Usefulness and Limitations of Rituximab in Managing Patients With Lymphoproliferative Disorder After Heart Transplantation

Synergistic anti-tumor therapy by a comb-like multifunctional antibody nanoarray with exceptionally potent activity

Simultaneously blocking multiple mediators offers new hope for the treatment of complex diseases. However, the curative potential of current combination therapy by chronological administration of separate monoclonal antibodies (mAbs) or multi-specific mAbs is still moderate due to inconvenient manipulation, low cooperative effectors, poor pharmacokinetics and insufficient tumor accumulation. Here, we describe a facile strategy that arms distinct mAbs with cooperative effectors onto a long chain to form a multicomponent comb-like nano mAb. Unlike dissociative parental mAbs, the multifunctional mAb nanoarray (PL-RB) constructed from type I/II anti-CD20 mAbs shows good pharmacokinetics. This PL-RB simultaneously targets distinct epitopes on a single antigen (Ag) and neighboring Ags on different lymphocytes. This unique intra- and intercellular Ag cross-linking endows the multifunctional mAb nanoarray with potent apoptosis activity. The exceptional apoptosis, complement-dependent cytotoxicity (CDC), antibody-dependent cellular cytotoxicity (ADCC) that are synchronously evoked by the nano PL-RB are further synergistically promoted via enhanced permeability and retention (EPR), which resulted in high intratumor accumulation and excellent anti-lymphoma efficiency.

Heterogeneity in clinical course of EBV-associated lymphoproliferative disorder after allogeneic stem cell transplantation

OBJECTIVE AND IMPORTANCE

Post-transplant lymphoproliferative disorder (PTLD) is a severe complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT) associated with Epstein-Barr virus (EBV).

CLINICAL PRESENTATIONS

Among 263 individuals treated with allo-HSCT for severe aplastic anemia, pure white cell aplasia, T-prolymphocytic leukemia, and relapsed Hodgkin lymphoma, we diagnosed EBV-PTLD in 5 patients. Median age was 29 years (range 19-70 years) and four of five patients were EBV-seropositive prior to HSCT. All five had unrelated EBV-positive donors. In all cases, PTLD occurred within the first year post-transplant (median 4 months).

INTERVENTION

There were two rapidly fatal courses with extensive organ involvement. Both patients showed lymphopenia and thrombocytopenia. In contrast, the three surviving patients had higher lymphocytes and normal platelet counts, while PTLD was restricted to one site and resolved after 2-4 cycles of rituximab.

CONCLUSION

In this case series courses of PTLD showed substantial diversity.