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Aim: WHIM (warts, hypogammaglobulinaemia, infections and myelokathexis) syndrome is a rare combined primary immunodeficiency disease caused by gain‐of‐function (GOF) mutations in the chemokine receptor CXCR4 and includes severe neutropenia as a common feature. Neutropenia is a known risk factor for periodontitis; however, a detailed periodontal evaluation of a WHIM syndrome cohort is lacking. This study aimed to establish the evidence base for the periodontal status of patients with WHIM syndrome. Materials and Methods: Twenty‐two adult WHIM syndrome patients and 22 age‐ and gender‐matched healthy volunteers (HVs) were evaluated through a comprehensive medical and periodontal examination. A mouse model of WHIM syndrome was assessed for susceptibility to naturally progressing or inducible periodontitis. Results: Fourteen patients with WHIM syndrome (63.6%) and one HV (4.5%) were diagnosed with Stage III/IV periodontitis. No WHIM patient presented with the early onset, dramatic clinical phenotypes typically associated with genetic forms of neutropenia. Age, but not the specific CXCR4 mutation or absolute neutrophil count, was associated with periodontitis severity in the WHIM cohort. Mice with a Cxcr4 GOF mutation did not exhibit increased alveolar bone loss in spontaneous or ligature‐induced periodontitis. Conclusions: Overall, WHIM syndrome patients presented with an increased severity of periodontitis despite past and ongoing neutrophil mobilization treatments. GOF mutations in CXCR4 may be a risk factor for periodontitis in humans. [ABSTRACT FROM AUTHOR]

Antifibrinolytic drugs are used extensively for on-demand treatment of severe acute bleeding. Controlling fibrinolysis may also be an effective strategy to prevent or lessen chronic recurring bleeding in bleeding disorders such as hemophilia A (HA), but current antifibrinolytics have unfavorable pharmacokinetic profiles. Here, we developed a long-lasting antifibrinolytic using small interfering RNA (siRNA) targeting plasminogen packaged in clinically used lipid nanoparticles (LNPs) and tested it to determine whether reducing plasmin activity in animal models of HA could decrease bleeding frequency and severity. Treatment with the siRNA-carrying LNPs reduced circulating plasminogen and suppressed fibrinolysis in wild-type and HA mice and dogs. In HA mice, hemostatic efficacy depended on the injury model; plasminogen knockdown improved hemostasis after a saphenous vein injury but not tail vein transection injury, suggesting that saphenous vein injury is a murine bleeding model sensitive to the contribution of fibrinolysis. In dogs with HA, LNPs carrying siRNA targeting plasminogen were as effective at stabilizing clots as tranexamic acid, a clinical antifibrinolytic, and in a pilot study of two dogs with HA, the incidence of spontaneous or excess bleeding was reduced during 4 months of prolonged knockdown. Collectively, these data demonstrate that long-acting antifibrinolytic therapy can be achieved and that it provides hemostatic benefit in animal models of HA. Editor's summary: Patients with hemophilia A suffer from spontaneous and excessive bleeding that can be treated with antifibrinolytics, but the short half-life of such drugs limits their use to on-demand treatment. Here, Strilchuk and colleagues packaged small interfering RNAs against plasminogen into lipid nanoparticles, showing that a single dose could reduce circulating plasminogen and suppress fibrinolysis for several weeks in mice. Prophylactic treatment led to improved hemostasis after saphenous vein injury in a mouse model of hemophila A, and 4 months of plasminogen knockdown decreased spontaneous and excess bleeding events in two dogs with hemophilia A without evidence of severe toxicity, suggesting that this approach should be further studied in the context of hemophilia A and other diseases characterized by high fibrinolysis. —Melissa L. Norton [ABSTRACT FROM AUTHOR]

