scholarly journals SARS-CoV-2 specific B cell memory drives improved class switching and tissue homing responses to single dose Ad26.COV2.S vaccination in previously infected recipients

Author(s):  
Rob Krause ◽  
Thandeka Moyo-Gwete ◽  
Simone Richardson ◽  
Zanele Makhado ◽  
Nelia Manamela ◽  
...  

Abstract Neutralizing antibodies strongly correlate with protection for COVID-19 vaccines, but the corresponding memory B cells that form to protect against future infection are relatively understudied. Here we examine the effect of prior SARS-CoV-2 infection on the magnitude and phenotype of the B cell response to single dose Johnson and Johnson (Ad26.COV2.S) vaccination in South African health care workers. SARS-CoV-2 specific memory responses expand in response to Ad26.COV2.S and are maintained for the study duration (84 days) in all individuals. However, prior infection is associated with a greater frequency of these cells, a more prominent germinal center (GC) response, and increased class switched memory (CSM). These B cell features correlated with both neutralization and antibody-dependent cytotoxicity (ADCC) activity, and with the frequency of SARS-CoV-2 specific circulating T follicular helper cells (cTfh). In addition, the SARS-CoV-2 specific CD8+ T cell response correlated with increased memory B cell lung-homing, which was sustained in the infected group. Finally, although vaccination achieved equivalent B cell activation regardless of infection history, it was negatively impacted by age. These data show that phenotyping the B cell response to vaccination can provide mechanistic insight into the impact of prior infection on GC homing, CSM, cTfh, and neutralization activity. These data can provide early signals and mechanistic understanding to inform studies of vaccine boosting, durability, and co-morbidities.

1983 ◽  
Vol 158 (6) ◽  
pp. 2171-2176 ◽  
Author(s):  
L M Hutt-Fletcher ◽  
N Balachandran ◽  
M H Elkins

Human cytomegalovirus is shown to be a nonspecific polyclonal B cell activator. The B cell response is independent of virus replication and requires little, if any, T cell help.


2021 ◽  
Author(s):  
Samuel Bitoun ◽  
Julien Henry ◽  
Delphine Desjardins ◽  
Christelle Vauloup‐Fellous ◽  
Nicolas Dib ◽  
...  

Author(s):  
Renata Varnaitė ◽  
Marina García ◽  
Hedvig Glans ◽  
Kimia T. Maleki ◽  
John Tyler Sandberg ◽  
...  

AbstractCoronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 and has since become a global pandemic. Pathogen-specific antibodies are typically a major predictor of protective immunity, yet B cell and antibody responses during COVID-19 are not fully understood. Here, we analyzed antibody-secreting cell (ASC) and antibody responses in twenty hospitalized COVID-19 patients. The patients exhibited typical symptoms of COVID-19, and presented with reduced lymphocyte numbers and increased T cell and B cell activation. Importantly, we detected an expansion of SARS-CoV-2 nucleocapsid protein-specific ASCs in all twenty COVID-19 patients using a multicolor FluoroSpot assay. Out of the 20 patients, 16 had developed SARS-CoV-2-neutralizing antibodies by the time of inclusion in the study. SARS-CoV-2-specific IgA, IgG and IgM antibody levels positively correlated with SARS-CoV-2-neutralizing antibody titers, suggesting that SARS-CoV-2-specific antibody levels may reflect the titers of neutralizing antibodies in COVID-19 patients during the acute phase of infection. Lastly, we showed that interleukin 6 (IL-6) and C-reactive protein (CRP) concentrations were higher in serum of patients who were hospitalized for longer, supporting the recent observations that IL-6 and CRP could be used to predict COVID-19 severity. Altogether, this study constitutes a detailed description of clinical and immunological parameters in twenty COVID-19 patients, with a focus on B cell and antibody responses, and provides tools to study immune responses to SARS-CoV-2 infection and vaccination.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2235-2235
Author(s):  
W. Nicholas Haining ◽  
J. Evans ◽  
N. Seth ◽  
G. Callaway ◽  
K. Wucherpfennig ◽  
...  

