Cd19 b cells

Purified PBMCs, naïve CD4⁺ T cells, and CD19⁺ B cells (isolated by positive selection) from healthy donors were purchased from AllCells. Matched (age, gender, race, Table S1) SLE patient and healthy donor PBMCs were acquired from Conversant (Now Discovery Life Sciences). KZR-616 stock was dissolved in DMSO; DMSO was used as vehicle control for in vitro and ex vivo studies.

CD4+ T cells, CD19+ B cells and neutrophils from venous blood of a healthy Caucasian male donor were purchased from AllCells Company (AllCells, Alameda, California). The use of the cells for research purpose has AllCells company IRB approval (Biomed IRB). The donor signed the written consent form, which is archived with their medical records. All experiments were performed in accordance with relevant guidelines and regulations. According to US Federal Regulations, 45 CFR Part 46.101(b)(4)–Protection of Human Subjects, using this type of human cells for research is exempted from the requirement for IRB review.