Cysteinyl leukotriene receptor-1 as a potential target for host-directed therapy during chronic schistosomiasis in murine model.

Schistosomiasis remains the most devastating neglected tropical disease, affecting over 240 million people world-wide. The disease is caused by the eggs laid by mature female worms that are trapped in host's tissues, resulting in chronic Th2 driven fibrogranulmatous pathology. Although the disease can be treated with a relatively inexpensive drug, praziquantel (PZQ), re-infections remain a major problem in endemic areas. There is a need for new therapeutic drugs and alternative drug treatments for schistosomiasis. The current study hypothesized that cysteinyl leukotrienes (cysLTs) could mediate fibroproliferative pathology during schistosomiasis. Cysteinyl leukotrienes (cysLTs) are potent lipid mediators that are known to be key players in inflammatory diseases, such as asthma and allergic rhinitis. The present study aimed to investigate the role of cysLTR1 during experimental acute and chronic schistosomiasis using cysLTR1-/- mice, as well as the use of cysLTR1 inhibitor (Montelukast) to assess immune responses during chronic Schistosoma mansoni infection. Mice deficient of cysLTR1 and littermate control mice were infected with either high or low dose of Schistosoma mansoni to achieve chronic or acute schistosomiasis, respectively. Hepatic granulomatous inflammation, hepatic fibrosis and IL-4 production in the liver was significantly reduced in mice lacking cysLTR1 during chronic schistosomiasis, while reduced liver pathology was observed during acute schistosomiasis. Pharmacological blockade of cysLTR1 using montelukast in combination with PZQ reduced hepatic inflammation and parasite egg burden in chronically infected mice. Combination therapy led to the expansion of Tregs in chronically infected mice. We show that the disruption of cysLTR1 is dispensable for host survival during schistosomiasis, suggesting an important role cysLTR1 may play during early immunity against schistosomiasis. Our findings revealed that the combination of montelukast and PZQ could be a potential prophylactic treatment for chronic schistosomiasis by reducing fibrogranulomatous pathology in mice. In conclusion, the present study demonstrated that cysLTR1 is a potential target for host-directed therapy to ameliorate fibrogranulomatous pathology in the liver during chronic and acute schistosomiasis in mice.

Environmental and microbial factors influence affective and cognitive behavior in C57BL/6 sub-strains.

C57BL/6 mice are one of the most widely used inbred strains in biomedical research. Early separation of the breeding colony has led to the development of several sub-strains. Colony separation led to genetic variation development driving numerous phenotypic discrepancies. The reported phenotypic behavior differences between the sub-strains were, however; not consistent in the literature, suggesting the involvement of factors other than host genes. Here, we characterized the cognitive and affective behavior of C57BL/6J and C57BL/6N mice in correlation with the immune cell profile in the brain. Furthermore, faecal microbiota transfer and mice co-housing techniques were used to dissect microbial and environmental factors' contribution, respectively, to cognitive and affective behavior patterns. We first noted a unique profile of locomotor activity, immobility pattern, and spatial and non-spatial learning and memory abilities between the two sub-strains. The phenotypic behavior profile was associated with a distinct difference in the dynamics of type 2 cytokines in the meninges and brain parenchyma. Analysing the contribution of microbiome and environmental factors to the noted behavioral profile, our data indicated that while immobility pattern was genetically driven, locomotor activity and cognitive abilities were highly sensitive to alterations in the gut microbiome and environmental factors. Changes in the phenotypic behavior in response to these factors were associated with changes in immune cell profile. While microglia were highly sensitive to alteration in gut microbiome, immune cells in meninges were more resilient. Collectively, our findings demonstrated a direct impact of environmental conditions on gut microbiota which subsequently impacts the brain immune cell profile that could modulate cognitive and affective behavior. Our data further highlight the importance of characterizing the laboratory available strain/sub-strain to select the most appropriate one that fits best the study purpose.

Furlow Palatoplasty and Tonsillectomy for Treating Patients With Submucous Cleft Palate and Tonsillar Hypertrophy: A One-Stage Procedure.