Abstract Vaccination is widely used to improve pathogen-specific immunity in patients post HSCT, but it is not known whether patients can mount an effective T cell response to vaccine antigens (vAg). Moreover the relationship between T and B cell response to vAg has not been studied. We hypothesized that a sufficiently sensitive assay of T cell response to vAg would allow vaccination to be used as a tool to measure immune recovery post HSCT and improve vaccine design. We therefore: (1) developed a flow-cytometry-based approach to quantify and characterize T cells specific for vAg; (2) validated it by measuring T cell immunity to influenza A in normal donors; and (3) characterized the T and B cell response to influenza vaccination in pediatric HSCT patients. PBMC were labeled with CFSE and stimulated in vitro with whole influenza Ag. Ag-specific T cells were sensitively detected by their proliferation (loss of CFSE fluorescence) and simultaneous expression of the activation marker HLA-DR. Proliferating/active T cells could be readily detected after stimulation with influenza A Ag in healthy adult (n=4) and pediatric (n=19) donors but were absent in control conditions. Both CD4+ and CD8+ T cell proliferation was detected in all donors but one, and in children as young as 6mo. Staining with MHC I- and MHC II-tetramers confirmed that the proliferating/active population contained T cells specific for immunodominant CD8+ and CD4+ epitopes, demonstrating that vAg were processed and presented to epitope-specific T cells. To characterize the phenotype of influenza-specific T cell memory, we separated memory and naive CD4+ cells prior to antigen-stimulation. Antigen-experienced (CD45RA−/CCR7−) but not naive (CD45RA+/CCR7+) T cells proliferated to vAg confirming that the assay detected pre-existing influenza-A-specific T cell memory. We next assessed Influenza-A-specific T cell immunity before and after influenza vaccination in five pediatric HSCT recipients (mean age 10.6y, range 5–15y; mean time from transplant 13m, range 3–21m). Prior to vaccination the CD4 proliferation to influenza-A was a mean of 3.3% (range 0.04–11%). Following vaccination CD4 proliferation increased significantly in all patients (mean 19.0%, range 6.9%–31.8%, p=0.02). This increase was specific as proliferation to control Ag was unchanged. Influenza-A CD8+ proliferation also increased in 3 of 5 patients but was not statistically significant for the group consistent with the limited efficacy of soluble vAg in inducing CD8+ T cell response. All patients had detectable influenza-A-specific IgG levels prior to vaccination but despite a T cell response to vaccination in all patients, none had a significant increase in IgG level following vaccination. Only one patient had an IgM response; this patient also had the highest influenza-A-specific CD4 proliferation before and after immunization suggesting that there may be a threshold of T cell response required for a B cell response. Using a novel assay we demonstrate that a T cell response to vaccination can occur without an accompanying B cell response. This assay provides a more sensitive measure of immunity to vaccination and allows vaccine response to be used as a benchmark of strategies to accelerate post-HSCT T cell reconstitution.


2000 ◽  
Vol 192 (1) ◽  
pp. 23-30 ◽  
Author(s):  
Hirotaka Ogata ◽  
I-hsin Su ◽  
Kensuke Miyake ◽  
Yoshinori Nagai ◽  
Sachiko Akashi ◽  
...  

The susceptibility to infections induced by Gram-negative bacteria is largely determined by innate immune responses to bacteria cell wall lipopolysaccharide (LPS). The stimulation of B cells by LPS enhances their antigen-presenting capacity and is accompanied by B cell proliferation and secretion of large quantities of LPS-neutralizing antibodies. Similar to macrophages and neutrophils, the LPS-induced activation of B cells is dependent on Toll-like receptor (TLR)4. Here, we demonstrate that the responses of B cells to LPS are also regulated by another TLR protein, RP105, which is predominantly expressed on mature B cells in mice and humans. The analysis of mice homozygous for the null mutation in the RP105 gene revealed impaired proliferative and humoral immune responses of RP105-deficient B cells to LPS. Using originally LPS-unresponsive Ba/F3 cells expressing exogenous TLR4 and RP105, we demonstrate the functional cooperation between TLR4 and RP105 in LPS-induced nuclear factor κB activation. These data suggest the existence of the TLR4–RP105 signaling module in the LPS-induced B cell activation.


Blood ◽  
2004 ◽  
Vol 104 (3) ◽  
pp. 752-759 ◽  
Author(s):  
Qiang Lou ◽  
Raymond J. Kelleher ◽  
Alessandro Sette ◽  
Jenni Loyall ◽  
Scott Southwood ◽  
...  

AbstractPrevious studies have suggested that murine T cells are tolerant to epitopes derived from germ line variable regions of immunoglobulin (Ig) heavy (VH) or light chains. This has lead to the prediction that germ line VH-region epitopes found in neoplastic B cells cannot be used to provoke an antitumor immune response. To test these assumptions and address the question of how such a vaccine may alter the normal B-cell response, an antibody-forming B-cell hybridoma (1H6) expressing a conserved germ line VH gene with specificity for dextran was generated and used as a tumor model. Using algorithms for predicting major histocompatibility complex (MHC) binding, potential MHC class I and II binding peptides were identified within the 1H6 VH region, synthesized, and tested for MHC binding and immunogenicity. We show that germ line VH peptides, when presented by dendritic cells, are immunogenic in vitro and provoke a tumor-specific protective immune response in vivo. We conclude that (1) it is possible to induce a T-cell response to germ line VH peptides; (2) such peptides can be used to generate a B-cell tumor-specific vaccine; and (3) a vaccine targeting VH peptides expressed by the dominant dextran-specific B-cell clonotype had no effect upon the magnitude of the normal B-cell response to dextran.


