Disruptive Selection of Human Immunostimulatory and Immunosuppressive Genes Both Provokes and Prevents Rheumatoid Arthritis, Respectively, as a Self-Domestication Syndrome

Using our previously published Web service SNP_TATA_Comparator, we conducted a genome-wide study of single-nucleotide polymorphisms (SNPs) within core promoters of 68 human rheumatoid arthritis (RA)-related genes. Using 603 SNPs within 25 genes clinically associated with RA-comorbid disorders, we predicted 84 and 70 candidate SNP markers for overexpression and underexpression of these genes, respectively, among which 58 and 96 candidate SNP markers, respectively, can relieve and worsen RA as if there is a neutral drift toward susceptibility to RA. Similarly, we predicted natural selection toward susceptibility to RA for 8 immunostimulatory genes (e.g., IL9R) and 10 genes most often associated with RA (e.g., NPY). On the contrary, using 25 immunosuppressive genes, we predicted 70 and 109 candidate SNP markers aggravating and relieving RA, respectively (e.g., IL1R2 and TGFB2), suggesting that natural selection can simultaneously additionally yield resistance to RA. We concluded that disruptive natural selection of human immunostimulatory and immunosuppressive genes is concurrently elevating and reducing the risk of RA, respectively. So, we hypothesize that RA in human could be a self-domestication syndrome referring to evolution patterns in domestic animals. We tested this hypothesis by means of public RNA-Seq data on 1740 differentially expressed genes (DEGs) of pets vs. wild animals (e.g., dogs vs. wolves). The number of DEGs in the domestic animals corresponding to worsened RA condition in humans was significantly larger than that in the related wild animals (10 vs. 3). Moreover, much less DEGs in the domestic animals were accordant to relieved RA condition in humans than those in the wild animals (1 vs. 8 genes). This indicates that the anthropogenic environment, in contrast to a natural one, affects gene expression across the whole genome (e.g., immunostimulatory and immunosuppressive genes) in a manner that likely contributes to RA. The difference in gene numbers is statistically significant as confirmed by binomial distribution (p < 0.01), Pearson’s χ2 (p < 0.01), and Fisher’s exact test (p < 0.05). This allows us to propose RA as a candidate symptom within a self-domestication syndrome. Such syndrome might be considered as a human’s payment with health for the benefits received during evolution

Healthy pediatric platelets are moderately hyporeactive in comparison with adults’ platelets

Studies on platelet function in children older than neonatal period are few and their results are controversial. The pediatric platelets were alternatively reported to be more active or less active than adults’ ones. We compared platelet function in the several age groups of children to adults and evaluated the age when platelet function reaches the adults’ status. The study included 76 healthy children and 49 healthy adult volunteers. Types of platelet activation used included: collagen-related peptide (CRP) and PAR-1 activating peptide SFLLRN; SFLLRN, PAR-4 activating peptide AYPGKF and adenosine diphosphate (ADP); ADP. The parameters determined included forward (FSC) and side scatter (SSC), CD42b, CD61, CD62P, PAC-1, annexin V binding and mepacrine release levels. Resting pediatric platelets were similar to adults’ platelets except for 1.2-fold decreased FSC and dense granules volume in youngest children, and 2.5-fold increased annexin V level in children aged 1–10 years. After CRP+SFLLRN stimulation, pediatric platelets had a 1.2-fold lower alpha- and 1.1-fold lower dense granule release than adults. For SFLLRN+AYPGKF+ADP stimulation, this was observed only for youngest children. The response to ADP stimulation was identical for pediatric platelets and adults. Pediatric platelets have lower granular release than adults’ platelets, which persists until the age of 18

Platelet function and blood coagulation system status in childhood essential thrombocythemia

Childhood essential thrombocythemia (ET) is a rare chronic myeloproliferative disorder. The quality of life of ET patients may decrease as a result of ischemic and hemorrhagic complications of unclear origin. Our goal was to characterize the hemostatic system in children with ET. We genotyped and investigated blood samples from 20 children with ET in a prospective case series study using platelet aggregation, functional flow cytometry (FC) assay and standard clotting assays. Three children had a JAK2V617F mutation, 4 had mutations in CALR and 13 were triple-negative. Myelofibrosis in stage 1-2 was detected in 3 children. Three patients had bleeding episodes and seven had ischemic events. Aggregation in response to collagen, adenosine diphosphate, and ristomycin was decreased in all patients. In FC, significant changes in the whole patient group compared to the healthy children control group were decrease in the resting forward scatter and PAC1 binding (activated GPIIb/IIIa) level. For the activated platelets, dense granules release (by mepacrine), PAC1, and GPIIb/IIIa levels were significantly decreased. GPIb/V/IX, P-selectin, and phosphatidylserine levels manifested only moderate differences. Forward and side scatter changes in response to stimulation (representing shape change) and dense granules release were significantly lower in the 3 patients with bleeding than in the 17 patients without hemorrhage. Activated partial thromboplastin time was slightly prolonged, prothrombin index was slightly shortened and thrombin time was normal, while fibrinogen was mildly decreased in the ET patients. It could be concluded that the observed platelet function defects could be related to bleeding in ET, and be potentially used as a marker

