Role of cytokine and Toll-like receptor genes in pathogenesis of inborn heart disease

Sporadic congenital heart disease (CHD) may result from immune disorders in the mother – embryo system and/or constitutional disorders in regulatory systems, including those associated with TLR receptors, cytokines and their receptors. The aim of our study was to investigate associations between cytokine and TLR genes and sporadic congenital heart disease in children. In the main group, 188 children with sporadic (without family history) congenital heart defects were examined. Separate groups of CHD were identified: septal CHD – 98 children; valvular heart disease – 17 children; Fallot tetralogy – 15 children; aorta coarctation – 10 children; fetal drains – 32 children; single ventricle affection – 9 children, and anomalous drainage of v. pulmonalis was diagnosed in 7 children. The control group included 103 age- and sex-matched healthy children. We have determined gene polymorphisms of five genes encoding cytokines and their receptors (IL6 rs1800796, IL6 rs2069827, IL6R rs2228145, IL6R rs2229238, IL8 rs4073, IL10 rs1800871, IL10 rs1800896, IL10 rs1800872, TNF rs1800629, TNF rs361525, TNF rs1799964), four genes Toll-like receptors (TLR: TLR1 rs5743611, TLR1 rs5743551, TLR2 rs5743708, TLR2 rs3804099, TLR4 rs4986791, TLR4 rs4986790, TLR6 rs3775073, TLR6 rs5743810). The dbSNP, SNPinfo, SNPnexus databases were used to select and design test systems. Stepwise logistic regression was the main method of statistical analysis. Clinical diagnosis of congenital heart defects is associated with immune regulatory genes. In particular, the missense mutation TLR6 rs5743810, which was a predictor of congenital valvular heart disease, is of particular importance. Development of congenital heart valve defects and aortic coarctation is associated with intergenic interactions of TLR2 rs5743708 with TLR6 rs5743810, and TLR2 rs5743708 with TLR6 rs3775073, respectively. For congenital heart valve defects, such polymorphic regions are as follows: IL6 rs2069827, IL6R rs2229238, and IL8 rs4073, for aortic coarctation – IL6R rs2228145, IL8 rs4073. Development of septal congenital heart defects is associated with general contribution of polymorphic variants of the TLR genes and cytokines to this pathology. A missense mutation of the TLR4 rs4986790 gene and a TNF rs1799964 mutation leading to increased synthesis of the TNFα molecule, may have a combined effect on this process. In general, contribution of TLR and cytokine genes interactions to the CHD development seems to be not significant

FREQUENCY DISTRIBUTION OF INTRONIC POLYMORPHISMS OF IL1-raVNTR AND IL-4VNTR IN RHEUMATIC MITRAL VALVE DISEASE IN CAUCASIAN POPULATION OF SIBERIA

A search for associations between allelic variations of immune response genes, and mitral stenosis associated with rheumatic heart disease, represents an important task when studying the pathogenesis of cardiovascular disorders among inhabitants of large industrial regions in Western Siberia. Among multiple polymorphisms of interleukin-encoding genes, a particular attention should be paid to association studies of some intronic polymorphisms with variable numbers of tandem repeats (VNTR). In this respect, genotyping of interleukin 1 receptor antagonist genes (IL-1ra86bp VNTR) and interleukin 4 (IL-470bp VNTR) has shown positive associations between the intron 2 IL-1ra*3R/3R microsatellite polymorphism, intron 3 IL-4*2R/2R variant, and the risk of mitral stenosis development in patients with rheumatic heart disease (OR = 12.71; p = 0.0001)

Association of polymorphisms the trigger receptor gene expressed by myeloid cells (<i>TREM-1</i>) in sporadic congenital heart defects without chromosome anomalies

