ABSTRACT
Hematopoietic stem-cell gene therapy is a promising treatment of X-linked severe combined immunodeficiency disease (SCID-X1), but currently, it requires recipient conditioning, extensive cell manipulation, and sophisticated facilities. With these limitations in mind, we explored a simpler therapeutic approach to SCID-X1 treatment by direct IV administration of foamy virus (FV) vectors in the canine model. FV vectors were used because they have a favorable integration site profile and are resistant to serum inactivation. Here, we show improved efficacy of our in vivo gene therapy platform by mobilization with granulocyte colony-stimulating factor (G-CSF) and AMD3100 before injection of an optimized FV vector incorporating the human phosphoglycerate kinase enhancerless promoter. G-CSF/AMD3100 mobilization before FV vector delivery accelerated kinetics of CD3+ lymphocyte recovery, promoted thymopoiesis, and increased immune clonal diversity. Gene-corrected T lymphocytes exhibited a normal CD4:CD8 ratio and a broad T-cell receptor repertoire and showed restored γC-dependent signaling function. Treated animals showed normal primary and secondary antibody responses to bacteriophage immunization and evidence for immunoglobulin class switching. These results demonstrate safety and efficacy of an accessible, portable, and translatable platform with no conditioning regimen for the treatment of SCID-X1 and other genetic diseases.
Subject(s)
Dog Diseases , Genetic Therapy , Genetic Vectors/pharmacology , Granulocyte Colony-Stimulating Factor/pharmacology , Hematopoietic Stem Cell Mobilization , Heterocyclic Compounds/pharmacology , Spumavirus , X-Linked Combined Immunodeficiency Diseases , Animals , Benzylamines , CD4-CD8 Ratio , Cyclams , Disease Models, Animal , Dog Diseases/blood , Dog Diseases/genetics , Dog Diseases/therapy , Dogs , Humans , Phosphoglycerate Kinase/genetics , X-Linked Combined Immunodeficiency Diseases/blood , X-Linked Combined Immunodeficiency Diseases/genetics , X-Linked Combined Immunodeficiency Diseases/therapy , X-Linked Combined Immunodeficiency Diseases/veterinarySubject(s)
Interleukin Receptor Common gamma Subunit/genetics , Killer Cells, Natural/immunology , Mutation , X-Linked Combined Immunodeficiency Diseases/genetics , X-Linked Combined Immunodeficiency Diseases/immunology , Female , Humans , Infant , Male , Pedigree , Phenotype , X-Linked Combined Immunodeficiency Diseases/bloodSubject(s)
Immunoglobulins/therapeutic use , Immunologic Deficiency Syndromes/drug therapy , Infusions, Subcutaneous , X-Linked Combined Immunodeficiency Diseases/drug therapy , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal, Murine-Derived , Child, Preschool , Disease-Free Survival , Female , Humans , Immunoglobulins/blood , Immunoglobulins/deficiency , Immunoglobulins, Intravenous/therapeutic use , Immunologic Deficiency Syndromes/blood , Immunologic Deficiency Syndromes/chemically induced , Immunologic Deficiency Syndromes/diagnosis , Immunologic Deficiency Syndromes/genetics , Immunologic Deficiency Syndromes/physiopathology , Infant , Infections , Lymphopenia , Male , Rituximab , X-Linked Combined Immunodeficiency Diseases/blood , X-Linked Combined Immunodeficiency Diseases/diagnosis , X-Linked Combined Immunodeficiency Diseases/genetics , X-Linked Combined Immunodeficiency Diseases/physiopathologyABSTRACT
In this report, we describe a patient with X-linked severe combined immunodeficiency (X-SCID) who had high serum IgG, IgA, and IgM levels. The boy did well until 6 months of age, when he developed interstitial pneumonia caused by Aspergillus species, with a white cell count of 12,840/microL and only 10% lymphocytes; IgG, 991 mg/dL; IgA, 65 mg/dL; IgM, 472 mg/dL. Cell markers showed only 6.3% CD3, 2.1% CD4, 0.7% CD8, but 92% CD19 and 0.1% CD16+CD56+ (NK cells). A mutation was detected within exon 2 (C196 A-->C), leading to the substitution of proline for glutamine, which has not been reported previously. The boy was successfully treated with the new antifungal drug, micafangin (MCFG), at 5 mg/kg/day for 89 days. After resolution of the pneumonia, the patient underwent successful hematopoietic stem cell transplantation with completely matched unrelated female cord blood. The CD34 stem cell dose was 3.4 x 10(4) cells/kg. In conclusion, MCFG can be a first line agent for Aspergillus pneumonia in immunocompromised hosts.
