Natural Killer Cells from Patients with Recombinase-Activating Gene and Non-Homologous End Joining Gene Defects Comprise a Higher Frequency of CD56bright NKG2A+++ Cells, and Yet Display Increased Degranulation and Higher Perforin Content.

Mutations of the recombinase Activating Genes 1 and 2 (RAG1, RAG2) in humans are associated with a broad range of phenotypes. For patients with severe clinical presentation, hematopoietic stem cell transplantation (HSCT) represents the only curative treatment, however high rates of graft failure and incomplete immune reconstitution have been observed, especially after unconditioned haploidentical transplantation. Studies in mice have shown that Rag-/- NK cells have a mature phenotype, reduced fitness and increased cytotoxicity. We aimed to analyze NK cell phenotype and function in patients with mutations in RAG and in non-homologous end joining (NHEJ) genes. Here we provide evidence that NK cells from these patients have an immature phenotype, with significant expansion of CD56bright CD16-/int CD57- cells, yet increased degranulation and high perforin content. Correlation was observed between in vitro recombinase activity of the mutant proteins, NK cell abnormalities, and in vivo clinical phenotype. Addition of serotherapy in the conditioning regimen, with the aim of depleting the autologous NK cell compartment, may be important to facilitate engraftment and immune reconstitution in patients with RAG and NHEJ defects treated by HSCT

Carriers of ADAMTS13 Rare Variants Are at High Risk of Life-Threatening COVID-19

Thrombosis of small and large vessels is reported as a key player in COVID-19 severity. However, host genetic determinants of this susceptibility are still unclear. Congenital Thrombotic Thrombocytopenic Purpura is a severe autosomal recessive disorder characterized by uncleaved ultra-large vWF and thrombotic microangiopathy, frequently triggered by infections. Carriers are reported to be asymptomatic. Exome analysis of about 3000 SARS-CoV-2 infected subjects of different severities, belonging to the GEN-COVID cohort, revealed the specific role of vWF cleaving enzyme ADAMTS13 (A disintegrin-like and metalloprotease with thrombospondin type 1 motif, 13). We report here that ultra-rare variants in a heterozygous state lead to a rare form of COVID-19 characterized by hyper-inflammation signs, which segregates in families as an autosomal dominant disorder conditioned by SARS-CoV-2 infection, sex, and age. This has clinical relevance due to the availability of drugs such as Caplacizumab, which inhibits vWF-platelet interaction, and Crizanlizumab, which, by inhibiting P-selectin binding to its ligands, prevents leukocyte recruitment and platelet aggregation at the site of vascular damage

Hematopoietic Stem Cell Transplantation in Primary Immunodeficiency Diseases: Current Status and Future Perspectives

Primary immunodeficiencies (PID) are disorders that for the most part result from mutations in genes involved in immune host defense and immunoregulation. These conditions are characterized by various combinations of recurrent infections, autoimmunity, lymphoproliferation, inflammatory manifestations, atopy, and malignancy. Most PID are due to genetic defects that are intrinsic to hematopoietic cells. Therefore, replacement of mutant cells by healthy donor hematopoietic stem cells (HSC) represents a rational therapeutic approach. Full or partial ablation of the recipient's marrow with chemotherapy is often used to allow stable engraftment of donor-derived HSCs, and serotherapy may be added to the conditioning regimen to reduce the risks of graft rejection and graft versus host disease (GVHD). Initially, hematopoietic stem cell transplantation (HSCT) was attempted in patients with severe combined immunodeficiency (SCID) as the only available curative treatment. It was a challenging procedure, associated with elevated rates of morbidity and mortality. Overtime, outcome of HSCT for PID has significantly improved due to availability of high-resolution HLA typing, increased use of alternative donors and new stem cell sources, development of less toxic, reduced-intensity conditioning (RIC) regimens, and cellular engineering techniques for graft manipulation. Early identification of infants affected by SCID, prior to infectious complication, through newborn screening (NBS) programs and prompt genetic diagnosis with Next Generation Sequencing (NGS) techniques, have also ameliorated the outcome of HSCT. In addition, HSCT has been applied to treat a broader range of PID, including disorders of immune dysregulation. Yet, the broad spectrum of clinical and immunological phenotypes associated with PID makes it difficult to define a universal transplant regimen. As such, integration of knowledge between immunologists and transplant specialists is necessary for the development of innovative transplant protocols and to monitor their results during follow-up. Despite the improved outcome observed after HSCT, patients with severe forms of PID still face significant challenges of short and long-term transplant-related complications. To address this issue, novel HSCT strategies are being implemented aiming to improve both survival and long-term quality of life. This article will discuss the current status and latest developments in HSCT for PID, and present data regarding approach and outcome of HSCT in recently described PID, including disorders associated with immune dysregulation

