Polyclonal activation of immature B cells by preactivated T cells: the role of IL-4 and CD40 ligand

1993 ◽  
Vol 5 (11) ◽  
pp. 1445-1450 ◽  
Author(s):  
Robert D. Brines ◽  
Gerry G. B. Klaus
1991 ◽  
Vol 173 (6) ◽  
pp. 1433-1439 ◽  
Author(s):  
R H Lin ◽  
M J Mamula ◽  
J A Hardin ◽  
C A Janeway

A novel mechanism for breaking T cell self tolerance is described. B cells induced to make autoantibody by immunization of mice with the non-self protein human cytochrome c can present the self protein mouse cytochrome c to autoreactive T cells in immunogenic form. This mechanism of breaking T cell self tolerance could account for the role of foreign antigens in breaking not only B cell but also T cell self tolerance, leading to sustained autoantibody production in the absence of the foreign antigen.


PEDIATRICS ◽  
1994 ◽  
Vol 94 (2) ◽  
pp. 280-280
Author(s):  
Arden Levy ◽  
Andrew Liu

Purpose of the Studies. Hyper-IgM immunodeficiency is characterized by recurrent bacterial infections, normal or elevated IgM, and markedly decreased IgG, IgA, and IgE. Previous research suggested that the T cells of these patients are defective in their ability to help B cells make functional antibody. CD40 ligand (CD4OL) is a membrane glycoprotein on activated T helper cells and binds the CD40 molecule expressed on B cells, and induces proliferation and immunoglobulin class switching (in conjunction with IL-4). The gene for the CD4OL has been mapped to position q26.3-q27.1 on chromosome X (same as the Hyper-IgM gene and the area of isotype switching). Several research groups sought to determine if the immunodeficiency in Hyper-IgM patients is due to defective CD4OL. Findings. The five papers listed above document the work of different research groups that simultaneously found abnormalities in the CD4OL gene in a total of 16 patients with X-linked Hyper-IgM syndrome. Different mutations of the CD4OL gene have been discovered, including point mutations, deletions, and nonsense sequences. Mutant version of CD4OL taken from Hyper IgM patients were unable to "help" B cells in vitro. Thus, deficient CD40/CD40L interactions between B and T cells results in severely impaired immunity. Restricted CD40L gene expression to T cells may ultimately allow gene therapy as treatment. Reviewers' Comments. A concise editorial by Jean Marx entitled "Cell Communication Failure Leads to Immune Disorder" describes this landmark research and accompanies the Spriggs article in the February 12th issue of Science (pp. 896-897). This discovery may not only lead to treatment of this disorder, but also modification of other less favorable immune responses.


PEDIATRICS ◽  
1994 ◽  
Vol 94 (2) ◽  
pp. 280-280
Author(s):  
Arden Levy ◽  
Andrew Liu

Purpose of the Studies. Hyper-IgM immunodeficiency is characterized by recurrent bacterial infections, normal or elevated IgM, and markedly decreased IgG, IgA, and IgE. Previous research suggested that the T cells of these patients are defective in their ability to help B cells make functional antibody. CD40 ligand (CD4OL) is a membrane glycoprotein on activated T helper cells and binds the CD40 molecule expressed on B cells, and induces proliferation and immunoglobulin class switching (in conjunction with IL-4). The gene for the CD4OL has been mapped to position q26.3-q27.1 on chromosome X (same as the Hyper-IgM gene and the area of isotype switching). Several research groups sought to determine if the immunodeficiency in Hyper-IgM patients is due to defective CD4OL. Findings. The five papers listed above document the work of different research groups that simultaneously found abnormalities in the CD4OL gene in a total of 16 patients with X-linked Hyper-IgM syndrome. Different mutations of the CD4OL gene have been discovered, including point mutations, deletions, and nonsense sequences. Mutant version of CD4OL taken from Hyper IgM patients were unable to "help" B cells in vitro. Thus, deficient CD40/CD40L interactions between B and T cells results in severely impaired immunity. Restricted CD40L gene expression to T cells may ultimately allow gene therapy as treatment. Reviewers' Comments. A concise editorial by Jean Marx entitled "Cell Communication Failure Leads to Immune Disorder" describes this landmark research and accompanies the Spriggs article in the February 12th issue of Science (pp. 896-897). This discovery may not only lead to treatment of this disorder, but also modification of other less favorable immune responses.


