Pyroptosis Tuning in Intestinal Cryptosporidiosis via the Natural Histone Deacetylase Inhibitor Romidepsin.

Cryptosporidium is an opportunistic protozoan, with many species of cross-human infectivity. It causes life-threatening diarrhoea in children and CD4-defective patients. Despite its limited efficacy, nitazoxanide remains the primary anti-cryptosporidial drug. Cryptosporidium infects the intestinal brush border (intracellular-extracytoplasmic) and down-regulates pyroptosis to prevent expulsion. Romidepsin is a natural histone deacetylase inhibitor that triggers pyroptosis. Romidepsin's effect on cryptosporidiosis was assessed in immunocompromised mice via gasdermin-D (GSDM-D) immunohistochemical expression, IFN-γ, IL-1ß and IL-18 blood levels by ELISA, and via parasite scanning by modified Ziehl-Neelsen staining and scanning electron microscopy (SEM). Oocyst deformity and local cytokines were also assessed in ex vivo ileal explants. Following intraperitoneal injection of romidepsin, oocyst shedding significantly reduced at the 9th, 12th and 15th d.p.i. compared with infected-control and drug-control (nitazoxanide-treated) mice. H&E staining of intestinal sections from romidepsin-treated mice showed significantly low intestinal scoring with marked reduction in epithelial hyperplasia, villous blunting and cellular infiltrate. SEM revealed marked oocyst blebbing and paucity (in vivo and ex vivo) after romidepsin compared with nitazoxanide. Regarding pyroptosis, romidepsin triggered significantly higher intestinal GSDM-D expression in vivo, and higher serum/culture IFN-γ, IL-1ß and IL-18 levels in romidepsin-treated mice than in the control groups. Collectively, in cryptosporidiosis, romidepsin succeeded in enhancing pyroptosis in the oocysts and infected epithelium, reducing infection and shifting the brush border towards normalisation.

Potential i-Nos/Arg-1 Switch with NLRP3 and Parasitic Load Down Regulation in Experimental Schistosoma mansoni Infection via Chloroquine Repurposing.

In previous studies, the inhibitory effect of chloroquine on NLRP3 inflammasome and heme production was documented. This may be employed as a double-bladed sword in schistosomiasis (anti-inflammatory and parasiticidal). In this study, chloroquine's impact on schistosomiasis mansoni was investigated. The parasitic load (worm/egg counts and reproductive capacity index [RCI]), i-Nos/Arg-1 expression, splenomegaly, hepatic insult and NLRP3-immunohistochemical expression were assessed in infected mice after receiving early and late repeated doses of chloroquine alone or dually with praziquantel. By early treatment, the least RCI was reported in dually treated mice (41.48 ± 28.58) with a significant reduction in worm/egg counts (3.50 ± 1.29/2550 ± 479.58), compared with either drug alone. A marked reduction in the splenic index was achieved by prolonged chloroquine administration (alone: 43.15 ± 5.67, dually: 36.03 ± 5.27), with significantly less fibrosis (15 ± 3.37, 14.25 ± 2.22) than after praziquantel alone (20.5 ± 2.65). Regarding inflammation, despite the praziquantel-induced significant decrease in NLRP3 expression, the inhibitory effect was marked after dual and chloroquine administration (liver: 3.13 ± 1.21/3.45 ± 1.23, spleen: 5.7 ± 1.6/4.63 ± 2.41). i-Nos RNA peaked with early/late chloroquine administration (liver: 68.53 ± 1.8/57.78 ± 7.14, spleen: 63.22 ± 2.06/62.5 ± 3.05). High i-Nos echoed with a parasiticidal and hepatoprotective effect and may indicate macrophage-1 polarisation. On the flip side, the chloroquine-induced low Arg-1 seemed to abate immune tolerance and probably macrophage-2 polarisation. Collectively, chloroquine synergised the praziquantel-schistosomicidal effect and minimised tissue inflammation, splenomegaly and hepatic fibrosis.

Niosomal versus nano-crystalline ivermectin against different stages of Trichinella spiralis infection in mice.

Ivermectin (IVM) is one of the competitive treatments used for trichinellosis. However, several studies linked its efficacy with early diagnosis and administration to tackle the intestinal phase with limited activity being recorded against encysted larvae. The aim of this study was to employ niosomes for enhancing effectiveness of oral IVM against different stages of Trichinella spiralis (T. spiralis) infection with reference to nano-crystalline IVM. Mice were randomized into four groups: group Ι, 15 uninfected controls; group ΙΙ, 30 infected untreated controls; group ΙΙΙ, 30 infected nano-crystalline IVM treated, and group ΙV, 30 infected niosomal IVM treated. All groups were equally subdivided into 3 subgroups; (a) treated on the 1st day post infection (dpi), (b) treated on the 10th dpi, and (c) treated on the 30th dpi. Assessment was done by counting adult worms and larvae plus histopathological examination of jejunum and diaphragm. Biochemical assessment of oxidant/antioxidant status, angiogenic, and inflammatory biomarkers in intestinal and muscle tissues was also performed. Both niosomes and nano-crystals resulted in significant reduction in adult and larval counts compared to the infected untreated control with superior activity of niosomal IVM. The superiority of niosomes was expressed further by reduction of inflammation in both jejunal and muscle homogenates. Biochemical parameters showed highly significant differences in all treated mice compared to infected untreated control at different stages with highly significant effect of niosomal IVM. In conclusion, niosomal IVM efficacy exceeded the nano-crystalline IVM in treatment of different phases of trichinellosis.

