Reviewed by Sarah Alter, Ph.D. — Scientific Affairs, OrganaBio. 15 years of immunology research spanning autoimmunity, cancer, and infectious disease. University of Miami Miller School of Medicine. Registered Patent Agent.
Multiple myeloma (MM) is a plasma cell malignancy characterized by clonal expansion of immunoglobulin-secreting plasma cells in the bone marrow. The treatment landscape has been transformed by CD38 targeting (daratumumab, isatuximab), BCMA-directed therapies (belantamab, ciltacabtagene autoleucel, idecabtagene vicleucel, teclistamab), and bispecific antibodies targeting BCMA, GPRC5D, and FcRH5. Peripheral blood PBMCs from MM donors are used to study ADCC mechanisms of CD38 and BCMA antibodies, characterize the immune suppression driving NK cell dysfunction, and assess T cell fitness for autologous CAR-T manufacturing in a disease where prior lines of therapy heavily alter the starting material.
MM Immune Biology and Therapeutic Context
MM cells express CD38 (high), BCMA (high), CD56, GPRC5D, and FcRH5 as therapeutic targets. NK cells are the primary ADCC effectors for daratumumab and isatuximab, but NK cells in MM are profoundly dysfunctional: CD38 is expressed on NK cells at levels that make daratumumab-induced NK cell fratricide a known pharmacological liability. CD38-mediated NK cell depletion is an active pharmacodynamic endpoint in anti-CD38 therapy studies, and anti-CD38 antibodies pre-treated with or without daratumumab show distinct NK cell killing profiles. BCMA CAR-T therapy is now standard in R/R MM, and T cell quality in heavily pre-treated MM donors is a critical determinant of manufacturing feasibility.
OrganaBio MM Donor Catalog
| Attribute | Available |
|---|---|
| Disease status | Active disease, VGPR/CR, relapsed/refractory documented |
| Treatment history | IMiD, proteasome inhibitor, anti-CD38 (daratumumab), BCMA-directed therapy |
| Prior CAR-T history | Documented on select lots; post-CAR-T T cell phenotype available |
| M-protein and SFLC | Available as disease activity markers on select lots |
| PBMC format | Cryopreserved; apheresis-derived |
| Lot documentation | CoA, disease status, treatment history, M-protein where available, flow cytometry |
Key Cell Populations for MM Research
- Circulating plasma cells / plasmablasts: CD38+/CD138+/CD56+; target cells for daratumumab and isatuximab ADCC assays; BCMA-expressing population for bispecific and CAR-T target validation
- NK cells (CD56+/CD16+): Primary ADCC effectors for anti-CD38; NK cell CD38 expression makes them targets of daratumumab fratricide; NK cell dysfunction in MM is profound and measurable in peripheral blood
- CD8+ T cells: Exhausted in MM; CAR-T manufacturing fitness (naive/memory ratios, PD-1 expression) critical for BCMA CAR-T programs
- CD4+ T cells: Tfh dysfunction in MM impairs anti-tumor immunity; daratumumab effects on CD4+ T cell cytokine production studied as secondary pharmacodynamics
- Regulatory T cells: Elevated frequency in MM; contribute to NK cell suppression and immune evasion
Research Applications
- Anti-CD38 (daratumumab, isatuximab) ADCC: NK cell-mediated killing of CD38+ MM cells with fratricide characterization
- BCMA bispecific antibody (teclistamab) and CAR-T (ciltacabtagene, idecabtagene) target validation: BCMA antigen density and expression on circulating MM plasma cells
- GPRC5D and FcRH5 bispecific target characterization: elranatamab and cevostamab target expression on MM PBMCs
- T cell fitness profiling for BCMA CAR-T manufacturing: naive/memory/exhaustion phenotype comparison by prior treatment lines
- IMiD (lenalidomide, pomalidomide) immune pharmacodynamics: NK cell and T cell activation in MM PBMCs
- Daratumumab NK cell fratricide quantification: CD38 expression on NK cells pre- and post-daratumumab treatment as mechanistic endpoint