Pam2 lipopeptides enhance the immunosuppressive activity of monocytic myeloid-derived suppressor cells by STAT3 signal in chronic inflammation.

Chronic inflammation develops when the immune system is unable to clear a persistent insult. Unresolved chronic inflammation leads to immunosuppression to maintain the internal homeostatic conditions, which is mediated primarily by myeloid-derived suppressor cells (MDSCs). Toll-like receptors 2 (TLR2) has an important role in chronic inflammation and can be activated by a vast number and diversity of TLR2 ligands, for example Pam2CSK4. However, the regulatory effect of TLR2 signaling on MDSCs in chronic inflammation remains controversial. This study demonstrated that heat-killed Mycobacterium bovis BCG-induced pathology-free chronic inflammation triggered suppressive monocytic MDSCs (M-MDSCs) that expressed TLR2. Activation of TLR2 signaling by Pam2CSK4 treatment enhanced immunosuppression of M-MDSCs by upregulating inducible nitric oxide synthase (iNOS) activity and nitric oxide (NO) production partly through signal transducer and activator of transcription 3 (STAT3) activation. Thus, TLR2 has a fundamental role in promoting the MDSC-mediated immunosuppressive environment during chronic inflammation and might represent a potentially therapeutic target in chronic inflammation disease.

[Clinical Value of Immunophenotype Detection and DNA Ploid Analysis by Flow Cytometry for Non-Hodgkin's Lymphoma Patients].

OBJECTIVE: To explore the clinical values of detecting immunophenotype and analyzing DNA ploid by flow cytometry for patients with non-Hogkin's lymphoma (NHL). METHODS: Eighty NHL patients admitted in our hospital from August 2007 years to March 2015 Years were included in the observation group, 20 patients with reactive lymphoid hyperplasias were selectod as control group. The immunophenotypes were detected and the DNA ploid was analyzed by flow cytometry. RESULTS: The detected rate of DNA aneuploidy, DAN index (DI) and SPF in observation group were higher than those in control group, there was signifificant difference (P < 0.05). The SPF and DI in patients with NHL-I, NHL-II had no statistical difference as compared with that in control group (P > 0.05); but the SPF and DI in pateints with NHL-III and patients with NHL-IV showed statistical significance as compared with that in control group (P < 0.05). The SPF and DI in patients with low malignancy group and middle malignancy group showed statistical significance as compared with control group (P < 0.05). The SPF and DI in middle malignancy group had statistical significance as compared with that in low malignancy group (P < 0.05). CONCLUSION: the immunophenotype detection and DNA ploid analysis by flow cytometry can reflect the tumor proliferation and deterioration of patients with Non-Hogkin's lymphoma, predicting the prognosis.