Journal: PLoS ONE

Article Title: Impaired Clearance of Early Apoptotic Cells Mediated by Inhibitory IgG Antibodies in Patients with Primary Sjögren's Syndrome

doi: 10.1371/journal.pone.0112100

Figure Lengend Snippet: The aberrant uptake of apoptotic cells by blood-borne phagocytes largely resides in the patients' sera. A. Significantly decreased ApoCell-phagocytosis by PB monocytes in SS and SLE patients, but not in RA. B–C. The ApoCell-phagocytosis index values observed in SS and SLE patients correlated inversely with the disease activity indices of these diseases. D. Decreased ApoCell-phagocytosis by MDM in SS and SLE patients. E. Cross-admixture experiments illustrating the significantly reduced capacity of sera from SS and SLE patients to support ApoCell-phagocytosis by normal peripheral blood (PB) monocytes, in contrast to sera from HBD and from RA patients. In panels A, C and D the horizontal lines indicate the median levels in each group, whereas the numbers in boxes indicate the percentages of individuals with decreased ApoCell-phagocytosis, as defined by the presence of ApoCell-PhI values that were two standard deviations below the corresponding mean of HBD. Statistically significant comparisons of patient groups to HBD are shown. In panel B, the mean ApoCell-PhI values of SS-derived MDM were marginally different compared to MDM (p = 0.06).

Article Snippet: ApoCell-phagocytosis and MB-phagocytosis were comparatively assessed by flow cytometry in peripheral blood specimens and monocyte-derived macrophage (MDM) preparations from healthy blood donors (HBD) and consecutive SS, SLE and rheumatoid arthritis (RA) patients.

Techniques: Activity Assay, Derivative Assay

Journal: PLoS ONE

Article Title: Impaired Clearance of Early Apoptotic Cells Mediated by Inhibitory IgG Antibodies in Patients with Primary Sjögren's Syndrome

doi: 10.1371/journal.pone.0112100

Figure Lengend Snippet: Purified serum IgG preparations from SS and SLE patients display inhibitory activity on ApoCell-phagocytosis by healthy MDM that correlates with its binding activity to early apoptotic cells. A. Purified serum IgG preparations from SS and SLE patients (but not RA) display significantly increased binding to early apoptotic cells. Binding index was normalized and expressed as fold increase over the binding of a purified IgG preparation from a HBD used in all experiments. B–D . Cross-admixture ApoCell-phagocytosis experiments demonstrating that the pretreatment of early apoptotic cells with purified serum IgG preparations derived from SS and SLE (but not from RA) results in decreased ApoCell-phagocytosis by healthy MDM, as compared to treatment with IgG from HBD. In B , data are expressed as percent of baseline ApoCell-phagocytosis values (e.g. treatment of apoptotic cells with PBS only, considered as 100%). Similar results were obtained by slightly different experimental setups assaying the ingestion of CFSE-labelled IgG-pretreated apoptotic cells by electronically gated CD14-stained MDM in dual-color flow cytometry ( C ; representative results from 3 independent experiments) or the uptake of pHrodo-SE-labelled apoptotic cells in single-color flow cytometry ( D ). E . Highly significant inverse correlation between the rates of ApoCell-phagocytosis obtained by the various purified serum IgG preparations used (shown in A) and the levels of anti-ApoCell antibodies in those preparations (shown in A).

Article Snippet: ApoCell-phagocytosis and MB-phagocytosis were comparatively assessed by flow cytometry in peripheral blood specimens and monocyte-derived macrophage (MDM) preparations from healthy blood donors (HBD) and consecutive SS, SLE and rheumatoid arthritis (RA) patients.

Techniques: Purification, Activity Assay, Binding Assay, Derivative Assay, Staining, Flow Cytometry