BACKGROUND: Children with cleft palate are more liable to have obstructive sleep apnea than children with normal palate due to narrow airways. Tonsillar hypertrophy is a common cause of pediatric obstructive sleep apnea; hence, it is not surprising to be encountered during cleft palate repair. The aim of this study was to evaluate the feasibility of tonsillectomy and Furlow palatoplasty performed as a 1-stage operation in patients presenting with submucous cleft palate (SMCP) and tonsillar hypertrophy. MATERIALS AND METHODS: Eleven pediatric patients with SMCP and hypertrophied tonsils were included in this case series study. Furlow palatoplasty and tonsillectomy were performed for the patients in 1 sitting. The evaluation of velopharyngeal function was done preoperatively and postoperatively via auditory-perceptual-assessment, nasometry, and flexible nasopharyngoscopy. In addition, the Epworth sleepiness scale for children/adolescents was administered to the parents to assess daytime sleepiness of their children. RESULTS: The speech improved postoperatively. Auditory-perceptual-assessment showed significant reductions in hypernasal speech, nasal air escape, and weak pressure consonants. In addition, nasometry revealed significantly decreased nasalance scores for nasal and oral sentences. A postoperative increased velar movement was observed with a significant improvement in velopharyngeal closure. The preoperative Epworth sleepiness scale for children/adolescents assessment revealed excessive daytime sleepiness in 8 patients, with significant improvement of scores postoperatively. CONCLUSIONS: Removal of hypertrophied tonsils during the repair of SMCP with Furlow palatoplasty did not negatively affect speech outcome or velar movement postoperatively. It is logical to perform both procedures simultaneously in 1 sitting to avoid postoperative sleep-related breathing disorder, which may necessitate a second stage operation.

Type 2 immunity: a two-edged sword in schistosomiasis immunopathology.

Schistosomiasis is the second most debilitating neglected tropical disease globally after malaria, with no available therapy to control disease-driven immunopathology. Although schistosomiasis induces a markedly heterogenous immune response, type 2 immunity is the dominating immune response following oviposition. While type 2 immunity has a crucial role in granuloma formation and host survival during the acute stage of disease, its chronic activation can result in tissue scarring, fibrosis, and organ impairment. Here, we discuss recent advances in schistosomiasis, demonstrating how different immune and non-immune cells and signaling pathways are involved in the induction, maintenance, and regulation of type 2 immunity. A better understanding of these immune responses during schistosomiasis is essential to inform the potential development of candidate therapeutic strategies that fine-tune type 2 immunity to ideally modulate schistosomiasis immunopathology.

Schistosoma mansoni infection induces plasmablast and plasma cell death in the bone marrow and accelerates the decline of host vaccine responses.

Schistosomiasis is a potentially lethal parasitic disease that profoundly impacts systemic immune function in chronically infected hosts through mechanisms that remain unknown. Given the immunoregulatory dysregulation experienced in infected individuals, this study examined the impact of chronic schistosomiasis on the sustainability of vaccine-induced immunity in both children living in endemic areas and experimental infections in mice. Data show that chronic Schistosoma mansoni infection impaired the persistence of vaccine specific antibody responses in poliovirus-vaccinated humans and mice. Mechanistically, schistosomiasis primarily fostered plasmablast and plasma cell death in the bone marrow and removal of parasites following praziquantel treatment reversed the observed cell death and partially restored vaccine-induced memory responses associated with increased serum anti-polio antibody responses. Our findings strongly suggest a previously unrecognized mechanism to explain how chronic schistosomiasis interferes with an otherwise effective vaccine regimen and further advocates for therapeutic intervention strategies that reduce schistosomiasis burden in endemic areas prior to vaccination.

Nasopharyngeal Polyp in a Patient With Submucous Cleft Palate.

Encountering a nasopharyngeal polyp in a patient with submucous cleft palate (SMCP) is a difficult problem, as the lesion could support the weak palate. Removal of this lesion may unmask the SMCP with consequent worsening of speech nasality. Nasal septal polyp protruding to the nasopharynx in a patient with SMCP has not been reported before in the literature. This report describes a septal polyp arising from the posterior border of the nasal septum and protruding in the nasopharynx in a 16-year-old girl with submucous cleft palate. The polyp appeared to support the weak palate, and they acted as a ball and socket during speech articulation. Removal of this polyp may result in velopharyngeal insufficiency. Trans-nasal endoscopic removal of the polyp with obturation of the velopharyngeal port with a superiorly-based pharyngeal flap was performed in the same sitting. Pre- and postoperative speech evaluation using auditory perceptual assessment and nasometry revealed no worsening of nasality, also the patient reported improvement of her nasal breathing. We concluded that, the presence of a nasopharyngeal polyp in a patient with SMCP may compensate the speech problem. Removal of the polyp and treatment of SMCP by a pharyngeal flap in one-sitting is an effective procedure without adverse effect on patient's speech.

Subjective Smell Assessment as An Office-based Rapid Procedure In COVID-19 Era.

