scholarly journals Cyclic ADP-ribose is a second messenger in the lipopolysaccharide-stimulated proliferation of human peripheral blood mononuclear cells

2003 ◽  
Vol 375 (2) ◽  
pp. 395-403 ◽  
Author(s):  
Santina BRUZZONE ◽  
Antonio DE FLORA ◽  
Cesare USAI ◽  
Richard GRAEFF ◽  
Hon Cheung LEE
Keyword(s):  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Second Messenger ◽  
Immune Recognition ◽  
Adp Ribosyl Cyclase ◽  
T Lymphocyte Proliferation ◽  
Cyclic Adp Ribose ◽  
Membrane Bound

Cyclic ADP-ribose (cADPR), a universal calcium mobilizer from intracellular stores, was recently demonstrated to stimulate proliferation of various cell types. The role of cADPR in a specific process of monocyte- and plasma-mediated activation of T-lymphocytes by lipopolysaccharide (LPS) was addressed using human mononuclear cells from peripheral blood (PBMCs). Incubation of PBMCs with 0.1 μg/ml of LPS for 24 h provided a doubling in the intracellular levels of cADPR as compared with unstimulated PBMCs. The cADPR increase was abolished either by prior removal of monocytes or by pre-incubating a whole PBMC population with a monoclonal antibody against the monocyte marker CD14. The increased concentrations of intracellular cADPR elicited by LPS stimulation were paralleled by significant increases in NAD+ levels and in the activities of ectocellular and membrane-bound fractions of ADP-ribosyl cyclase/cADPR hydrolase activities. A cytosolic ADP-ribosyl cyclase was also detectable in PBMCs and its activity was comparably enhanced by LPS stimulation. This soluble cyclase is distinguished from the membrane-bound cyclase by both substrate and inhibitor sensitivities. LPS-stimulated PBMCs showed 2–3-fold increases of intracellular calcium ([Ca2+]i), and these changes were prevented completely by the cADPR antagonist 8-Br-cADPR and by ryanodine. Both compounds, and the cyclase inhibitor nicotinamide, significantly inhibited the T-lymphocyte proliferation induced by LPS in PBMCs. These results demonstrate that cADPR plays a role of second messenger in the adaptive immune recognition process of LPS-stimulated proliferation of PBMCs.

Low Density Granulocytes in Patients after Allogeneic Hematopoietic Stem Cells Transplantation (allo-HSCT): A Distinct Class of Neutrophils in Systemic Alloimmunity

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 4614-4614
Author(s):  
Ekaterina Mikhaltsova ◽  
Valeri G. Savchenko ◽  
Larisa A. Kuzmina ◽  
Mikhail Drokov ◽  
Vera Vasilyeva ◽  
...  
Keyword(s):  
Lupus Erythematosus ◽  
Peripheral Blood ◽  
Hematological Malignancies ◽  
Mononuclear Cells ◽  
Conflicts Of Interest ◽  
Human Peripheral Blood ◽  
Unrelated Donor ◽  
Low Density ◽  
Hematopoietic Stem

Abstract Introduction It's generally considered that all alloimmune process such as acute graft-versus host disease (aGVHD) after allo-HSCT are mostly controlled by lymphocytes. The role of neutrophils in systemic alloimmunity after allo-HSCT is still illusive. In 1987 a distinct subset of proinflammatory, low-density granulocytes (LDGs) isolated from the peripheral blood mononuclear cell fractions of patients with system lupus erythematosus has been described. There is no LDG's in healthy donors. While the origin and role of LDGs still needs to be fully characterized, we try to describe this population in patients with hematological malignancies after allo-HSCT Patients and methods. Peripheral blood samples were collected in EDTA-tubes before allo-HSCT, on day +30,+60,+90 after allo-HSCT and at day of aGVHD from 47 patients with hematological malignancies (AML=22, ALL n=17, LPD=3, MDS =2; CML=2; 17 with active disease, 30 - in CR) after allo-HSCT (from matched unrelated donor n=34, from matched related donor n=13; MAC = 13, RIC=34). Isolation of mononuclear cells from human peripheral blood was made by standard protocol using Lympholyte®-M Cell Separation Media (Cedarlane Labs). The anti-CD66b-PE (Biolegend, USA) antibodies and FSC/SSC were used to determine LDGs cells as FSChigh \SSChigh \CD66b+. 100000 of cells were analyzed on a BD FACSCanto II (Becton Dickinson, USA). Results. Results of blood evaluation of 47 patients with hematological malignancies, whose blood was examined after allo-HSCT presented in table 1. Conclusion Despite the fact that we don't get significant differences. LDG's detection in allo-HSCT patients need further investigation. Table 1. Incidence of LDG after allo-HSCT in patients with and without aGVHD Table 1. Incidence of LDG after allo-HSCT in patients with and without aGVHD Disclosures No relevant conflicts of interest to declare.

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