Flow cytometry for pediatric platelets

The ability of platelets to carry out their hemostatic function can be impaired in a wide range of inherited and acquired conditions: trauma, surgery, inflammation, pre-term birth, sepsis, hematological malignancies, solid tumors, chemotherapy, autoimmune disorders, and many others. Evaluation of this impairment is vitally important for research and clinical purposes. This problem is particularly pronounced in pediatric patients, where these conditions occur frequently, while blood volume and the choice of blood collection methods could be limited. Here we describe a simple flow cytometry-based screening method of comprehensive whole blood platelet function testing that was validated for a range of pediatric and adult samples (n = 31) in the hematology hospital setting including but not limited to: classic inherited platelet function disorders (Glanzmann’s thrombasthenia; Bernard-Soulier, Wiscott-Aldrich, and Hermasky-Pudlak syndromes, MYH9-dependent thrombocytopenia), healthy and pre-term newborns, acute and chronic immune thrombocytopenia, chronic lympholeukemia, effects of therapy on platelet function, etc. The method output includes levels of forward and side scatter, levels of major adhesion and aggregation glycoproteins Ib and IIb-IIIa, active integrins’ level based on PAC-1 binding, major alpha-granule component P-selectin, dense granule function based on mepacrine uptake and release, and procoagulant activity quantified as a percentage of annexin V-positive platelets. This analysis is performed for both resting and dual-agonist-stimulated platelets. Preanalytical and analytical variables are provided and discussed. Parameter distribution within the healthy donor population for adults (n = 72) and children (n = 17) is analyzed

Synthesis and Photophysical Properties of Novel Meta-Conjugated Organic Molecules with 1,3,5-Benzene Branching Units

The synthesis and photophysical investigation of three novel meta-conjugated molecules based on 3,1,2-benzothiadiazole and thiophene-2,5-diyl derivatives linked through 1,3,5-benzene branching units are described. Each of them is a symmetrical molecule with two branching units, four identical lateral thiophene-containing fragments, and one central benzothiadiazole-containing fragment. To study the effect of the chemical structure on their photophysical properties, the molecules with different linearly conjugated lateral and central fragments due to incorporation of additional thiophene rings were synthesized and compared. It was shown that absorption spectra of the meta-conjugated molecules can be represented as a sum of absorption bands of model compounds for their peripheral and central fragments containing a common benzene ring being branched at the 1,3,5-benzene unit in the meta-conjugated molecules. Therefore, they cannot be considered simply as isolated π-conjugated systems of their peripheral and central fragments. Instead, DFT calculations showed that several transitions between the orbitals located in different regions of the meta-conjugated molecule are responsible for the formation of their absorption spectra, and they strongly depend on the degree of their overlapping. Theoretical absorption spectra reconstructed from the DFT data demonstrated a good agreement with the experimental results: the transitions with larger oscillator strength correspond to the bands with higher molar extinction coefficients and vice versa. It was shown that luminescence spectral maxima of the meta-conjugated molecules monotonically shift to the lower energy from 489 to 540 and 613 nm with increasing the number of thiophene rings in the peripheral and central fragments, respectively. However, luminescence quantum yield of the meta-conjugated molecules critically depends on the length of linearly conjugated fragments in its structure decreasing from 24% to 1.3% with increasing the number of thiophene rings in the lateral fragments but increasing to 90% in the molecule with more thiophene rings in both types of the fragments. The results obtained are well correlated to the ratio of radiative and nonradiative deactivation rate constants of the meta-conjugated molecules that indicates a high rate of internal conversion between the excited states corresponding to different fragments of the molecule. The CV measurements allowed estimating the HOMO, LUMO, and bandgap values of the target and model compounds, which confirm the presence of meta-conjugation within the molecules investigated. Thus, connection of linearly conjugated fragments through meta-positions (meta-conjugation) of a benzene ring leads to an intermediate option between fully conjugated and nonconjugated molecules due to partial delocalization of electron density through the 1,3,5-substituted benzene branching center