A Novel Assay in Whole Blood Demonstrates Restoration of Mitochondrial Activity in Phagocytes After Successful HSCT in Hyperinflamed X-Linked Chronic Granulomatous Disease

Abstract

X-linked chronic granulomatous disease is a rare disease caused by mutations in the CYBB gene. While more extensive knowledge is available on genetics, pathogenesis, and possible therapeutic options, mitochondrial activity and its implications on patient monitoring are still not well-characterized. We have developed a novel protocol to study mitochondrial activity on whole blood of XCGD patients before and after transplantation, as well as on XCGD carriers. Here we present results of these analyses and of the restoration of mitochondrial activity in hyperinflamed X-linked Chronic Granulomatous Disease after hematopoietic stem cell transplantation. Moreover, we show a strong direct correlation between mitochondrial activity, chimerism, and DHR monitored before and after transplantation and in XCGD carriers. In conclusion, based on these findings, we suggest testing this new ready-to-use marker to better characterize patients before and after treatment and to investigate disease expression in carriers.

Keywords: Hematopoietic stem cell transplantation; Mitochondrial activity; Novel protocol on whole blood; Phagocytes disorders; Primary Immunodeficiency; X linked chronic granulomatous disease; X linked chronic granulomatous disease carriers; strong direct correlation between mitochondrial activity, hematopoietic stem cell transplantation chimerism and DHR monitored before and after transplantation and in XCGD carriers.

Fig. 1.

MitoSOX⁺ MFI (A) (E), percentage (B) (F) on granulocytes on whole blood and chest CT before (C) (G) and after HSCT (D) (H) in PT1 and in PT2 respectively

Fig. 2

MitoSOX⁺ MFI (A) and percentage (B) on granulocytes on whole blood; correlation of chimerism/ mitoSOX post HSCT (C), chimerism/DHR post HSCT (D), mitoSOX/DHR in carriers (E)

Fig. 3

Representative histograms for granulocyte mitoSOX+. In red before PMA stimulation, in blue after PMA stimulation. In PT1 basal (A), in PT1 at 1.5 years after HSCT (B), in a carrier (mother of PT2) (C), and in a healthy donor on the same day (D)

Fig. 4

A PT1 CT chest: vascularized pathological tissue infiltrating lung, pleura, chest wall (rib and dorsal vertebrae), esophageal fistula. B PT1 CT chest: clear reduction of pathological tissue devoid of vascularization with spinal stabilization. Partial resolution of esophageal fistula. C PT2 MRI dorso-lumbar spine: spondylodiscitis (vertebral edema and multiple paravertebral fluid collections). D PT2 MRI dorso-lumbar spine: complete resolution of vertebral edema and fluid paravertebral collections