Macrophage plasticity, cellular origin, and phenotypic heterogeneity are perpetual challenges for studies addressing the biology of this pivotal immune cell in development, homeostasis, and tissue remodeling/repair. Consequently, a myriad of macrophage subtypes has been described in these contexts. To facilitate the identification of functional macrophage subtypes in vivo, here we used a flow cytometry-based assay that allows for detailed phenotyping of macrophages engaged in extracellular matrix (ECM) degradation. Of the five macrophage subtypes identified in the remodeling dermis by using this assay, collagen degradation was primarily executed by Ly6C−CCR2+ and Ly6C−CCR2low macrophages via mannose receptor-dependent collagen endocytosis, while Ly6C+CCR2+ macrophages were the dominant fibrin-endocytosing cells. Unexpectedly, the CCL2/MCP1-CCR2 signaling axis was critical for both collagen and fibrin degradation, while collagen degradation was independent of IL-4Ra signaling. Furthermore, the cytokine GM-CSF selectively enhanced collagen degradation by Ly6C+CCR2+ macrophages. This study reveals distinct subsets of macrophages engaged in ECM turnover and identifies novel wound healing-associated functions for CCL2 and GM-CSF inflammatory cytokines. Keywords: Collagen degradation, Extracellular matrix endocytosis, Fibrin degradation, Interleukin-13, Mannose receptor/CD206, uPARAP/Endo180

Summary: Mucosal tissues are constantly exposed to the outside environment. They receive signals from the commensal microbiome and tissue‐specific triggers including alimentary and airborne elements and are tasked to maintain balance in the absence of inflammation and infection. Here, we present neutrophils as sentinel cells in mucosal immunity. We discuss the roles of neutrophils in mucosal homeostasis and overview clinical susceptibilities in patients with neutrophil defects. Finally, we present concepts related to specification of neutrophil responses within specific mucosal tissue microenvironments. [ABSTRACT FROM AUTHOR]

Queue length estimation is imperative as a tool of designing traffic characteristics of an intersection while queue length prediction enables to identify the traffic congestion in advance. This study was aimed to estimate the queue length at signalized intersections having heterogeneous traffic conditions. Furthermore, the study predicts the vehicle queue length of a different intersection with using the estimation results. Therefore, two case studies were conducted in two locations for the queue estimation and queue prediction respectively. The queue estimation study was conducted in a signalized pedestrian crossing in Malabe, Sri Lanka and the queue prediction in a signalized intersection in Armour Street, Sri Lanka where the vehicle density reflected the intense heterogeneity. Heterogeneous traffic conditions were defined as the diversified vehicle composition. The heterogeneity was assimilated with the consideration of Passenger Car Units (PCU) in the measurements of the traffic flow. The influential factors of the queue length were contemplated with the arrival flow, discharge flow and the signal configuration. The time-series analysis integrated the unrestricted Vector Auto Regression (VAR) models as the queue length and the other considered variables which depends on the time. Moreover, the results have indicated a higher accuracy in the queue estimation, practically applied for the prediction constituting to the traffic characteristics of the formed vehicle queue. [ABSTRACT FROM AUTHOR]

Milk powder has become an essential component of the diet of Sri Lankan consumers. However, recent information related to the contamination of imported milk powder with hazardous elements has made a considerable impact on the preference of milk powder brands among consumers in Sri Lanka. Thereby, the current study aims to explore the effect of selected marketing mix antecedents on consumer brand preference for milk powder. Primary data was collected through an online survey using a Google form-based structured questionnaire. The convenience sampling technique was used in selecting the sample of 100 milk powder consumers. The collected data were analyzed by SMART PLS using partial least squares. The findings revealed that brand personality and country of origin have a significant effect on milk powder brand preference. Furthermore, the study suggests a significant positive influence of brand preference on brand loyalty to milk powder. Moreover, results revealed that consumers prefer domestically produced milk powder brands over imported brands. The findings of this study are of great significance for local milk powder companies and marketing practitioners to implement strategies in order to enhance the availability and marketing of domestically manufactured milk powder. Further, marketers should pay more attention to the brand personality in order to attract more consumers to their respective milk powder brands. [ABSTRACT FROM AUTHOR]

