scholarly journals The properties of human CD40-activated B cells as antigen-presenting cells are not affected by PGE2

2012 ◽  
Vol 29 (3) ◽  
pp. 1061-1065 ◽  
Author(s):  
ALEXANDER SHIMABUKURO-VORNHAGEN ◽  
ANDREAS DRAUBE ◽  
TANJA LIEBIG ◽  
ALEXEY POPOV ◽  
ACHIM ROTHE ◽  
...  
Blood ◽  
2004 ◽  
Vol 104 (9) ◽  
pp. 2801-2809 ◽  
Author(s):  
Matthias Gunzer ◽  
Carsten Weishaupt ◽  
Anja Hillmer ◽  
Yasmin Basoglu ◽  
Peter Friedl ◽  
...  

Abstract For activation T cells engage antigen-presenting cells (APCs) in lymphatic tissues. The contact duration and kinetics (static versus dynamic) vary considerably in different model systems; however, it is unclear whether T cells, APCs, or the environment are responsible for the observed discrepancies. Using 3-D collagen matrices as structural scaffold, we directly compared the kinetics of T-cell engagement and activation by functionally major APC types, ie, dendritic cells (DCs) and resting or activated B cells. Resting B cells engaged T cells in long-lived (several hours), adhesive, and leukocyte function-associated antigen-1 (LFA-1)-dependent conjugates in 3-D collagen as well as in intact lymph nodes in vivo. DCs and preactivated B cells, however, supported predominantly dynamic, short-lived (minutes), and sequential contacts to T cells that were dependent on high cytoskeletal activity of the APCs but could not be inhibited by anti-LFA-1 treatment. Naive T cells were most strongly activated by DCs and activated B cells, whereas resting B cells were 100-fold less efficient to induce T-cell proliferation. Thus, in the same 3-D environment, naive T cells respond with a spectrum of different interaction modes dependent on the type and activation state of the APCs. Thereby, more dynamic interaction kinetics is positively correlated with higher T-cell priming efficiency. (Blood. 2004;104: 2801-2809)


2013 ◽  
Vol 12 (6) ◽  
pp. 631-637 ◽  
Author(s):  
Kerstin Wennhold ◽  
Alexander Shimabukuro-Vornhagen ◽  
Sebastian Theurich ◽  
Michael von Bergwelt-Baildon

Blood ◽  
2002 ◽  
Vol 99 (9) ◽  
pp. 3319-3325 ◽  
Author(s):  
Michael S. von Bergwelt-Baildon ◽  
Robert H. Vonderheide ◽  
Britta Maecker ◽  
Naoto Hirano ◽  
Karen S. Anderson ◽  
...  

Abstract CD40 engagement is the major signal that induces B cells to efficiently present antigen to T cells. We previously demonstrated that human peripheral blood–derived CD40-activated B cells (CD40–B cells) function as antigen-presenting cells (APCs). Here, we have established a culture system to generate these APCs under clinically applicable conditions using guanylic acid–grade soluble trimeric CD40 ligand. To monitor APC function and antigen loading for these cells, simple and efficient quality control assays have been developed. Using this approach, we demonstrate that CD40–B cells from healthy donors and cancer patients are fully functional and equally expanded in long-term cultures. These B cells boost robust memory T-cell responses, but more importantly, they also prime naive T-cell responses against neoantigens ex vivo. CD40–B cells overcome current obstacles, such as the difficulty of isolation, generation, and long-term expansion observed with other APCs. Therefore, they are an excellent source of professional APCs for immune assessment, antigen discovery, and antigen-specific immunotherapy.


1993 ◽  
Vol 178 (6) ◽  
pp. 2055-2066 ◽  
Author(s):  
M H Kosco-Vilbois ◽  
D Gray ◽  
D Scheidegger ◽  
M Julius

This study was designed to investigate whether follicular dendritic cells (FDC) can activate B cells to a state in which they can function as effective antigen-presenting cells (APC). High buoyant density (i.e., resting) B cells specific for 2,4-dinitro-fluorobenzene (DNP) were incubated with DNP-ovalbumin (OVA) bearing FDC, after which their capacity to process and present to an OVA-specific T cell clone was assessed. The efficacies of alternative sources of antigen and activation signals in the induction of B cell APC function were compared with those provided by FDC. Only FDC and Sepharose beads coated with anti-immunoglobulin (Ig)kappa monoclonal antibody provided the necessary stimulus. FDC carrying inappropriate antigens also induced B cell APC function in the presence of exogenous DNP-OVA. However, in circumstances where soluble DNP-OVA was limiting, FDC bearing complexes containing DNP, which could crosslink B cell Ig receptors, induced the most potent APC function. Analysis by flow cytometry revealed that within 24 h of coculture with FDC, a significant percentage of B cells increased in size and expressed higher levels of major histocompatibility complex class II. By 48 h, an upregulation of the costimulatory molecule, B7/BB1, occurred, but only when exposed to the FDC bearing DNP. Taken together, the results demonstrate that FDC have the capacity to activate resting B cells to a state in which they can function as APC for T cells. The stimuli that FDC provide may include: (a) an antigen-dependent signal that influences the upregulation of B7/BB1; and (b) possibly a signal independent of crosslinking mIg that results in Ig internalization. The relevance of these findings to the formation of germinal centers and maintenance of the humoral response is discussed.


