Single-cell RNA Sequencing (scRNA-seq) to Investigate the Mechanisms Underlying the Induction of Regulatory T Cells in Patients With Extramembranous Glomerulonephritis Treated With Rituximab

Condition(s) studied

Investigational drug(s) / intervention(s)

Peripheral blood immune-cell profiling by single-cell RNA sequencing and in vitro pathway modulation assays: Participants with active anti-PLA2R1-positive membranous nephropathy and a routine-care indication for rituximab will undergo two additional research blood collections: one at Day 0 before or on the day of the first rituximab infusion, and one at Month 6. Peripheral blood mononuclear cells will be isolated, cryopreserved, and analyzed by single-cell RNA sequencing. Candidate signaling pathways associated with regulatory T-cell induction will be assessed in vitro using pathway activators or inhibitors and flow cytometry-based Treg measurement. Rituximab itself is administered as part of usual care at 1 g on Day 0 and 1 g on Day 15, not as an investigational treatment assigned by the study.

Study summary

Membranous nephropathy is a rare autoimmune kidney disease in which autoantibodies, most commonly anti-PLA2R1 antibodies, target podocyte antigens and may cause nephrotic syndrome. Rituximab is used in routine care to deplete B cells and reduce pathogenic autoantibodies, but its effects are not limited to B-cell depletion. Previous work suggests that rituximab may also promote regulatory T-cell (Treg) responses, and higher Treg levels after treatment have been associated with clinical remission.

TRANSCRIPT is a prospective, single-center, pilot mechanistic study in 12 adult patients with active anti-PLA2R1-positive membranous nephropathy who have an indication for rituximab as part of routine care. Participants will receive rituximab according to usual clinical practice (1 g on Day 0 and 1 g on Day 15). Additional blood samples will be collected at Day 0 and Month 6 to isolate peripheral immune cells. Single-cell RNA sequencing will be used to identify transcriptional changes, signaling pathways, and intercellular communication networks associated with rituximab-induced Treg induction. In vitro assays will then test modulators of the candidate pathways identified by sequencing.

The study hypothesis is that rituximab modulates immune-cell signaling and communication pathways that contribute to the induction of regulatory T cells in patients with membranous nephropathy.

Eligibility

Primary outcome measure(s)

• Change in regulatory T-cell induction and rituximab-modulated immune signaling pathways from Day 0 to Month 6 — Day 0 to Month 6
  Regulatory T-cell induction will be assessed by single-cell RNA sequencing of peripheral immune cells collected from 12 rituximab-treated participants at Day 0 and Month 6. The analysis will identify differentially expressed genes and their fold changes within immune-cell subpopulations, including Treg cells and partner immune-cell populations. It will also identify the main signaling and cell-cell communication pathways that are deregulated or modulated between Day 0 and Month 6.

Trial sites (1)

More Centre Hospitalier Universitaire de Nice trials in France

Other trials for the same condition