2008 ◽  
Vol 32 (4) ◽  
pp. 287-293 ◽  
Author(s):  
Michele Bolan ◽  
Daniele de Almeida Lima ◽  
Cláudia Pinto Figueiredo ◽  
Gabriella Di Giunta ◽  
Maria José de Carvalho Rocha

BACKGROUND: The periapical lesion is the result of a local inflammatory reaction caused by bacteria and its products present on the root canal. The interaction between inflammatory cells and bacteria elicit both specific and non-specific immune responses. OBJETIVE: Due to the lack of studies evaluating the role of the immune system in periapical lesions of primary teeth and considering the potentially systemic effects that these infections can cause in children, especially because of the immaturity of their immune system, we sought to evaluate the presence of T cells, B cells and macrophages on periradicular lesions in primary teeth. STUDY DESIGN: 14 periradicular lesions were analyzed. The immunohistochemistry technique was performed using CD45RO, CD20, CD68 monoclonal antibodies aiming to identify T cells, B cells and macrophages, respectively. Cells were quantified by microscopic analysis of histological sections. RESULTS: Mean percentage of positive cells CD45RO was 11.76; CD20 was 5.25; CD68 was 10.92. Our results showed that T and B cells and macrophages comprise the majority of the inflammatory infiltrate. CONCLUSION: We concluded that both humoral and cell mediated immune reactions take place in periradicular lesions of primary teeth. The immune system plays an important role on the periradicular inflammatory processes in primary teeth.


Blood ◽  
1997 ◽  
Vol 89 (12) ◽  
pp. 4415-4424 ◽  
Author(s):  
Jon Lømo ◽  
Heidi Kiil Blomhoff ◽  
Sten Eirik Jacobsen ◽  
Stanislaw Krajewski ◽  
John C. Reed ◽  
...  

Abstract Interleukin-13 (IL-13) is a novel T-cell–derived cytokine with IL-4–like effects on many cell types. In human B lymphocytes, IL-13 induces activation, stimulates proliferation in combination with anti-IgM or anti-CD40 antibodies, and directs Ig isotype switching towards IgE and IgG4 isotypes. We show here that IL-13 also regulates human B-cell apoptosis. IL-13 reduced spontaneous apoptosis of peripheral blood B cells in vitro, as shown by measurement of DNA fragmentation using the TUNEL and Nicoletti assays. The inhibition of cell death by IL-13 alone was significant but modest, but was potently enhanced in combination with CD40 ligand (CD40L), a survival stimulus for B cells by itself. Interestingly, IL-13 increased the expression of CD40 on peripheral blood B cells, providing a possible mechanism for the observed synergy. IL-13 alone was a less potent inhibitor of apoptosis than IL-4. Moreover, there was no additive effect of combining IL-4 and IL-13 at supraoptimal concentrations, which is consistent with the notion that the IL-4 and IL-13 binding sites share a common signaling subunit. The combination of IL-13 with CD40L augmented the expression of the Bcl-2 homologues Bcl-xL and Mcl-1, suggesting this as a possible intracellular mechanism of induced survival. By contrast, levels of Bcl-2, and two other Bcl-2 family members, Bax and Bak, remained unaltered. Given the importance of the CD40-CD40L interaction in B-cell responses, these results suggest a significant role of IL-13 in the regulation of B-cell apoptosis.


2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Fei Fei Guo ◽  
Jiu Wei Cui

Earlier studies on elucidating the role of lymphocytes in tumor immunity predominantly focused on T cells. However, the role of B cells in tumor immunity has increasingly received better attention in recent studies. The B cells that infiltrate tumor tissues are called tumor-infiltrating B cells (TIBs). It is found that TIBs play a multifaceted dual role in regulating tumor immunity rather than just tumor inhibition or promotion. In this article, latest research advances focusing on the relationship between TIBs and tumor complexity are reviewed, and light is shed on some novel ideas for exploiting TIBs as a possible tumor biomarker and potential therapeutic target against tumors.


