Haploidentical stem cell transplantation in a boy with chronic granulomatous disease

Case report: HLA-haploidentical HSCT rescued with donor lymphocytes infusions in a patient with X-linked chronic granulomatous disease

Chronic granulomatous disease is an inborn error of immunity due to disrupted function of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex. This results in impaired respiratory burst of phagocytes and insufficient killing of bacteria and fungi. Patients with chronic granulomatous disease are at increased risk for infections, autoinflammation and autoimmunity. Allogeneic hematopoietic stem cell transplantation (HSCT) is the only widely available curative therapy. While HSCT from human leukocyte antigen (HLA) matched siblings or unrelated donors are standard of care, transplantation from HLA-haploidentical donors or gene therapy are considered alternative options. We describe a 14-month-old male with X-linked chronic granulomatous disease who underwent a paternal HLA-haploidentical HSCT using T-cell receptor (TCR) alpha/beta⁺/CD19⁺ depleted peripheral blood stem cells followed by mycophenolate graft versus host disease prophylaxis. Decreasing donor fraction of CD3⁺ T cells was overcome by repeated infusions of donor lymphocytes from the paternal HLA-haploidentical donor. The patient achieved normalized respiratory burst and full donor chimerism. He remained disease-free off any antibiotic prophylaxis for more than three years after HLA-haploidentical HSCT. In patients with x-linked chronic granulomatous disease without a matched donor paternal HLA-haploidentical HSCT is a treatment option worth to consider. Administration of donor lymphocytes can prevent imminent graft failure.

Failure to Prevent Severe Graft-Versus-Host Disease in Haploidentical Hematopoietic Cell Transplantation with Post-Transplant Cyclophosphamide in Chronic Granulomatous Disease

PURPOSE

Haploidentical related donor (HRD) transplantation was performed in 7 recipients with chronic granulomatous disease (CGD) who had no matched-related or unrelated donor.

METHODS

Peripheral blood cell (PBC) products were used with a conditioning regimen consisting of low-dose cyclophosphamide, fludarabine, total body irradiation, and busulfan. Graft-versus-host disease (GVHD) prophylaxis consisted of high-dose post-transplant cyclophosphamide and sirolimus. Recipients were ages 14-26 years, and 3 had severe infections active at transplant.

RESULTS

All 7 recipients achieved full engraftment with complete donor chimerism early in the post-transplant period. Acute GVHD occurred in all cases and was grade 3 or steroid refractory in 3. Two patients with steroid-refractory GVHD died. Three patients with severe infectious complications active at transplant, 1 Nocardia pneumonia and 2 extensive invasive fungal infections), survived and were cured of their infection at last follow-up. Bacterial disease occurred post-transplant in all recipients, and viral infections/reactivation were common, including 4 cases of BK virus-associated hemorrhagic cystitis.

CONCLUSIONS

Seven patients with CGD achieved rapid and full-donor engraftment from HRDs utilizing PBCs and a conditioning regimen with PTCy and sirolimus GVHD prophylaxis. However, the incidence of grade 3 and steroid-refractory GVHD was high and led to 2 deaths. Patients with active infections at transplant had successful transplant courses and were cured of their disease. Although there was an initial success with this regimen, the cumulative experience does not support its use in CGD due to an unacceptable rate of severe GVHD.

Cellular Therapies in Chronic Granulomatous Disease

Allogeneic hematopoietic stem cell transplantation (HSCT) has become the main curative treatment in patients with chronic granulomatous disease (CGD). CGD is caused by inherited defects of the phagolysomal NADPH-oxidase, leading to a lifelong propensity for invasive infections and granulomatous inflammation. After successful allogeneic HSCT, chronic infections and inflammation resolve and quality-of-life improves. Favorable long-term outcome after HSCT is dependent on the prevention of primary and secondary graft failure (GF), including falling myeloid donor chimerism (DC) below 10 %, and chronic graft-vs.-host-disease (cGVHD). The risk of GF and GvHD increases with the use of HLA-incompatible donors and this may outweigh the benefits of HSCT, mainly in patients with severe co-morbidities and in asymptomatic patients with residual NADPH-oxidase function. Seventeen scientific papers have reported on a total of 386 CGD-patients treated by HSCT with HLA-matched family/sibling (MFD/MSD), 9/10-/10/10-matched-unrelated volunteer (MUD) and cord blood donors. The median OS/EFS-rate of these 17 studies was 91 and 82%, respectively. The median rates of GF, cGVHD and de-novo autoimmune diseases were 14, 10, and 12%, respectively. Results after MFD/MSD and 10/10-MUD-transplants were rather similar, but outcome in adults with significant co-morbidities and after transplants with 9/10 HLA-MUD were less successful, mainly due to increased GF and chronic GVHD. Transplantation protocols using T-cell depleted haploidentical donors with post-transplant cyclophosphamide or TCR-alpha/beta depletion have recently reported promising results. Autologous gene-therapy after lentiviral transduction of HSC achieved OS/EFS-rates of 78/67%, respectively. Careful retrospective and prospective studies are mandatory to ascertain the most effective cellular therapies in patients with CGD.