Eight polymorphic loci in the TREM-1 gene (rs1817537, rs3804277, rs6910730, rs7768162, rs2234246, rs4711668, rs9471535 and rs2234237) were genotyped in 131 children with congenital heart defects (CHD) without proven chromosomal anomalies, and 103 conditionally healthy children (control group) matched for age and gender. Genotyping was performed by polymerase chain reaction (PCR) using TaqMan probes. The frequency of these genotypes was checked for Hardy–Weinberg equilibrium using a free tool (http://bioinfo.iconcologia.net/SNPstats). Analysis of inter-locus interactions was performed by Multifactor Dimensionality Reduction method. It was shown that the combination of four loci, i.e., rs1817537, rs3804277, rs2234246 and rs7768162 may determine susceptibility and persistence for CHD without chromosomal diseases. Increased CHD risk is associated with two-locus model rs1817537*G/G – rs3804277*T/T (OR = 8.26) and three-locus model rs2234246*C/T – rs1817537*C/G – rs7768162*A/G (OR = 13.76). The two-locus model rs1817537*С/С – rs3804277*T/T (OR = 0.03) and three-locus model rs2234246*T/T – rs1817537*C/C – rs7768162*G/G (OR = 0.03) were associated with a decreased risk for CHD without detectable chromosomal anomalies

Changes in the expression of HLA-DR on lymphocyte subpopulations of spouses having children with sporadic congenital heart defects without chromosomal diseases, under the influence of female’s autoserum

This study is aimed to investigate the effect of female autoserum on the HLA-DR expression in various subpopulations of lymphocytes obtained from spouses with children with sporadic congenital heart defects without chromosomal diseases. 78 married couples with children with congenital heart disease were included in the study group. The control group was formed from 35 married couples with healthy children. The immune response in a mixed culture of lymphocytes of spouses was evaluated by an increased HLA-DR expression in a mixed culture in relation to spontaneous cultures of lymphocytes. Primary staining of female and male lymphocytes by monoclonal antibodies to CD45 conjugated with various fluorescent dyes (PC-5 and PC-7) was performed to assess the immune response of female lymphocytes to male ones and vice versa. The activating effect of female autoserum on all subpopulations of female lymphocytes simultaneously occurred significantly less frequently in the study group compared to the control. The control group was characterized by the domination of the positive effect of female autoserum on HLA-DR expression for all subpopulations of female lymphocyte. For all female lymphocytes having HLA-DR molecule on its membrane, the blocking effect of female autoserum in the study group was significantly more expressed in relation to the control group. Thus, the effect of female autoserum is manifested in relation to the HLA-DR expression on its own lymphocytes, but not on the lymphocytes of the spouse

Thymic gland aspects in childhood: morpho-functional reciprocal relationships betwen thymus, nervous and endocrine system, in particular, with the somatotrophic axis hormones

Thymic gland (thymus) represents a huge mystery for biology, medicine (primarily immunology), including pediatric issues. Complexity of the study is determined by the multiplicity of integral connections of thymus with other components of immune system, neuroendocrine, hematopoietic systems, connective tissue, different organs and cells which provide appropriate barrier function. Discerning the direct thymic function from this continuum, or determining specific role of molecular factors (neuropeptides, growth hormone, etc.) upon the immune physiology represents a problem which is not yet resolved. In this review article dedicated to the current state of the problem, we consider the morphological and functional relationships between thymus, neuroendocrine system and, in particular, with hormones of the somatotropic axis. These interactions may also manifest by clinical heterogeneity which may be associated with impaired morphogenesis (organogenesis) at a very early stage of embryogenesis; namely, under the influence of gene family that determine the fate of each segment of the embryo-Hox genes which control the expression of other, functionally interconnected genes. Previously, T lymphocytes produced by the thymus and brain neurons have been shown to express the same antigen (Thy antigen), which was considered a specific antigen of T lymphocytes. A common molecular language, mediated by the molecules of intercellular interaction, was revealed which is used for the signal exchange between the cells, tissues and organs regulating the three mentioned systems (nervous, endocrine and immune). The interest of pediatricians in this field is associated with definite concept of human ontogenesis, from birth to elderly age, with thymic gland playing the main role, since antenatal period to early childhood. The main line of reasoning in this research area is not only theoretical, but also important from practical point of view. Since any critical involution of the thymus is accompanied by reduced number of produced and exported cells, a hormone-based therapy may be an alternative strategy to restore the organ by increasing thymocyte proliferation, and exporting mature T cells to peripheral lymphoid organs. Great opportunities have been opened in clinical immunology due to development of effective epistemological methods, e.g., genetic knock-out, transgenic animal models with human stem cell transfer, transplantation of hematopoietic and immunopoietic cells in primary and secondary immunodeficiencies, immune cell malignancies, autoinflammatory diseases, and, finally, infections of the immune system