Vaccines ◽  
2018 ◽  
Vol 6 (4) ◽  
pp. 75 ◽  
Author(s):  
Angita Shrestha ◽  
Jean-Remy Sadeyen ◽  
Munir Iqbal

Avian viral diseases including avian influenza, Marek’s disease and Newcastle disease are detrimental to economies around the world that depend on the poultry trade. A significant zoonotic threat is also posed by avian influenza viruses. Vaccination is an important and widely used method for controlling these poultry diseases. However, the current vaccines do not provide full protection or sterile immunity. Hence, there is a need to develop improved vaccines. The major aim of developing improved vaccines is to induce strong and specific humoral and cellular immunity in vaccinated animals. One strategy used to enhance the immunogenicity of vaccines is the selective delivery of protective antigens to antigen-presenting cells (APCs) including dendritic cells, macrophages and B cells. APCs have a central role in the initiation and maintenance of immune responses through their ability to capture, process and present antigens to T and B cells. Vaccine technology that selectively targets APCs has been achieved by coupling antigens to monoclonal antibodies or ligands that are targeted by APCs. The aim of this review is to discuss existing strategies of selective delivery of antigens to APCs for effective vaccine development in poultry.


1998 ◽  
Vol 187 (10) ◽  
pp. 1611-1621 ◽  
Author(s):  
Sarah E. Townsend ◽  
Christopher C. Goodnow

Antigen-specific B cells are implicated as antigen-presenting cells in memory and tolerance responses because they capture antigens efficiently and localize to T cell zones after antigen capture. It has not been possible, however, to visualize the effect of specific B cells on specific CD4+ helper T cells under physiological conditions. We demonstrate here that rare T cells are activated in vivo by minute quantities of antigen captured by antigen-specific B cells. Antigen-activated B cells are helped under these conditions, whereas antigen-tolerant B cells are killed. The T cells proliferate and then disappear regardless of whether the B cells are activated or tolerant. We show genetically that T cell activation, proliferation, and disappearance can be mediated either by transfer of antigen from antigen-specific B cells to endogenous antigen-presenting cells or by direct B–T cell interactions. These results identify a novel antigen presentation route, and demonstrate that B cell presentation of antigen has profound effects on T cell fate that could not be predicted from in vitro studies.


1994 ◽  
Vol 179 (1) ◽  
pp. 249-258 ◽  
Author(s):  
K M Gilbert ◽  
W O Weigle

Antigen presentation by resting splenic B cells has been shown previously to induce T helper 1 cell (Th1) anergy. In contrast to expectations, it was found here that B cells treated with F(ab')2 goat anti-mouse immunoglobulin (IgM) for 24 or 48 h also presented antigen (Ag) to Th1 cells in a manner that induced dramatic Ag-specific proliferative inactivation. The tolerogenicity of the anti-Ig-treated B cells was consistent with the observation that these B cells were only slightly more efficient than resting B cells in stimulating human gamma globulin (HGG)-induced proliferation of HGG-specific Th1 cells in primary cultures. The activated B cells were, however, more efficient than resting B cells in stimulating a primary mixed leukocyte reaction, and exhibited increased expression of major histocompatibility complex class II molecules, RL388 Ag and transferrin receptor. In addition, unlike resting B cells, which expressed little detectable B7, anti-Ig-treated B cells expressed high levels of B7. The functional capacity of the B7 expressed on the activated B cells was demonstrated by the fact that the Ag-presenting capacity of these B cells was inhibited by the addition to culture of CTLA4Ig, a soluble receptor for B7. It is unlikely that the tolerogenicity of the activated B cells was due to an inability of the Th1 cells to respond to B7 signals; the Th1 clones used in the experiments, unlike the Th2 clones tested, expressed CD28, the ligand for B7. In addition, anti-CD28 monoclonal antibody inhibited the induction of Th1 cell anergy when added to cultures of Th1 cells and Ag-pulsed fixed antigen-presenting cells. Taken together, the results indicate that B cells, even when activated, do not satisfy the costimulatory requirements of the Th1 cells used here, and therefore can present Ag in a tolerogenic fashion to Th1 cells. The costimulator deficiency of activated B cells may reflect an inadequacy in the level of B7 expressed or a lack of some other molecule.


Sign in / Sign up

Export Citation Format

Share Document