ABSTRACT: A recent history of smell disorder may be a potential predictor for COVID-19. The authors used a subjective olfaction score that was demonstrated on a hard paper-bar. The authors examined 480 patients who were attending the outpatient clinic. Ninety-seven patients (20.2%) demonstrated variable degrees of recent smell disorder. For those patients, lab testing including nasopharyngeal swab for real-time polymerase chain reaction (RT-PCR) was performed. Eighty-eight of them (90.7%) have been confirmed to be COVID-19 positive. Although psychophysical testing is more reliable, subjective assessment of smell is a rapid procedure and can be used as an office-based method for patients' screening in COVID-19 era. Smell disorder could be an alarming sign for COVID-19 even with absent characteristic symptoms.

Batf2 differentially regulates tissue immunopathology in Type 1 and Type 2 diseases.

Basic leucine zipper transcription factor 2 (Batf2) activation is detrimental in Type 1-controlled infectious diseases, demonstrated during infection with Mycobacterium tuberculosis (Mtb) and Listeria monocytogenes Lm. In Batf2-deficient mice (Batf2-/-), infected with Mtb or Lm, mice survived and displayed reduced tissue pathology compared to infected control mice. Indeed, pulmonary inflammatory macrophage recruitment, pro-inflammatory cytokines and immune effectors were also decreased during tuberculosis. This explains that batf2 mRNA predictive early biomarker found in active TB patients is increased in peripheral blood. Similarly, Lm infection in human macrophages and mouse spleen and liver also increased Batf2 expression. In striking contrast, Type 2-controlled schistosomiasis exacerbates during infected Batf2-/- mice with increased intestinal fibro-granulomatous inflammation, pro-fibrotic immune cells, and elevated cytokine production leading to wasting disease and early death. Together, these data strongly indicate that Batf2 differentially regulates Type 1 and Type 2 immunity in infectious diseases.

The Foxp3+ regulatory T-cell population requires IL-4Rα signaling to control inflammation during helminth infections.

Forkhead box P3 (Foxp3+) regulatory T (Treg)-cell function is controlled by environmental cues of which cytokine-mediated signaling is a dominant component. In vivo, interleukin-4 (IL-4)-mediated signaling via IL-4 receptor alpha (IL-4Rα) mediates Treg cell transdifferentiation into ex-Foxp3 T helper 2 (Th2) or T helper 17 (Th17) cells. However, IL-4-mediated signaling also reinforces the Foxp3 Treg compartment in vitro. We generated Foxp3-specific IL-4Rα-deficient mice and demonstrated differential efficiency of IL-4Rα deletion in male (approximately 90%) and female (approximately 40%) animals, because of cyclic recombinase (Cre)-mediated X-linked foxp3 inactivation. Irrespective of the degree of IL-4Rα deletion within the Foxp3+ Treg cell population, mice showed exacerbation of immune effector responses with aggravated tissue pathology in tissue-dwelling helminth infections (Schistosoma mansoni or Nippostrongylus brasiliensis). Mechanistically, IL-4Rα deletion in males and females led to a reduced expression of Foxp3 and subsequently an impaired accumulation of Foxp3+ Treg cells to inflamed tissues. In-depth cellular typing by flow cytometry revealed that the impairment of IL-4Rα-mediated signaling during helminth infections decreased the ability of central Treg cells to convert into effector Treg (eTreg) cells and caused a significant down-regulation of markers associated with Treg cell migration (C-X-C motif chemokine receptor 3 [CXCR3]) and accumulation in inflamed tissues (GATA binding protein 3 [GATA3]) as well as survival (B cell lymphoma 2 [Bcl-2]). These findings unprecedentedly, to our knowledge, uncover a role for IL-4Rα signaling in the positive regulation of Foxp3+ Treg cell function in vivo. Complementing our past knowledge on a widely reported role for IL-4Rα signaling in the negative regulation and transdifferentiation of Foxp3+ Treg cells in vivo, our present findings reveal the host requirement for an intact, but not reduced or potentiated, IL-4Rα-mediated signaling on Foxp3+ Treg cells to optimally control inflammation during helminth infections.

Interleukin-4 Receptor Alpha Expressing B Cells Are Essential to Down-Modulate Host Granulomatous Inflammation During Schistosomasis.