Evolutionary aspects of thymology in pediatric practice

The thymus is now considered a derivative of the immune system being, to greater extent, its central organ. Immunodeficiency states and immune dysregulation also depend on the quality of the thymus, which may be determined both genetically and by fetopathic approach as well as due to the possibility and mode of its intravital injuries, age-related involution over different periods of life. Not accidentally, there are various morphometric bipolar states of the thymus gland in the pediatric population (3-7%), whereas its size may be sufficiently larger or smaller than the reference variable values. In certain cases, the phenomenon of thymomegaly (for example, in newborns) is considered a result of genetic errors (neuro-endocrine-immune syndrome with thymomegaly) induced by the mutated Hox genes. This syndrome may also be associated with congenital heart disorders. Moreover, the excessive morbidity in respiratory infections (commonly, viral by their etiology) among young children with bipolar thymus conditions remains the subject of sharp discussions. Some works assessing immune status in the children subjected to forced thymectomy, e.g., during heart surgery, yielded quite controversial results, even in cases of subtotal removal of thymus gland.Dialectically, the concepts of “morphology” and “organ function” could not be separated from one another. The morphometric transformations in organs (even transient ones) occuring within the range of &gt; 95 and &lt; 5 percentiles, should be almost always underlied by a certain pathomorphosis which require verification of their causes and origin. Even today, however, the assessment of thymus pathomorphology in the deceased children is not always critical, being often descriptive. This situation is, probably, associated with extreme complexity of thymic morphology assessment. The final point seems to be not set in the discussion about immunodeficiency states or immune dysregulation among children with bipolar thymus transformations. This is due to current absence of reliable immune-mediated biomarkers, the limited availability of genetic diagnostics in primary immunodeficiency conditions, and a decreased interest of clinical science in the issues of bipolar conditions of the thymus gland at the early age, in the absence of longitudinal observations in this category of patients, etc. In this article, the authors attempt to draw attention of researchers to this problem

ОСОБЕННОСТИ ИММУННОГО СТАТУСА У ДЕТЕЙ С ФУНКЦИОНАЛЬНЫМИ НАРУШЕНИЯМИ СЕРДЕЧНО-СОСУДИСТОЙ СИСТЕМЫ В УСЛОВИЯХ ЭКСПОЗИЦИИ АЛЮМИНИЕМ

