DEFECTIVE CD36 MUTATIONS IN ANTI-Naka ANTIBODY-POSITIVE SUBJECTS ASSOCIATED WITH TRANSFUSION-RELATED ACUTE LUNG INJURY (TRALI)

Mechanism and intervention of murine transfusion-related acute lung injury caused by anti-CD36 antibodies

Anti-CD36 Abs have been suggested to induce transfusion-related acute lung injury (TRALI) upon blood transfusion, particularly in Asian populations. However, little is known about the pathological mechanism of anti-CD36 Ab-mediated TRALI, and potential therapies have not yet been identified. Here, we developed a murine model of anti-CD36 Ab-mediated TRALI to address these questions. Administration of mouse mAb against CD36 (mAb GZ1) or human anti-CD36 IgG, but not GZ1 F(ab')2 fragments, induced severe TRALI in Cd36+/+ male mice. Predepletion of recipient monocytes or complement, but not neutrophils or platelets, prevented the development of murine TRALI. Moreover, plasma C5a levels after TRALI induction by anti-CD36 Abs increased more than 3-fold, implying a critical role of complement C5 activation in the mechanism of Fc-dependent anti-CD36-mediated TRALI. Administration of GZ1 F(ab')2, antioxidant (N-acetyl cysteine, NAC), or C5 blocker (mAb BB5.1) before TRALI induction completely protected mice from anti-CD36-mediated TRALI. Although no significant amelioration in TRALI was observed when mice were injected with GZ1 F(ab')2 after TRALI induction, significant improvement was achieved when mice were treated postinduction with NAC or anti-C5. Importantly, anti-C5 treatment completely rescued mice from TRALI, suggesting the potential role of existing anti-C5 drugs in the treatment of patients with TRALI caused by anti-CD36.

A case of Philadelphia chromosome-positive acute lymphocytic leukaemia with type I CD36 deficiency

BACKGROUND

CD36 is a glycoprotein expressed on platelets and monocytes of the blood. There are two types of CD36 deficiency, type I and type II. Individuals with type I-deficiency do not express CD36 in any cell type and can produce the CD36 antibody, which causes pathological conditions, such as fetal/neonatal alloimmune thrombocytopenia (FNAIT) and platelet transfusion refractory (PTR), through antigenic exposure via transfusion or pregnancy.

CASE PRESENTATION

We experienced a case of Philadelphia-positive acute lymphoblastic leukaemia with PTR. In addition to the CD36 antibody, multiple-specificity HLA antibodies were present in the patient's plasma, requiring transfusion of HLA-compatible and CD36-negative platelets (PC-HLA). Since the number of donors was limited, it was necessary to set-up a blood transfusion schedule so that hyper-fractionated cyclophosphamide, vincristine and doxorubicin therapy (hyper-CVAD) and ponatinib combination chemotherapy could be safely administered to achieve molecular remission. Rituximab administration resulted in reduced levels of both CD36 antibody and HLA antibody. Given the expression of CD36 on haematopoietic stem cells and the limited availability of CD36-negative PC-HLA, haematopoietic stem cell transplantation (HSCT) was not considered to be an option.

CONCLUSION

If CD36-negative, allogeneic haematopoietic stem cell donors are unable to be found, the indications for HSCT in patients with type I CD36-deficiency should be carefully weighed. In the present case, molecular remission has been able to be maintained to the present day after completion of a two-year maintenance regimen.