Endocrine ◽  
2020 ◽  
Vol 70 (3) ◽  
pp. 593-606
Author(s):  
Pedro Marques ◽  
Sayka Barry ◽  
Eivind Carlsen ◽  
David Collier ◽  
Amy Ronaldson ◽  
...  

Abstract Purpose Angiogenesis has been studied in pituitary neuroendocrine tumours (PitNETs), but the role of the tumour microenvironment (TME) in regulating PitNET angiogenesis remains unknown. We aimed to characterise the role of TME components in determining the angiogenetic PitNET profile, focusing on immune cells and tumour-derived cytokines. Methods Immune cells were studied by immunohistochemistry in 24 human PitNETs (16 non-functioning-PitNETs (NF-PitNETs) and 8 somatotrophinomas): macrophages (CD68, CD163, HLA-DR), cytotoxic (CD8) and T helper (CD4) lymphocytes, regulatory T cells (FOXP3), B cells (CD20) and neutrophils (neutrophil elastase); endothelial cells were assessed with CD31. Five normal pituitaries (NP) were included for comparison. Microvessel density and vascular morphology were estimated with ImageJ. The cytokine secretome from these PitNETs were assessed on culture supernatants using a multiplex immunoassay panel. Results Microvessel density/area was higher in NP than PitNETs, which also had rounder and more regular vessels. NF-PitNETs had vessels of increased calibre compared to somatotrophinomas. The M2:M1 macrophage ratio correlated with microvessel area. PitNETs with more CD4+ T cells had higher microvessel area, while tumours with more FOXP3+ cells were associated with lower microvessel density. PitNETs with more B cells had rounder vessels. Of the 42 PitNET-derived cytokines studied, CCL2, CXCL10 and CX3CL1 correlated with microvessel density and vessel architecture parameters. Conclusions M2 macrophages appear to play a role in PitNET neovascularisation, while B, CD4+ and FOXP3+ lymphocytes, as well as non-cellular TME elements such as CCL2, CXCL10 and CX3CL1, may also modulate the angiogenesis of PitNETs.


1975 ◽  
Vol 142 (5) ◽  
pp. 1165-1179 ◽  
Author(s):  
S K Pierce ◽  
N R Klinman

The ability of T cells to enhance the response of syngeneic and allogeneic B cells to thymus-dependent hapten-carrier conjugates was analyzed. This analysis was carried out on individual primary B cells in splenic fragment cultures derived from irradiated reconstituted mice. This system has several advantages: (a) the response of the B cells is entirely dependent on carrier priming of the irradiated recipient; (b) this B-cell response can be quantitated in terms of the number of responding cells; and (c) very small B-cell responses can be readily detected and analyzed. The results indicate that the majority of hapten-specific B cells were stimulated in allogeneic and syngeneic recipients only if these recipients were previously carrier primed. The number of B cells responding in carrier-primed allogeneic recipients was 60-70% of that in syngeneic carrier-primed recipients. The antibody-forming cell clones resulting from B cells stimulated in the allogeneic environment produced small amounts of antibody and antibody solely of the IgM immunoglobulin class, while the larger responses in syngeneic recipients were predominantly IgG1 or IgM plus IgG1. The capacity of collaborative interactions between carrier-primed T cells and primary B cells to yield IgG1 antibody-producing clones was shown to be dependent on syngeny between these cells in the H-2 gene complex. It is concluded that: (a) B cells can be triggered by T-dependent antigens to clone formation through collaboration with T cells which differ at the H-2 complex as long as these T cells recognize the antigen; (b) the immunoglobulin class produced by the progeny of stimulated B cells generally depends on the nature of the stimulatory event rather than the nature of the B cell itself; and (c) stimulation to IgG1 production is dependent on syngeny between the collaborating T and B cells probably within the Ir-1A region. The role of the Ia antigens in the formation of IgG1-producing clones is not yet clear; Ia identity could permit IgG1 production or, conversely, nonidentity of Ia could induce all allogeneic interactions which prohibit IgG1 production.


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