Aim To estimate the prevalence of functional cardiovascular system disorders and immunological parameters in children living in the Irkutsk Region, a technogenic region of Southern Siberia.Methods A set of clinical, laboratory and instrumental, statistical and analytical methods were used in the study. Immunological parameters and the presence of functional cardiovascular system disorders were assessed in 63 children aged 5–11 years living in the technogenic region with aluminum exposure. The study group included children (n = 31) with functional changes in the cardiovascular system. Children (n = 32) without any functional changes in the cardiovascular system were enrolled in the control group. The functional status of the cardiovascular system was evaluated with the electrocardiography and physical examination. The immune parameters were measured with the flow cytometry and enzyme allegrosorbent testing. The analytical study of the chemical changes in the biomedia induced by aluminum exposure followed the national guidelines.Results Children permanently residing in the technogenic region with aluminum exposure suffer from mild anomalies of the heart development. These anomalies are associated reliably with the diseases of the blood and blood-forming organs involving the immune mechanism. The analytical study of the chemical changes in the biomedia showed that the study group has significantly elevated aluminum levels in blood and urine. Immune alterations have been found in the study, including a significant increase in the TNFR receptor, Bcl-2 protein, Treg cell differentiation clusters (CD4+CD25+CD127-) and CD3+CD25+. A significantly increased level of specific sensitization by the IgG criterion was established.Conclusion The study reported that functional cardiovascular system disorders among children living in the technogenic region with aluminum exposure are associated with alteration in the immune system. These alterations suggest the presence of the imbalance between apoptotic regulation and the initiation of adjuvant sensitivity to man-made haptens (aluminum).Цель Изучить встречаемость функциональных нарушений сердечно-сосудистой системы (ССС) и иммунологические показатели у детей, проживающих на техногенно-нагруженной территории юга Сибири (на примере Иркутской области).Материалы и методы В работе использованы клинические, лабораторные и инструментальные, статистические и аналитические методы. Проведено исследование иммунологических показателей, функционального состояния ССС 63 детей в возрасте 5–11 лет, проживающих на техногенно-нагруженной по алюминию территории. Группа наблюдения представлена детьми (n = 31), имеющими функциональные изменения ССС. Группу сравнения составили дети (n = 32), не имеющие указаний на функциональные отклонения со стороны ССС. Оценка функционального состояния ССС проводилась методами электрокардиографии и объективного обследования. Для исследования иммунных показателей использовались проточная цитометрия и аллергосорбентный метод. Химико-аналитическое исследование биосред на содержание алюминия проводили в соответствии с действующими в Российской Федерации методическими указаниями.Результаты Исследования показали, что функциональные нарушения ССС у детей, постоянно проживающих на техногенно-нагруженной по алюминию территории, характеризуются малыми аномалиями развития сердца и их достоверной ассоциацией с болезнями крови и кроветворных органов и состояний, вовлекающих иммунный механизм. Химико-аналитический анализ биосред показал, что у наблюдаемой группы детей достоверно повышено содержание алюминия в крови и моче. Иммунологические исследования состояния здоровья детского населения выявили наличие изменений со стороны иммунной системы: установлено достоверное повышение рецептора TNFR, белка Bcl-2, кластеров дифференцировки клетки Treg (CD4+CD25+CD127-) и CD3+CD25+. Установлен достоверно повышенный уровень специфической сенсибилизации по критерию IgG.Заключение В результате исследования показано, что функциональные отклонения в ССС у детей, проживающих на техногенно-нагруженной по алюминию территории, ассоциированы с изменениями показателей иммунной системы, характеризующими дисбаланс апоптотической регуляции с инициацией адъювантной чувствительности к техногенным гаптенам (алюминий)