Reconstruction of post-traumatic losses of substance of the scalp Our experience

AIM: The reconstruction of post-traumatic losses of substance of the scalp is very difficult due to the unique characteristics of the scalp. The purpose of this paper is to evaluate the results obtained with several techniques in order to identify the most appropriate. METHODS: We treated 19 patients, 11 men and 8 women aged between 19 and 81 years, with post-traumatic loss of substance of the scalp from January 2006 to June 2011. The chosen treatments were the direct closure and the use of local flaps, the latter combined or not with the graft of the donor area and the post-operative correction of alopecic area with tissue expansion. RESULTS: None of the patients developed severe complications and all flaps were viable. The aesthetic results were variable, between good and satisfactory according to the technique used. CONCLUSION: The local flaps represent a good choice for the treatment of post-traumatic losses of substance of the scalp, restricting the use of direct suture and the use of skin grafting only in selected cases. Tissue expansion is a good choice for the revision of alopecic and cicatricial areas

Inborn Errors of Immunity With Immune Dysregulation: From Bench to Bedside

Inborn errors of immunity are genetic disorders with broad clinical manifestations, ranging from increased susceptibility to infections to significant immune dysregulation, often leading to multiple autoimmune phenomena, lymphoproliferation, and malignancy. The treatment is challenging as it requires careful balancing of immunosuppression in subjects at increased risk of infections. Recently, the improved ability to define inborn errors of immunity pathophysiology at the molecular level has set the basis for the development of targeted therapeutic interventions. Such a “precision medicine” approach is mainly bases on the use of available small molecules and biologics to target a specific cell function. In this article, we summarize the clinical and laboratory features of various recently described inborn errors of immunity associated with immune dysregulation and hyperinflammation in which mechanism-based therapeutic approaches have been implemented

A Novel 19F-NMR Method for the Investigation of the Antioxidant Capacity of Biomolecules and Biofluids

A new assay for the measurement of the antioxidant capacity of biomolecules by high resolution F-19-NMR spectroscopy is presented here. This method is based on the use of trifluoroacetanilidic detectors, namely trifluoroacetanilide, N-(4-hydroxyphenyl)-trifluoroacetamide and 2-hydroxy-4-trifluoroacetamidobenzoic acid. Upon hydroxyl radical attack, such fluorinated detectors yield trifluoroacetamide and trifluoroacetic acid that can be quantitatively determined by F-19-NMR spectroscopy. Trifluoroacetamide was found to be a reliable reporter of hydroxyl radical attack on the fluorinated detectors, whereas N-(4-hydroxyphenyl)-trifluoroacetamide was found to be the most sensitive detector amongst the ones considered. Therefore, N-(4-hydroxyphenyl)-trifluoroacetamide has been used in competition experiments to assess the antioxidant capacity of a number of low and high molecular weight antioxidants. The antioxidant capacity of a given compound has been scaled in terms of an adimensional parameter, k(F), that represents the ratio between the scavenger abilities of the fluorinated detector and the competitor. k(F) values obtained for low-molecular-mass compounds fall in the range 0.17 < k(F) < 1.5 and are in good agreement with second order rate constants (k(2)(OH)) for the reaction of the antioxidant with hydroxyl radicals. The k(F) value for serum albumin is much larger (46.9) than that predicted from the reported k(2)(OH) value. This finding supports the view that the protein can very effectively scavenge hydroxyl radicals as well as secondary radicals. Human blood serum showed that its antioxidant capacity is even higher than that shown by aqueous solutions of albumin at physiologic concentration suggesting a further contribution from other macromolecular serum components

Combination of tizanidine and amitriptyline in the prophylaxis of chronic tension–type headache: evaluation of efficacy and impact on quality of life

Chronic tension type headache (CTTH) has a strong impact on the Quality Of Life (QOL). We carried out an open–label randomized clinical trial on 18 patients with CTTH in order to compare two different regimens of pharmacological prophylaxis: the first provided for the use of amitriptyline 20 mg/d during 3 months, while in the second we combined amitriptyline with tizanidine (4 mg/d) in the first 3 weeks of treatment. Our hypothesis is that the combination therapy may guarantee an improvement of QOL even in the early stages of treatment. In fact, it's as well–known, there is a delay of 2–3 weeks in the prophylactic effect of amitriptyline, with a consequent persistence, in the first phases of therapy, of the headache and its negative impact. We assessed the following outcome measures: frequency, pain intensity, duration of headache and the Headache Impact Test (HIT) score, used as headache–related QOL measure. The combination therapy was effective since the first month of treatment, with a significant reduction of the headache, greater than one obtained with amitriptyline alone, in terms of frequency (–52,3% vs. –40,7%), intensity (–59,51% vs. –20,39%) and duration (–53,17% vs. –36,16%). This trend was confirmed by the HIT. Our data suggest that the combination of tizanidine with amitriptyline is faster than the amitriptyline alone in providing an improvement in the headache pattern and correlated QOL