published demonstrating bulk memory B cell culture, we could find no literature on optimised conditions for the study of memory B cell subsets, such as IgM+memory B cells.Methods:Following a literature review, we carried out a large screen of memory B cell expansion conditions to identify the combination that induced the highest levels of memory B cell expansion. We subsequently used a novel Design of Experiments approach to finely tune the optimal memory B cell expansion and differentiation conditions for human memory B cell subsets. Finally, we characterised the resultant memory B cell subpopulations by IgH sequencing and flow cytometry.Results:The application of specific optimised conditions induce multiple rounds of memory B cell proliferation equally across Ig isotypes, differentiation of memory B cells to antibody secreting cells, and importantly do not alter the Ig genotype of the stimulated cells. Conclusions:Overall, our data identify a memory B cell culture system that offers a robust platform for investigating the functionality of rare memory B cell subsets to infection and/or vaccination.


Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 821-821 ◽  
Author(s):  
Sandrine Roulland ◽  
Jean-marc Navarro ◽  
Pierre Grenot ◽  
Michele Milili ◽  
Julie Agopian ◽  
...  

Abstract Follicular lymphoma (FL) is one of the most common B-cell lymphoma, and remains virtually incurable despite its relatively indolent nature. T(14;18)(q32;q21), the genetic hallmark and early initiating event of FL pathogenesis, is also present at low frequency (10−5–10−7) in blood from healthy individuals (HI), indicating that t(14;18) and the ensuing BCL2 overexpression is necessary but not sufficient for malignant transformation. It has long been assumed that in HI, t(14;18) is carried by circulating quiescent naïve B-cells, where its oncogenic potential would be restrained. Yet, several reports, including long-term persistence and immunomodulation of t(14;18)+ cells in lymphoma-free individuals, led us to question this model and investigate the status of circulating t(14;18)+ cells in HI. We first determined if t(14;18)+ cells are naïve B-cells by assessing class-switch recombination (CSR) on the translocated allele. Using 2 long-range PCR assays designed to amplify unswitched BCL2/Sμ and switched BCL2/Sg regions, DNA samples from 6 HI with t(14;18) were tested. Contrary to previous assumptions, our data clearly show that most peripheral t(14;18)+ cells already underwent CSR (n=5/6) and therefore that most t(14;18)+ cells are not naïve B-cells. Are they then memory B cells? Naïve and memory B cell subsets from 9 HI were isolated by cell sorting according to IgD and CD27 markers, and the rate of t(14;18) analyzed in each subset relatively to that of the total B cells. Strikingly, while the level of naïve t(14;18)+ cells remained at baseline for all individuals, memory B-cells tightly accounted for the wide modulation of t(14;18) frequencies observed between individuals. In addition, sequence analysis of t(14;18) clones revealed that this wide modulation was not due to the accumulation of clonally unrelated t(14;18) naïve B-cells, but rather to the clonal expansion of t(14;18)-bearing memory B-cells. To further define the t(14;18)+ cells, we next examined the repartition of the translocation in the IgD−/CD27+ and IgD+/CD27+ memory B-cell subsets. Unexpectedly, we found that the IgD+/CD27+ subset contained significantly higher rates of translocation than the IgD−/CD27+, both in terms of prevalence and frequency. Thus, while CSR is found in the majority of translocated alleles (~75%), most t(14;18)+ memory B cells have not switched their productive allele (~70%) and express an IgM/D. Most importantly, although atypical among physiological peripheral B-cells, this “allelic paradox” is a specific hallmark of FL, and suggests the presence of the same selective pressure in favor of sIgM expression on a B-cell population that is at the same time permanently driven to switch. In line with B-cell hyperplasia in BCL2 transgenic mice slowly progressing to low grade lymphoma, it is likely that “FL-like” cells in HI are rescued by BCL2 from apoptosis, and “frozen” at a differentiation stage in which constitutive AID expression drives continuous somatic hypermutation and CSR activity, two mechanisms conferring a high propensity for genomic instability. Altogether, our findings identify a novel intermediate step in early lymphomagenesis, and strongly impact both on the current understanding of disease progression from potent pre-malignant niches, and on the proper handling of t(14;18) frequency in blood as a potential early biomarker for lymphoma.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Fadwa A. Abdelwahab ◽  
Khaled M. Hassanein ◽  
Helal F. Hetta ◽  
Mohamed O. Abdelmalek ◽  
Asmaa M. Zahran ◽  
...  

AbstractType II diabetes (T2D) may worsen the course of hepatitis C virus infection with a greater risk of liver cirrhosis (LC) and hepatocellular carcinoma (HCC). In chronic viral infections, the deranged B cell subset signifies uncontrolled disease. The study aimed to verify the relation between B cell subsets’ distribution and liver disease progression in chronic hepatitis C (CHC) patients with T2D. A total of 67 CHC patients were divided into two groups; 33 non-diabetic and 34 with T2D. Each group was subdivided into CHC-without LC or HCC (N-CHC), CHC-with LC (CHC-LC), and CHC-with HCC (CHC-HCC). Twenty-seven healthy individuals also participated as controls. Flow cytometry was used to analyze CD19+ B cell subsets based on the expression of CD24 and CD38. CD19+CD24hiCD38hi Immature/transitional B cells elevated in diabetic than non-diabetic patients. In diabetic patients, while CD19+CD24+CD38− primarily memory B cells were higher in CHC-N and CHC-HCC groups than LC with a good predictive accuracy of LC, the opposite was observed for CD19+CD24−CD38− new memory B cells. Only in diabetic patients, the CD19+CD24intCD38int naïve mature B cells were high in CHC-HCC patients with good prognostic accuracy of HCC. Merely in diabetic patients, several correlations were observed between B cell subsets and liver function. Immature/transitional B cells increase remarkably in diabetic CHCpatients and might have a role in liver disease progression. Memory and Naïve B cells are good potential predictors of LC and HCCin diabetic CHCpatients, respectively. Further studies are needed to investigate the role of the CD19+CD24−CD38− new memory B cells in disease progression in CHC patients.


Author(s):  
Anuradha Rajamanickam ◽  
Nathella Pavan Kumar ◽  
Arul Nancy P ◽  
Nandhini Selvaraj ◽  
Saravanan Munisankar ◽  
...  

It is essential to examine the longevity of the defensive immune response engendered by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. We examined the SARS-CoV-2-specific antibody responses and ex vivo memory B-cell subsets in seven groups of individuals with COVID-19 classified based on days since reverse-transcription polymerase chain reaction confirmation of SARS-CoV-2 infection. Our data showed that the levels of IgG and neutralizing antibodies started increasing from days 15 to 30 to days 61 to 90, and plateaued thereafter. The frequencies of naive B cells and atypical memory B cells decreased from days 15 to 30 to days 61 to 90, and plateaued thereafter. In contrast, the frequencies of immature B cells, classical memory B cells, activated memory B cells, and plasma cells increased from days 15 to 30 to days 61 to 90, and plateaued thereafter. Patients with severe COVID-19 exhibited increased frequencies of naive cells, atypical memory B cells, and activated memory B cells, and lower frequencies of immature B cells, central memory B cells, and plasma cells when compared with patients with mild COVID-19. Therefore, our data suggest modifications in memory B-cell subset frequencies and persistence of humoral immunity in convalescent individuals with COVID-19.


Sign in / Sign up

Export Citation Format

Share Document