[Polymorphonuclear leukocytes decrease the immunostimulatry capacity of human dendritic cells]
Paulo Maffia1, Sandra Zittermann, María Lucila Scimone
1Laboratorio de Inmunogenética, Hospital de Clínicas José de San Martín y Departamento de Microbiología, Parasitología e Inmunología, Facultad de Medicina, Universidad de Buenos Aires, Argentina.
Abstract:
The aim of this work was to evaluate the ability of polymorphonuclear leukocytes (PMNL) to modulate the function of dendritic cells (DCs). Human DCs were used to analyze the effect of PMNL on DCs. The allostimulatory proliferation of T cells induced by DCs incubated with PMNL was lower (42 +/- 14%, n:8, p<0.05) compared with untreated DCs. The decreased proliferation correlated with lower IFNgamma production (DCs: 781 +/- 3 pg/ ml; DCs-CS: 343 +/- 178 pg/ml, p<0.05). The same effect was observed in an antigen specific assay. However, the effect was not observed when PMNL where incubated with mature DCs. Indeed, the effect of PMNL was partially reverted with serine proteases inhibitors. Overall, these results suggest that PMNL modulates DCs activity by serine proteases.
Insights
Polymorphonuclear leukocytes (PMNL) can suppress T cell proliferation and IFN-gamma production by dendritic cells (DCs). This PMNL modulation of DCs is mediated by serine proteases and is less effective on mature DCs.
Area of Science:
- Immunology
- Cell Biology
Context:
- Dendritic cells (DCs) are crucial antigen-presenting cells that initiate immune responses.
- Polymorphonuclear leukocytes (PMNL) are key innate immune cells involved in inflammation and host defense.
Purpose:
- To investigate the modulatory effect of PMNL on the function of human dendritic cells (DCs).
- To determine the mechanisms underlying PMNL-induced modulation of DC function.
Summary:
- PMNL significantly reduced the allostimulatory capacity of DCs, leading to decreased T cell proliferation and lower IFN-gamma production.
- This suppressive effect was observed in both allogeneic and antigen-specific assays.
- The inhibitory effect of PMNL on DCs was partially reversed by serine protease inhibitors, suggesting a role for these enzymes.
Impact:
- These findings reveal a novel mechanism by which PMNL can influence adaptive immune responses by modulating DC function.
- Understanding this interaction is crucial for developing immunotherapies and managing inflammatory conditions.
