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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Antibodies, Antibodies, Antinuclear, Calcium, Case-Control Studies, Cell Survival, DNA, Dose-Response Relationship, Drug, HEK293 Cells, Humans, Immunoglobulin G, Kidney, Lupus Erythematosus, Systemic, Receptors, N-Methyl-D-Aspartate, Zinc.
user
Does nR2-reactive antibody decrease cell viability through augmentation of Ca ( 2+ ) influx in systemic lupus erythematosus? Context: Anti-N-methyl-D-aspartate (anti-NMDA) receptor subunit NR2-reactive antibody may play a crucial role in neuronal manifestations of systemic lupus erythematosus (SLE). However, how NR2-reactive antibody acts as a critical modulator of the NMDA receptor is unknown. This study was undertaken to investigate the biologic function of NR2-reactive antibody in patients with SLE. The study included 14 patients with SLE, 9 of whom had NR2-reactive antibody. We analyzed the effects of NR2-reactive antibody on cell viability and intracellular Ca(2+)  level. We also investigated the efficacy of zinc as a modulator of the intracellular Ca(2+)  level in the presence of NR2-reactive antibody. There was a significant inverse correlation between the NR2-reactive antibody titer and cell viability (R(2)  = 0.67, P < 0.0001; n = 23), and there was a significant association between the NR2-reactive antibody titer and the intracellular Ca(2+)  level in NR1/NR2a-transfected HEK 293 cells (R(2)  = 0.69, P < 0.0001). Intracellular Ca(2+)  levels were significantly higher in cells incubated with IgG derived from NR2-reactive antibody-positive SLE patients than in those incubated with IgG derived from NR2-reactive antibody-negative SLE patients (P = 0.0002). The addition of zinc decreased the intracellular Ca(2+)  level in a dose-dependent manner. NR2-reactive antibody-positive SLE IgG weakened the efficacy of zinc as a negative modulator of the intracellular Ca(2+)  level.
assistant
Our findings indicate that NR2-reactive antibody decreases cell viability by Ca(2+)  influx in SLE through inhibition of the binding capacity of zinc. Final Decision: yes