Summary: Periodontitis is a common human inflammatory disease. In this condition, microbiota trigger excessive inflammation in oral mucosal tissues surrounding the dentition, resulting in destruction of tooth‐supporting structures (connective tissue and bone). While susceptibility factors for common forms of periodontitis are not clearly understood, studies in patients with single genetic defects reveal a critical role for tissue neutrophils in disease susceptibility. Indeed, various genetic defects in the development, egress from the bone marrow, chemotaxis, and extravasation are clearly linked to aggressive/severe periodontitis at an early age. Here, we provide an overview of genetic defects in neutrophil biology that are linked to periodontitis. In particular, we focus on the mechanisms underlying Leukocyte Adhesion Deficiency‐I, the prototypic Mendelian defect of impaired neutrophil extravasation and severe periodontitis. [ABSTRACT FROM AUTHOR]

The article presents the discussion on determining the mechanistic link between fibrin deposition and oral mucosal immunopathology. Topics include congenital deficiency in plasminogen, the proenzyme form of the abundant plasma protease plasmin leading to severe mucosal inflammatory disease; and oral immunopathology in plasminogen deficiency prevented by genetic or pharmacological elimination of the fibrin precursor.

Bacillus anthracis lethal toxin and edema toxin are binary toxins that consist of a common cell-binding moiety, protective antigen (PA), and the enzymatic moieties, lethal factor (LF) and edema factor (EF). PA binds to either of two receptors, capillary morphogenesis protein-2 (CMG-2) or tumor endothelial marker-8 (TEM-8), which triggers the binding and cytoplasmic translocation of LF and EF. However, the distribution of functional TEM-8 and CMG-2 receptors during anthrax toxin intoxication in animals has not been fully elucidated. Herein, we describe an assay to image anthrax toxin intoxication in animals, and we use it to visualize TEM-8- and CMG-2-dependent intoxication in mice. Specifically, we generated a chimeric protein consisting of the N-terminal domain of LF fused to a nuclear localization signal-tagged Cre recombinase (LFn-NLS-Cre). When PA and LFn-NLS-Cre were coadministered to transgenic mice expressing a red fluorescent protein in the absence of Cre and a green fluorescent protein in the presence of Cre, intoxication could be visualized at single-cell resolution by confocal microscopy or flow cytometry. Using this assay, we found that: (a) CMG-2 is critical for intoxication in the liver and heart, (b) TEM-8 is required for intoxication in the kidney and spleen, (c) CMG-2 and TEM-8 are redundant for intoxication of some organs, (d) combined loss of CMG-2 and TEM-8 completely abolishes intoxication, and (e) CMG-2 is the dominant receptor on leukocytes. The novel assay will be useful for basic and clinical/translational studies of Bacillus anthracis infection and for clinical development of reengineered toxin variants for cancer treatment. [ABSTRACT FROM AUTHOR]

Purpose: Studies in patients with single gene mutations reveal the role of specific genes and pathways in human health and disease. In this sense, studies in patients with genetic defects leading to periodontitis become important toward the understanding of genetic factors linked to periodontitis susceptibility. WHIM syndrome (Warts, Hypogammaglobulinemia, Infections, and Myelokathexis syndrome) is an autosomal dominant syndrome caused by gain of function (GOF) mutations in the chemokine receptor CXCR4. While severe periodontitis in early life has been reported in multiple cases of WHIM syndrome, a comprehensive characterization of periodontal clinical status has not been performed in a large WHIM cohort to date. Furthermore, mechanisms underlying periodontitis susceptibility in WHIM syndrome are not fully delineated. The purpose of this study was to characterize the extent of periodontal pathogenesis in patients with WHIM Syndrome immune dysfunction comparted to age-gender matched healthy controls through clinical parameters. Methods: A cohort of WHIM patients (n=23) and age matched healthy volunteers (n=23) were clinically evaluated at the NIH hospital. Clinical parameters included probing depth, clinical attachment loss, bleeding upon probing, and missing teeth as well as radiographic evidence of bone loss. Results: Patients with WHIM syndrome present with increased susceptibility to periodontitis. Thirty percent of WHIM patients presented with severe disease. WHIM patients had significantly increased mean probing depths p<0.0001, clinical attachment loss p<0.0001, percentage of sites bleeding on probing p=0.0009 and number of missing teeth 3.65+4.6 compared to age/gender matched healthy volunteers 1.7+1.58. Conclusions: GOF mutations in CXCR4 lead to periodontitis susceptibility. Further studies are exploring mechanisms underlying this phenotype. [ABSTRACT FROM AUTHOR]