ABSTRACT
AIM: To study the effect of tick anticoagulant peptide-staphylococcal superantigen like protein 5 (TAP-SSL5), an anti-inflammatory and anticoagulant fusion protein , on the binding of activated platelets to human lym-phocytes.METHODS:Human periphery lymphocytes were isolated by magnetic activated cell sorting (MACS).The toxic-ity of TAP-SSL5 on the viability of Jurkat cell was assessed by CCK-8 assay.Flow cytometry was applied to detect the ex-pression of CD162 (PSGL-1) on the Jurkat cells (human peripheral blood leukemia T lymphocyte cell line ) and the inhibi-tory effect of TAP-SSL5 on the binding of mouse anti-human CD162 monoclonal antibody (KPL-1) to Jurkat cells.Platelets were activated by ADP at concentration of 20μmol/L, the binding rates of activated platelets to Jurkat cells or human lym-phocytes were assayed by flow cytometry .RESULTS:The concentration of TAP-SSL5 below 30 mg/L didn’ t affect the vi-ability of Jurkat cells .TAP-SSL5 at 10 mg/L competitively inhibited KPL-1 binding to Jurkat cells .The binding rates of activated platelets to Jurkat cells or lymphocytes were (11.86 ±4.49)% and (8.32 ±1.00)%, respectively, which de-creased to (6.73 ±2.71)%and (5.51 ±0.70)%after the Jurkat cells and lymphocytes were pre-incubated with 10 mg/L TAP-SSL5 (P <0.05).CONCLUSION:TAP-SSL5 binds to PSGL-1 expressed on lymphocyte surface and directly in-hibits the binding of activated platelets to human lymphocytes , which may be one of the anti-inflammatory mechanisms of TAP-SSL5.
ABSTRACT
Objective To explore the distribution of inflam m atory cells and positive expression of P-se-lectin glycoprotein ligand-1 (PSG L-1) in infant brainstem tissue from hand-foot-m outh disease related fatal brainstem encephalitis. Methods Tw enty brainstem sam ples from infants suffered from brainstem en-cephalitis w ere collected as the experim ental group. Ten brainstem sam ples from infants died of non-brain diseases and injuries w ere collected as the control group. The distribution of inflam m atory cells and the expression of PSG L-1 in the tw o groups w ere exam ined by im m unohistochem ical m ethod. The characteristics of the positive cells w ere observed. Results In brainstem tissue of the experim ental group, there w ere sleeve infiltrations of inflam m atory cells around the vessels and in the glial nodule. Microglia was the m ost and following was neutrophils around the vessels and in the glial nodule. There was a significant statistical difference am ong m icroglias, neutrophils and lym phocytes (P<0.05). There was no sleeve infiltration in the control group. PSG L-1 protein was expressed w idely in inflam m atory cells in the experim ental group, especially in the inflam m atory cells around the vessels and in the glial nodule. B ut PSG L-1 positive staining could be observed significantly less in the control group com paring with the experim ental group (P<0.05). Conclusion Microglia is the m ain type of inflam m atory cells involved in the progress of the fatal disease. Moreover, PSG L-1 could participate in the pathogenesis of hand-foot-m outh disease related fatal brainstem encephalitis.
ABSTRACT
Objective To understand the correlation of enterovirus 71 (EV71), P-selectin glycoprotein ligand-1 (PSG L-1), and scavenger receptor B2 (SCARB2) and to explore the possible pathway and mechanismof EV71 infection by observing the expression of EV71, PSG L-1 and SCARB2 in tissues of infants with brain stemencephalitis. Methods T he organs and tissues of infants with EV71-VP1 positivi-ty in their brain stems were chosen. Expression and distribution of EV71-VP1, PSG L-1, and SCARB2 were detected and compared by immunohistochemistry. Results Strong staining of EV71-VP1 was ob-served in the neuron, glial cells, the inflammatory cells of perivascular cuffing, parietal cells of the gas-tric fundus gland while alveolar macrophages, intestinal gland epitheliumcells, mucosa lymphoid nodule and lymphocyte of palatine tonsil showed moderate staining and weak staining were displayed in mesen-teric lymph nodes and lymphocyte of spleen. PSG L-1 expression was detected in parietal cells of the gastric fundus gland, tonsillar crypt squamous epithelium, alveolar macrophages and leukocytes in each tissue. SCARB2 expression was observed in all the above tissues except the intestines and spleen. Con-clusion T he distribution of EV71 correlates with SCARB2 expression. SCARB2 plays an important role in virus infection and replication. Stomach may be an important site for EV71 replication.
ABSTRACT
Objective PSGL-1 is specifically expressed in leucocytes.The aim of this study was to explore the changes of myeloid-derived suppressor cells (MDSCs) in the spleen and bone marrow in PSGL-1-deficient mice.Methods PSGL-1 -/-mice were used in the experiment.After identification of the offsprings, flow cytometry was used to test the expression of CD11b and Gr-1 in C57 and PSGL-1 -/-mice.Results Compared with the C57 mice, the expression of MDSCs was up-regulated in the PSGL-1-deficient mice ( P <0.001).Conclusion The expression of MDSCs is upregulated in PSGl-1-deficient mice.