Schistosomiasis (bilharzia) is a parasitic helminth disease that can cause severe inflammatory pathology leading to organ damage in humans. Failure of the host to regulate egg-driven granulomatous inflammation causes host morbidity during chronic infection with Schistosoma mansoni. Although the importance of B cells in regulating pathology during chronic infection has been well defined, the specific contribution of IL-4Rα-expressing B cells is still unknown. To address this, we examined B cell-specific IL-4Rα-deficient (mb1creIL-4Rα-/lox) mice in three experimental models of schistosomiasis: high-dose (100 cercariae), low dose (30 cercariae), and a synchronous egg challenge. In the high dose model, we found that mice deficient in IL-4Rα-expressing B cells were more susceptible to acute schistosomiasis than B cell-deficient (µMT) mice, succumbing to infection at the acute stage whereas µMT mice survived until the chronic stage. An S. mansoni egg challenge model demonstrated that deleting IL-4Rα expression specifically on B cells resulted in increased lung granulomatous pathology, suggesting a role for this B cell subset in controlling granulomatous pathology. In agreement with this, a low dose model of schistosomiasis-which mimics the course of clinical chronic disease-demonstrated that depleting IL-4Rα-expressing B cells in mb1creIL-4Rα-/lox mice considerably impaired the host ability to down-modulate granulomatous inflammation in the liver and gut during chronic schistosomiasis. Taken together, our findings indicate that within the B cell compartment, IL-4Rα-expressing B cells in particular down-modulate the deleterious egg-driven tissue granulomatous inflammation to enable host survival during schistosomiasis in mice.

Interleukin-4 receptor alpha is still required after Th2 polarization for the maintenance and the recall of protective immunity to Nematode infection.

There is currently no vaccine against parasitic nematodes and the knowledge on the mechanisms by which protective immunity against this class of parasites is achieved is continuously expanding. Nematode parasites trigger a host protective type 2 immune response via interleukin-4 receptor alpha (IL-4Rα). Despite this central role, it is not known whether IL-4Rα has a role in maintaining host type 2 immune responses following polarization. To determine the role of IL-4Rα after polarization, we used a recently established strain of rosaCreERT2-/+IL-4Rα-/Lox mice where il4rα gene deletion can be temporally controlled. We show that sustained expression of IL-4Rα is required for the maintenance of type 2 immune responses and protective immunity following interruption after polarization with Nippostrongylus brasiliensis primary infection. Moreover, we show by temporal deletion of IL-4Rα prior to secondary infection with N. brasiliensis that signaling via this receptor drives more efficient recall of type 2 immune responses and clearance of the parasites. Together, this study demonstrates that sustained IL-4Rα mediated signaling is required for the maintenance of anti-nematode type 2 immune responses, describing a novel function for IL-4Rα that is distinct from its role in immune polarization.

Protective immune responses against Schistosoma mansoni infection by immunization with functionally active gut-derived cysteine peptidases alone and in combination with glyceraldehyde 3-phosphate dehydrogenase.

BACKGROUND: Schistosomiasis, a severe disease caused by parasites of the genus Schistosoma, is prevalent in 74 countries, affecting more than 250 million people, particularly children. We have previously shown that the Schistosoma mansoni gut-derived cysteine peptidase, cathepsin B1 (SmCB1), administered without adjuvant, elicits protection (>60%) against challenge infection of S. mansoni or S. haematobium in outbred, CD-1 mice. Here we compare the immunogenicity and protective potential of another gut-derived cysteine peptidase, S. mansoni cathepsin L3 (SmCL3), alone, and in combination with SmCB1. We also examined whether protective responses could be boosted by including a third non-peptidase schistosome secreted molecule, glyceraldehyde 3-phosphate dehydrogenase (SG3PDH), with the two peptidases. METHODOLOGY/PRINCIPAL FINDINGS: While adjuvant-free SmCB1 and SmCL3 induced type 2 polarized responses in CD-1 outbred mice those elicited by SmCL3 were far weaker than those induced by SmCB1. Nevertheless, both cysteine peptidases evoked highly significant (P < 0.005) reduction in challenge worm burden (54-65%) as well as worm egg counts and viability. A combination of SmCL3 and SmCB1 did not induce significantly stronger immune responses or higher protection than that achieved using each peptidase alone. However, when the two peptidases were combined with SG3PDH the levels of protection against challenge S. mansoni infection reached 70-76% and were accompanied by highly significant (P < 0.005) decreases in worm egg counts and viability. Similarly, high levels of protection were achieved in hamsters immunized with the cysteine peptidase/SG3PDH-based vaccine. CONCLUSIONS/SIGNIFICANCE: Gut-derived cysteine peptidases are highly protective against schistosome challenge infection when administered subcutaneously without adjuvant to outbred CD-1 mice and hamsters, and can also act to enhance the efficacy of other schistosome antigens, such as SG3PDH. This cysteine peptidase-based vaccine should now be advanced to experiments in non-human primates and, if shown promise, progressed to Phase 1 safety trials in humans.

