Late Endocrine Effects after Stem Cell Transplant in a Young Girl with Griscelli Syndrome

Background. Griscelli syndrome (GS) is a rare disorder characterized by partial albinism and silver hair with alteration in genes necessary for melanin transport. Type 2 GS is fatal due to severe immunodeficiency without curative stem cell transplant (SCT). Late endocrinopathies are quite common in other disorders after SCT. These complications have not been reported in GS. Case Presentation. A 7-year-old female presented for growth failure with a history of GS status post curative SCT and consequently developed graft-versus-host disease (GvHD). She also had a history of eosinophilic enterocolitis, for which she was taking supraphysiologic glucocorticoids for the past year. She presented with severe short stature along with mild hyperthyroxinemia with subsequent diagnosis of Graves’ disease, which was treated with methimazole. GH therapy was commenced due to persistent growth failure, with a robust increase in growth parameters. She started spontaneous puberty; however, initial biochemical evaluation revealed hypergonadotropic hypogonadism with undetectable anti-Mullerian hormone (AMH) consistent with low ovarian reserve and premature ovarian failure. Discussion. Growth failure was multifactorial due to her inflammatory condition and poor weight gain from multiple underlying illnesses, including hyperthyroidism, as well as chronic supraphysiologic glucocorticoid use. Although hypothyroidism is more commonly seen after SCT, rare cases of hyperthyroidism have been reported. In addition to SCTs, GvHD and GS have been associated with autoimmune conditions. It is important to monitor pubertal progression as the majority of those treated with alkylating agents prior to SCT have pubertal and ovarian failure and remain at risk for premature menopause.

Successful rescue of a lethal Griscelli syndrome type 2 presenting with neurological involvement and hemophagocytic lymphohistiocytosis: a case report

Background Griscelli syndrome type 2 (GS2) is a rare autosomal recessive disease caused by mutations in RAB27A gene. It is primarily characterized by a combination of partial albinism, hemophagocytic lymphohistiocytosis (HLH) or other immunodeficiency. However, neurological involvement at onset in GS2 and treatment has rarely been described. Case presentation We describe a 3-year-old boy with GS2 in an Asian Chinese family. He presented with progressive neurological abnormalities following unremitting fever at onset. He developed HLH during the clinical course. A novel homozygous mutation (c.1 A > G) in RAB27A gene was subsequently identified. He was then treated by HLH-1994 protocol combined with ruxolitinib and experienced a dramatic remission. He subsequently underwent a successful haploidentical hematopoietic stem cell transplantation and stayed at a good condition. Conclusions We reported an atypical form of GS2 manifesting as severe central nervous system involvement at onset and subsequent HLH, which was successfully rescued in time. This case also highlights the need for early consideration of immunologic and genetic evaluation for HLH in unexplained neuroinflammation in the diagnostic work up.

Development, characterization, and hematopoietic differentiation of Griscelli syndrome type 2 induced pluripotent stem cells

Background Griscelli syndrome type 2 (GS-2) is a rare, autosomal recessive immune deficiency syndrome caused by a mutation in the RAB27A gene, which results in the absence of a protein involved in vesicle trafficking and consequent loss of function of in particular cytotoxic T and NK cells. Induced pluripotent stem cells (iPSC) express genes associated with pluripotency, have the capacity for infinite expansion, and can differentiate into cells from all three germ layers. They can be induced using integrative or non-integrative systems for transfer of the Oct4, Sox2, Klf4, and cMyc (OSKM) transcription factors. To better understand the pathophysiology of GS-2 and to test novel treatment options, there is a need for an in vitro model of GS-2. Methods Here, we generated iPSCs from 3 different GS-2 patients using lentiviral vectors. The iPSCs were characterized using flow cytometry and RT-PCR and tested for the expression of pluripotency markers. In vivo differentiation to cells from all three germlines was tested using a teratoma assay. In vitro differentiation of GS-2 iPSCs into hematopoietic stem and progenitor cells was done using Op9 feeder layers and specified media. Results All GS-2 iPSC clones displayed a normal karyotype (46XX or 46XY) and were shown to express the same RAB27A gene mutation that was present in the original somatic donor cells. GS-2 iPSCs expressed SSEA1, SSEA4, TRA-1-60, TRA-1-81, and OCT4 proteins, and SOX2, NANOG, and OCT4 expression were confirmed by RT-PCR. Differentiation capacity into cells from all three germ layers was confirmed using the teratoma assay. GS-2 iPSCs showed the capacity to differentiate into cells of the hematopoietic lineage. Conclusions Using the lentiviral transfer of OSKM, we were able to generate different iPSC clones from 3 GS-2 patients. These cells can be used in future studies for the development of novel treatment options and to study the pathophysiology of GS-2 disease.