Gene therapy. The legacy of Wacław Szybalski

Seminal demonstration of the possibility of stable genetic modification of mammalian cells performed by Wacław and Elisabeth Szybalski opened the doors for gene therapy, the term coined by Wacław Szybalski already in 1962. In the next 60 years, numerous tools for gene delivery have been developed and applied for clinical research, culminating in the registration of several genetic therapies in Europe and the USA. Some of these strategies, aimed to treat severe combined immunodeficiencies, inherited forms of blindness, spinal muscular atrophy, some cancers, and genetic anemias, are the real hope for patients suffering from previously incurable diseases or the ones whose treatment was not effective. On the approaching 60th anniversary of gene therapy, combined with the 100th anniversary of the birth of Professor Wacław Szybalski (September 9th, 1921), who passed away on December 16, 2020, here I present the summary of the most important aspects of clinical applications of genetic therapies.

Gene therapy for severe combined immunodeficiencies and beyond

Ex vivo retrovirally mediated gene therapy has been shown within the last 20 yr to correct the T cell immunodeficiency caused by γc-deficiency (SCID X1) and adenosine deaminase (ADA) deficiency. The rationale was brought up by the observation of the revertant of SCIDX1 and ADA deficiency as a kind of natural gene therapy. Nevertheless, the first attempts of gene therapy for SCID X1 were associated with insertional mutagenesis causing leukemia, because the viral enhancer induced transactivation of oncogenes. Removal of this element and use of a promoter instead led to safer but still efficacious gene therapy. It was observed that a fully diversified T cell repertoire could be generated by a limited set (<1,000) of progenitor cells. Further advances in gene transfer technology, including the use of lentiviral vectors, has led to success in the treatment of Wiskott–Aldrich syndrome, while further applications are pending. Genome editing of the mutated gene may be envisaged as an alternative strategy to treat SCID diseases.

A súlyos kombinált immundefektusok újszülöttkori szűrővizsgálata

Severe combined immunodeficiency is the first immune deficiency disorder which was included in the newborn screening program in the United States in 2010. In Hungary, newborn screening for severe combined immunodeficiencies is crucial because of the routine BCG vaccination, as in the case of an affected newborn with negative family history, the vaccine may lead to fatal BCG-itis. This paper analyzes the possibilities of introducing newborn screening for severe combined immunodeficiencies and summarizes current experiences and results. Orv Hetil. 2018; 159(23): 948–956.

Abstract 228: HYQVIA in Postural Orthostatic Tachycardia Syndrome(POTS)

Postural Orthostatic Tachycardia Syndrome (POTS) is a form of dysautonomia associated with variety of symptoms like Headache, Abdominal discomfort, Dizziness/presyncope, Nausea, Fatigue, Lightheadedness, Sweating Sleep disorder, Tremor, Anxiety, Palpitations, Exercise intolerance which is believed to be caused by an underlying infectious and/or autoimmune trigger. HYQVIA is an immune globulin with a recombinant human hyaluronidase indicated for the treatment of Primary Immunodeficiency (PI) in adults. This includes, but is not limited to, common variable immunodeficiency (CVID), X-linked agammaglobulinemia, congenital agammaglobulinemia, Wiskott-Aldrich syndrome, and severe combined immunodeficiencies. HYQVIA is a gammaglobulin and is a slow metabolizer given subcutaneously once a month.There is data that Intravenous immunoglobulin(IVIg) helps POTS patients. We present a case of 57 year old female diagnosed with autonomic failure,orthostatic intolerance and primary immune deficiency. She was given IVIg for primary immune deficiency. She was previously reported for severe autonomic failure. From then, she was doing extremely well, had more energy and she thinks more clearly. She also had much better attitude. She was getting albumin every 2 weeks or so for volume expansion. She felt IVIg had helped her. Her immunoglobulin was switched from Gammagard to HYQVIA 35 grams. After she did, her blood pressure had gone up. She took it with albumin and she felt palpitations and chest pain.She was stopped on albumin, as albumin and HYQVIA combined could cause more volume expansion and push her into fluid overload or even congestive heart failure. After she stopped albumin without HYQVIA, she did well. Similarly, she cut back on midodrine which is an α1 adrenergic agonist, and works by stimulating receptors that noradrenaline normally works on. After swallowing, midodrine is rapidly converted into another, more active drug that binds to noradrenaline receptors causing blood vessels to narrow, thereby increasing blood pressure andreduction in heart rate in POTS patients. She was only HYQVIA and had been feeling extremely well.

Early diagnostics of severe combined immunodeficiencies

Severe combined immunodeficiency is a big group of genetically determined immunological defects with a profound quantitative and/or functional deficiency of T- and B-cells, and sometimes NK-cells. The article contains our own experience of observation of patients with severe combined immunodeficiencies to establish early clinical and laboratory markers of SCID. A clinical, genealogical and laboratory analysis of 22 SCID patients and a comparison group was performed, the most common symptoms of this kind of PID and the time of their appearance were identified. It was found that the SCID patients do not have specific sings up to the manifestation of clinical symptoms of infections, and as early signs of the disease can be considered an eventful family history with children deaths at early age and lymphopenia below 3.0 х109 / l in 77,3 % of patients that can be used as screening laboratory finding in our country. An algorithm for diagnosis of SCID was proposed and the feasibility of practical implementation of neonatal screening for this disease was discussed.