Ameliorating Role Exerted by Al-Hijamah in Autoimmune Diseases: Effect on Serum Autoantibodies and Inflammatory Mediators.

Autoimmune diseases have common properties characterized by abnormal blood chemistry with high serum autoimmune antibodies, and inflammatory mediators. Those causative pathological substances (CPS) cannot be excreted by physiological mechanisms. Current treatments for autoimmune diseases involve steroids, cytotoxic drugs, plasmapheresis and monoclonal antibodies. Wet cupping therapy (WCT) of prophetic medicine is called Al-hijamah that treats numerous diseases having different etiology and pathogenesis via a pressure-dependent and size-dependent non-specific filtration then excretion of CPS causing clearance of blood and interstitial fluids. Al-hijamah clears blood passing through the fenestrated skin capillaries. Medical bases of Al-hijamah were reported in the evidence-based Taibah mechanism (Taibah theory). Al-hijamah was reported to be an excellent treatment for rheumatoid arthritis that improved patients' blood chemistry and induced significant clinical improvement and pharmacological potentiation. Al-hijamah improved the natural immunity and suppressed the pathological immunity through decreasing the serum level of autoantibodies, inflammatory mediators, and serum ferritin (a key player in autoimmunity). Al-hijamah reduced significantly pain severity, number of swollen joints and disease activity with no significant side effects. Main steps of Al-hijamah are skin suction (cupping), scarification (sharatmihjam in Arabic) and second suction (triple S technique) that is better therapeutically than the traditional WCT (double S technique). Whenever an excess noxious substance is to be removed from patients' blood and interstitial fluids, Al-hijamah is indicated. Shartatmihjam is a curative treatment in prophetic teachings according to the prophetic hadeeth: "Cure is in three: in shartatmihjam, oral honey and cauterization. I do not recommend my nation to cauterize". Al-hijamah may have better therapeutic benefits than plasmapheresis. Al-hijamah may be promising in treating autoimmune diseases as a sole treatment or adjuvant treatment.

Evaluation of direct detection of Mycobacterium tuberculosis in clinical samples using the BD ProbeTec ET system.

OBJECTIVE: To evaluate the performance of the semi-automated BD ProbeTec ET system for the direct detection of Mycobacterium tuberculosis complex (MTBC) in comparison with microscopy, and culture for respiratory and non-respiratory specimens. METHODS: The study was conducted in the Maternity and Children's Hospital, Madina, Saudi Arabia from October 2008 to October 2009. A single center prospective study of 70 suspected tuberculosis samples were subjected to microscopy, culture (solid and liquid), and the DB ProbeTec ET system. RESULTS: A total of 70 specimens were studied; 47 respiratory, and 23 non-respiratory. Twelve (92.3%) ProbeTec positive results were obtained from 13 MTBC isolates from culture, while one specimen was BD ProbeTec ET positive, but yielded no growth on culture. Two samples gave anomalous results (false negative and positive results). The evaluated system showed sensitivity of 92.3%, specificity of 98%, positive predictive value of 92.3%, and negative predictive value of 98% for all specimens, while 88% sensitivity, 100% specificity, 100% positive predictive value, and 97.3% negative predictive value in cases of respiratory specimens, and 100% sensitivity, 93.3% specificity, 80% positive predictive value, and 100% negative predictive value in cases of non-respiratory specimens. CONCLUSION: The ProbeTec ET is a rapid and specific method for direct detection of MTBC in clinical specimens compared with the gold standard of culture, especially in patients with smear-negative non-respiratory specimens.

Induction of hepatitis C virus-specific cytotoxic T lymphocytes in mice by immunization with dendritic cells transduced with replication-defective recombinant adenovirus.

We studied the potential of dendritic cells (DCs) in priming hepatitis C virus (HCV)-specific cytotoxic T lymphocytes (CTLs) in mice. Recombinant adenovirus expressing HCV core (Adex1SR3ST) was employed to express core in DCs. Core-specific CTLs are effectively elicited by injecting Adex1SR3ST-transduced DCs, whereas injection of Adex1SR3ST does not result in effective priming. Further, Adex1SR3ST-transduced DCs more efficiently prime core-specific CTLs than Adex1SR3ST-transduced macrophages, or DCs treated with an anthrax toxin fusion protein reported previously. Upon challenge with recombinant HCV-core-expressing vaccinia virus, vaccinia titers are significantly reduced in mice immunized with Adex1SR3ST-transduced DCs. Thus, adenovirus-transduced DCs may be a promising candidate for a CTL-based vaccine against HCV.