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Резюме. Первичные иммунодефициты (ПИД), тяжелый комбинированный иммунодефицит (ТКИН) и Х-сцепленная агаммаглобулинемия, характеризуются отсутствием функциональных Ти В-лимфоцитов соответственно. Без своевременной ранней диагностики и лечения дети с ПИД страдают от инфекционных заболеваний с тяжелым течением, что приводит к их инвалидизации или смерти. Цель: разработать и апробировать на группе детей с верифицированными диагнозами ТКИН и Х-сцепленной агаммаглобулинемией простую, недорогую, высокопропускную методику на основе количественного определения молекул ДНК TREC и KREC с помощью ПЦР в режиме реального времени. В настоящем исследовании мы разработали и валидировали метод проведения мультиплексной полимеразной цепной реакции в режиме «реального времени» для количественного анализа молекул ДНК TREC и KREC. Нами было показано, что в области концентраций от 10 9 коп/мл до 5 × 10 4 коп/ мл для всех мишеней наблюдается линейный диапазон изменения Сt в зависимости от концентрации с коэффициентом корреляции R 2 не хуже 0,98. Наименьшее количество копий, надежно детектиру-Gordukova M.A. et al. Гордукова М.А. и др. Medical Immunology (Russia)/Meditsinskaya Immunologiya Медицинская Иммунология емых в одной ПЦР реакции объемом 25 мкл, было: 10 для TREC, 5 для KREC и 5 для внутреннего контроля-локуса IL17RA. Нами определены референсные значения для количества TREC и KREC в цельной крови в зависимости от возраста в группе из 29 мальчиков и 27 девочек с нормальными иммунологическими параметрами. Были определены граничные значения для содержания TREC и KREC в сухих пятнах крови в зависимости от метода экстракции ДНК. Предложенная методика показала 100% диагностическую чувствительность и специфичность на исследуемой выборке. Метод может быть предложен как скрининговый для диагностики ТКИН и Х-сцепленной агаммаглобулинемии как в цельной крови, так и в сухих пятнах крови. Требуется дальнейшая апробация методики на выборках большего объема.

Primary immunodeficiency diseases (PID) is a heterogeneous group of disorders caused by genetic defects of the immune system, which manifests clinically as recurrent infections, autoimmune diseases, or malignancies. Early detection of other PID remains a challenge, particularly in older children due to milder and less specific symptoms, a low level of clinician PID awareness and poor provision of hospital laboratories with appropriate devices. T-cell recombination excision circles (TREC) and kappa-deleting element recombination circle (KREC) in a dried blood spot and in peripheral blood using real-time polymerase chain reaction (PCR) are used as a tool for severe combined immune deficiency but not in PID. They represent an attractive and cheap target for a more extensive use in clinical practice. This study aimed to assess TREC/KREC correspondence with lymphocyte subpopulations, measured by flow cytometry and evaluate correlations between TREC/KREC, lymphocyte subpopulations and immunoglobulins. We carried out analysis of data from children assessed by clinical immunologists at Speransky Children’s Hospital, Moscow, Russia with suspected immunodeficiencies between May 2013 and August 2016. Peripheral blood samples were sent for TREC/KREC, flow cytometry (CD3, CD4, CD8, and CD19), IgA, IgM, and IgG analysis. A total of 839 samples were analyzed for using TREC assay and flow cytometry and 931 KREC/flow cytometry. TREC demonstrated an AUC of 0.73 (95% CI 0.70–0.76) for CD3, 0.74 (95% CI 0.71–0.77) for CD4 and 0.67 (95% CI 0.63–0.70) for CD8, respectively, while KREC demonstrated an AUC of 0.72 (95% CI 0.69–0.76) for CD19. Moderate correlation was found between the levels of TREC and CD4 (r = 0.55, p < 0.01) and KREC with CD19 (r = 0.56, p < 0.01). In this study, promising prediction models were tested. We found that TREC and KREC are able to moderately detect abnormal levels of individual lymphocyte subpopulations. Future research should assess associations between TREC/KREC and other lymphocyte subpopulations and approach TREC/KREC use in PID diagnosis.

Objectives: Mutations in the neuroblastoma-amplified sequence (NBAS) gene were originally described in patients with skeletal dysplasia or isolated liver disease of variable severity. Subsequent publications reported a more complex phenotype. Among multisystemic clinical symptoms, we were particularly interested in the immunological consequences of the NBAS deficiency. Methods: Clinical and laboratory data of 3 patients ages 13, 6, and 5 in whom bi-allelic NBAS mutations had been detected via next-generation sequencing were characterized. Literature review of 23 publications describing 74 patients was performed. Results: We report three Russian patients with compound heterozygous mutations of the NBAS gene who had combined immunodeficiency characterized by hypogammaglobulinemia, low T-cells, and near-absent B-cells, along with liver disease, skeletal dysplasia, optic-nerve atrophy, and dysmorphic features. Analysis of the data of 74 previously reported patients who carried various NBAS mutations demonstrated that although the most severe form of liver disease seems to require disruption of the N-terminal or middle part of NBAS, mutations of variable localizations in the gene have been associated with some form of liver disease, as well as immunological disorders. Conclusions: NBAS deficiency has a broad phenotype, and referral to an immunologist should be made in order to screen for immunodeficiency.

BackgroundMevalonate kinase deficiency (MKD) is a rare autosomal recessive autoinflammatory disease caused by mutations in MVK gene. MKD patients typically have an early onset of symptoms including recurrent episodes of high fever, abdominal pain, diarrhea and vomiting, arthralgia and lymphadenopathy. However not all patients have typical clinical picture of MKD.MethodsWe conducted a retrospective analysis of clinical features of six patients (4 females, 2 males) with MKD (confirmed by identification of MVK gene mutations). Four patients received therapy with inhibitors of IL-1 (Anakinra and/or Canakinumab). One of the patients died from amyloidosis and macrophage activation syndrome (MAS) prior to treatment initiation, her diagnosis was verified post mortem.ResultsAll patients had the first symptoms of disease within the first 6 months of life. During the course of the disease all patients had periodic fever and peripheral lymphadenopathy (mainly cervical group), as well as abdominal pain, nausea/vomiting. Five patients had diarrhea, sometimes with blood, one patient suffered from severe constipation. Rash was seen in five patients, myalgia, artralgia were observed only in four. Oral ulcers were noted in two children. Two patients had neurological involvement. Interestingly, five out of six patients had rhinitis during attacks. One patient during the attack had periorbital edema and hyperemia, which; to our knowledge, have not been reported previously in MKD. One patient developed amyloidosis and MAS before treatment initiation, which led to her death. In patients receiving anti-IL-1 therapy AIDAI index decreased from 49.5±14,6 before to 1,75±1,3 after 6 month of therapy (p=0.003).ConclusionsMKD symptoms can be variable and sometimes atypical, which requires physician's awareness. In our small cohort of MKD patients anti IL-1 therapy was highly effective.Disclosure of InterestNone declared