2021 ◽  
Vol 12 ◽  
Author(s):  
Yang Liu ◽  
Yankang Wu ◽  
Bing Liu ◽  
Youpeng Zhang ◽  
Dan San ◽  
...  

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a global crisis; however, our current understanding of the host immune response to SARS-CoV-2 infection remains limited. Herein, we performed RNA sequencing using peripheral blood from acute and convalescent patients and interrogated the dynamic changes of adaptive immune response to SARS-CoV-2 infection over time. Our results revealed numerous alterations in these cohorts in terms of gene expression profiles and the features of immune repertoire. Moreover, a machine learning method was developed and resulted in the identification of five independent biomarkers and a collection of biomarkers that could accurately differentiate and predict the development of COVID-19. Interestingly, the increased expression of one of these biomarkers, UCHL1, a molecule related to nervous system damage, was associated with the clustering of severe symptoms. Importantly, analyses on immune repertoire metrics revealed the distinct kinetics of T-cell and B-cell responses to SARS-CoV-2 infection, with B-cell response plateaued in the acute phase and declined thereafter, whereas T-cell response can be maintained for up to 6 months post-infection onset and T-cell clonality was positively correlated with the serum level of anti-SARS-CoV-2 IgG. Together, the significantly altered genes or biomarkers, as well as the abnormally high levels of B-cell response in acute infection, may contribute to the pathogenesis of COVID-19 through mediating inflammation and immune responses, whereas prolonged T-cell response in the convalescents might help these patients in preventing reinfection. Thus, our findings could provide insight into the underlying molecular mechanism of host immune response to COVID-19 and facilitate the development of novel therapeutic strategies and effective vaccines.


2017 ◽  
Vol 35 (7_suppl) ◽  
pp. 69-69
Author(s):  
Claire Baniel ◽  
Jacquelyn A Hank ◽  
Emily I. Guy ◽  
Stephen D Gillies ◽  
Alan J. Korman ◽  
...  

69 Background: In a murine melanoma (MEL) model, we reported an in situ vaccination response to combined radiation (RT) and intra-tumor (IT) injection of anti-GD2 hu14.18-IL2 immunocytokine (IC). This treatment resulted in 71% complete regression of 5-week (~ 200mm3) tumors, a memory T cell response, and augmented response to systemic anti-CTLA-4 antibody (mAb) checkpoint blockade. We hypothesized that mice rendered disease-free (DF) by RT, IT-IC, and anti-CTLA-4 mAb might also exhibit a memory B cell response. Methods: C57BL/6 mice were implanted with 2x106 syngeneic, GD2+ B78 MEL cells and tumors developed for 5 weeks. Mice were treated with 12 Gy RT to this tumor followed by 5 daily IT injections of hu14.18-IL2 d6-10 after RT and IP injection of anti-CTLA-4 d3, 6, and 9 after RT. DF mice and naïve controls were challenged by subcutaneous implantation with 2x106 B78 MEL cells. Peripheral blood was collected from mice before and after B78 challenge and serum was evaluated for presence of tumor-specific mAbs using flow cytometry and ELISA. Results: Seventy-three percent of mice were rendered DF by treatment with RT, IT-hu14.18-IL2, and anti-CTLA-4. All of these (13/13) rejected a rechallange B78 implantation > 1 year later (range d378 – 511), whereas no naïve mice rejected B78 implantation (0/66). IgG from serum of DF mice bound selectively to B78 and parental GD2- B16 MEL cells and the level of this mAb response appeared to increase modestly d14 after B78 challenge. In naïve mice, a modest increase in tumor-specific mAb was identified between non-tumor implanted mice and d35 post-implantation mice (bearing tumors > 200mm3), however this level remained ~ 5 fold below that observed in DF mice prior to B78 rechallenge. In contrast, no appreciable mAb response was observed for unrelated syngeneic GD2+ Panc02 pancreatic tumor cells in serum of DF or naïve mice. Conclusions: We report an endogenous anti-tumor IgG humoral response in DF mice > 1 year after treatment with RT, IT-IC, and anti-CTLA-4 mAb, concurrent with demonstration of long lasting immune protection from re-challenge. Studies are underway to determine whether this response is involved in the therapeutic efficacy of this in situ vaccination regimen.


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