ОСОБЕННОСТИ ЭПИДЕМИОЛОГИИ ВРОЖДЕННЫХ ПОРОКОВ СЕРДЦА У ДЕТЕЙ г. КЕМЕРОВО КАК КРУПНОГО ПРОМЫШЛЕННОГО ЦЕНТРА

Frequency of children with congenital heart diseases remains high in the Russian Federation. This pathology makes an essential contribution to perinatal and infantile mortality. Knowledge of epidemiology of various forms of congenital heart diseases will give the chance to develop new methods of forecasting, prenatal diagnostics and early effective surgical treatment of this pathology. Results of research of epidemiology of congenital heart diseases (according to recommendations of EUROCAT) are presented during 1993–2012 in Kemerovo. The trend of dynamics of various forms of congenital heart diseases was positive for the studied period. At extrapolation of the obtained data it is possible to expect them an annual gain on 7 ‰. The interrelation between factors of ecology and formation of congenital heart diseases at children is revealed in Kemerovo. Congenital heart diseases at children can be used, as indicator of externally environmental influence on health of the population KemerovoЧастота рождения детей с врожденными пороками сердца остается высокой в Российской Федерации. Эта патология вносит существенный вклад в перинатальную и младенческую смертность. Для разработки методов прогнозирования, пренатальной диагностики и раннего эффективного хирургического лечения необходимо знать особенности эпидемиологии различных нозологических форм врожденных пороков сердца. В настоящем исследовании представлены данные об эпидемиологии врожденных пороков сердца (согласно рекомендациям EUROCAT) в г. Кемерово за 1993–2012 гг. Выявлен положительный тренд динамики отдельных нозологических форм врожденных пороков сердца за исследуемый период. При экстраполировании полученных данных можно ожидать их ежегодного прироста на 7 промилле. Показана взаимосвязь между факторами среды обитания и частотой выявления врожденных пороков развития у детей на территории г. Кемерово. Врожденные пороки сердца у детей могут быть использованы как индикаторный показатель внешнесредового влияния на здоровье населения г. Кемерово

Модифицируемые и немодифицируемые факторы риска репротезирования митрального клапана

Highlights. In the present study, we conducted a retrospective analysis redo mitral valve replacement due to prosthesis failure. Predictors of adverse events and death have been analyzed. The quality of obtained predictors was verified using ROC analysis.Aim. To analyze predictors of adverse events and death in redo mitral procedure for treating mitral bioprostheses failure.Methods. The retrospective registry study of catamnesis of patients undergoing treatment for mitral valve prosthesis dysfunction was carried out. The age and gender of patients, medical history, underlying and comorbid diseases, features of primary replacement and reoperation, durability of the primary prosthesis, adverse events and death after redo mitral valve replacement and others (more than 30 factors) were taken into account. Stepwise logistic regression was used for statistical processing. The quality of obtained predictors was verified using ROC analysis.Results. The results of the study have revealed that there are modifiable risk factors such as cardiopulmonary bypass time, ischemia time, and nonmodifiable risk factors like reoperation, baseline severity of the patient's condition, complications of median resternotomy, concomitant interventions on aortic valve during reoperation. Moreover, treating atrial fibrillation during primary replacement proved to have an overall protective effect.Conclusion. Тhe only modifiable factors that can be influenced during redo mitral valve replacement due to biological prosthesis failure are cardiopulmonary bypass duration and aortic cross-clamping time.Основные положения. Проведен ретроспективный анализ повторных операций по поводу дисфункции протеза в митральной позиции. Изучены предикторы риска неблагоприятных событий и летального исхода. Качество полученных предикторных характеристик верифицировано при помощи ROC-анализа.Цель. Изучение предикторов риска неблагоприятных событий и летального исхода при репротезировании вследствие дисфункции протеза митрального клапана.Материалы и методы. Проведено ретроспективное регистровое исследование катамнеза пациентов, оперированных по поводу дисфункции протеза митрального клапана. Учитывали возраст и пол пациентов, показатели анамнеза жизни, основного и сопутствующих заболеваний, особенности первичного и повторного протезирования, срок функционирования первичного протеза, неблагоприятные события, летальный исход после повторной операции и другие (более 30 факторов). Для статистической обработки использовали логистическую регрессию (пошаговый вариант). Качество полученных предикторных характеристик верифицировали при помощи ROC-анализа.Результаты. Выявлены факторы риска, которые отнесены к модифицируемым (время искусственного кровообращения, продолжительность ишемии миокарда) и немодифицируемым (фактор реоперации, исходная тяжесть состояния пациента, осложнения рестернотомии, сопутствующие вмешательства на аортальном клапане при повторной операции). Кроме того, определен протективный характер коррекции фибрилляции предсердий во время первичной операции.Заключение. Модифицируемыми факторами, на которые можно воздействовать во время репротезирования митрального клапана по поводу дисфункции механического протеза, являются длительность искусственного кровообращения и время ишемии миокарда