Polymorphism of the HLA system and weak antibody response to BNT162b2 mRNA vaccine.

The polymorphism of the HLA system has been extensively studied in COVID-19 infection, however there are no data about the role of HLA on vaccine response. We report here the HLA-A, -B, -C, and DRB1 allelic frequencies of n = 111 individuals after BNT162b2 mRNA vaccine, selected on the basis of lower antibody levels (<5% percentile) after the second dose among a total of n = 2569 vaccinees, and compare them with the frequencies of a reference population. We found that differences in the frequencies of the alleles HLA-A*03:01, A*33:03, B*58:01 and at least one haplotype (HLA-A*24:02~C*07:01~B*18:01~DRB1*11:04) are associated with a weaker antibody response after vaccination, together with the age of vaccinees.

Use of DPB1 T-cell epitope algorithm among italian transplant centers: A survey on behalf of Associazione Italiana di Immunogenetica e Biologia dei Trapianti.

The HLA-DPB1 locus has been demonstrated to have a significant role on patients' outcome after allogeneic HSCT, and the so-called T-cell epitope (TCE) algorithm has been incorporated in international guidelines for the selection of unrelated donors. The purpose of the present study is to measure, through a national survey conducted on behalf of the Associazione Italiana di Immunogenetica e Biologia dei Trapianti (AIBT), the extent of awareness and use of HLA-DPB1 TCE-based algorithms during the donor search. 89% of the HLA laboratories answered to a short questionnaire and the results showed a progressive increase of the laboratories typing DPB1 in patients and their potential donors during the search (from 44% to 79% during the 2010-2019 period) as well as the application of a TCE-based algorithm for the donor choice whenever possible (from 24% to 65% during the same period).

Allelic HLA Matching and Pair Origin Are Favorable Prognostic Factors for Unrelated Hematopoietic Stem Cell Transplantation in Neoplastic Hematologic Diseases: An Italian Analysis by the Gruppo Italiano Trapianto di Cellule Staminali e Terapie Cellulari, Italian Bone Marrow Donor Registry, and Associazione Italiana di Immunogenetica e Biologia dei Trapianti.

HLA molecules are important for immunoreactivity in allogeneic hematopoietic stem cell transplantation (HSCT). The Gruppo Italiano Trapianto di Cellule Staminali e Terapie Cellulari, Italian Bone Marrow Donor Registry, and Associazione Italiana di Immunogenetica e Biologia dei Trapianti promoted a retrospective observational study to evaluate HLA matching and the impact of allelic HLA mismatching and non-HLA factors on unrelated Italian HSCT outcomes. From 2012 to 2015, 1788 patients were enrolled in the study.

HLA and immunological features of SARS-CoV-2-induced Guillain-Barré syndrome.

We report the clinical and immunological features in a case of SARS-CoV-2-induced Guillain-Barré syndrome (Si-GBS), suggesting that (1) Si-GBS can develop even after paucisymptomatic COVID-19 infection; (2) a distinctive cytokine repertoire is associated with this autoimmune complication, with increased CSF concentration of IL-8, and moderately increased serum levels of IL-6, IL-8, and TNF-α; (3) a particular genetic predisposition can be relevant, since the patient carried several HLA alleles known to be associated with GBS, including distinctive class I (HLA-A33) and class II alleles (DRB1*03:01 and DQB1*05:01). To the best of our knowledge, this is the first case of GBS in which SARS-CoV-2 antibodies were detected in the CSF, further strengthening the role of the virus as a trigger. In conclusion, our study suggests that SARS-CoV-2 antibodies need to be searched in the serum and CSF in patients with GBS living in endemic areas, even in the absence of a clinically severe COVID-19 infection, and that IL-8 pathway can be relevant in Si-GBS pathogenesis.

A new HLA-B allele, HLA-B*35:481.

The novel allele HLA-B*35:481 differs from HLA-B*35:05:01 by two nucleotide substitution in exon 3.

Molecular RH blood group typing of serologically D-/CE+ donors: the use of a polymerase chain reaction-sequence-specific primer test kit with pooled samples.

The known presence of RHD blood group alleles in apparently D– individuals who are positive for C or E antigens leads to an appropriate investigation for the RHD gene on the red blood cells (RBCs) of D– blood donors, thus preventing their RBCs from immunizing D– recipients. Ready-to-use polymerase chain reaction–sequence-specific primer (PCR-SSP) typing kits are available and allow single-sample results. The need to perform this testing on a large number of donors affiliated with the Transfusion Department of Udine (Northern Italy) led to the use of molecular genetic RH blood group typing with PCR-SSP test kits and DNA samples mixed in pools.

HLA-DQ types of celiac disease in Libyan children with type 1 diabetes mellitus.

Objective: To determine the genetic profile of celiac disease (CD) in Libyan children with type 1 diabetes as there are no data on the frequency of human leukocyte antigen (HLA)-related CD-predisposing genes in diabetic patients in Libya.

Methods: We randomly studied 218 Libyan type 1 diabetic children. The mean age was 12.

Autoimmune thyroid disease in Libyan children and young adults with type 1 diabetes mellitus.

Unlabelled: Diabetes mellitus is a common autoimmune endocrine disorder associated with organ-specific autoantibodies which are frequently detected at the time of diagnosis. Some of these antibodies are specific to the pancreas (GAD, IA2, ICA) while others are related to different autoimmune diseases.

Aim Of The Study: To define the prevalence of thyroid autoimmune disease in Libyan patients with type 1 diabetes mellitus (T1DM) since no similar studies have been performed in Libya.

Nonpermissive HLA-DPB1 disparity is a significant independent risk factor for mortality after unrelated hematopoietic stem cell transplantation.

The importance of donor-recipient human leukocyte antigen (HLA)-DPB1 matching for the clinical outcome of unrelated hematopoietic stem cell transplantation (HSCT) is controversial. We have previously described an algorithm for nonpermissive HLA-DPB1 disparities involving HLA-DPB1*0901,*1001,*1701,*0301,*1401,*4501, based on T-cell alloreactivity patterns. By revisiting the immunogenicity of HLA-DPB1*02, a modified algorithm was developed and retrospectively tested in 621 unrelated HSCTs facilitated through the Italian Registry for oncohematologic adult patients.

Frequency of the HFE gene mutations in five Italian populations.

Genetic hemochromatosis is an autosomal recessive disorder characterized by iron overload and a variety of clinical manifestations such as liver cirrhosis and arthropathy. It is the most common genetic disease of northern European populations. The principal gene responsible for hereditary hemochromatosis, designated HFE, is located on chromosome 6 in the HLA region.