Bevacizumab as a potential anti-angiogenic therapy in schistosomiasis: A double-edged, but adjustable weapon.

AIM: Investigating the anti-angiogenic effect of bevacizumab on chronic schistosomiasis mansoni in a trial to hinder the Schistosome-induced angiogenesis and porto-systemic shunting complications. METHODS: The immunohistochemical expression of CD34, VEGF-R1, PCNA and α-SMA (angiogenesis markers) was analysed in the lung, liver and gastrointestinal junctions of chronic S mansoni infected mice after intraperitoneal injection of bevacizumab. The effect of prolonged administration of bevacizumab with praziquantel was also assessed through parasitic load, protective index, granuloma and fibrous tissue evaluation. RESULTS: A regression in the vascular activity and microvascular density was observed in the infected mice after receiving bevacizumab. They had a significantly less VEGF-R1, PCNA, CD-34 and α-SMA expression in comparison to the infected untreated mice. The least tissue egg count was reported in mice received bevacizumab for 6 weeks (Mean = 27 120). However, they had persistent liver granulomas, and massively amalgamated fibrosis. Interestingly, the least faecal egg and tissue worms counts (Mean = 112, 13.4), and the highest protection index (39.26) were reported in mice received bevacizumab for 3 weeks, with marked granuloma, and fibrous tissue resolution. CONCLUSIONS: Bevacizumab has a promising protective effect against the Schistosoma-induced angiogenesis. As an adjuvant to praziquantel, it is important to adjust the appropriate duration of administration that achieves the best schistosomicidal effect without impeding granuloma and fibrous tissue resolution.

Acidic mammalian chitinase tuning after enteric helminths eradication in inflammatory respiratory disease patients.

AIM: This study aimed at investigating the presence of intestinal parasitic infections in inflammatory respiratory diseases patients during the disease attack, and measuring the acidic mammalian chitinase (AMCase) gene expression in blood before and after infection eradication. METHODOLOGY: This case-control study included 123 inflammatory respiratory diseases patients and 120 apparently healthy individuals. Repeated stool examination was done, while total and specific IgE were measured. AMCase gene expression was analysed by real time-polymerase chain reaction (RT-PCR). RESULTS: Infection was detected in 32.5% of the diseased and 23.25% of the healthy individuals. Higher rate of the helminthic infection was detected (23.57) in comparison to the protozoal (12.19%) in the patients. A significantly higher rate of infection with the chitin-rich helminths "Enterobius vermicularis & Hymenolepis nana" and level of anti-Dermatophagoide-IgE were reported in the patients (14.63%, 6.5% and 23.57%, respectively). AMCase expression was significantly higher in helminths-infected patients than the noninfected, or protozoa infected. After infection eradication, AMCase expression significantly declined in the previously helminth-infected patients (mean ± SD = 13.9 ± 3.918 before and 4.515 ± 1.93 after), but insignificantly affected in the protozoa infected (mean ± SD = 2.095 ± .285 before and 2.675 ± 1.181 after). CONCLUSION: Chitin-rich intestinal helminths are suspected to precipitate Th2-immune response in remote tissues by enhancing systemic AMCase expression through intestinal mucosa and macrophages irritation.

Biofilm testing of microbiota: An essential step during corneal scrap examination in Egyptian acanthamoebic keratitis cases.

PURPOSE: To detect co-infections in the culture-proven acanthamoebic keratitis (AK) cases, and to test the capability of biofilm formation in the isolated microbiota. The clinical findings, habit of wearing contact lens and in-vitro antibiotic resistance were analyzed further according to the biofilm formation capability. METHODS: After clinical examination, corneal scraps and swabs were taken from 240 clinically suspected AK cases, for Acanthamoeba and microbiological cultures. In cases of keratoplasty, trimmed corneal tissue was collected and sent for histopathological examination. Scanning electron microscopy was done for some samples. Biofilm formation capability was investigated using a tissue culture plate method. Antibiotic resistance pattern was determined using a modified-Kirby-Bauer disc diffusion method. RESULTS: In 102 AK culture proven cases, 11 had no co-infection, 74 had a single co-infection and 17 had double co-infections. Enterobactericae and Aspergillus were the commonest bacterial and fungal isolates, respectively. Regarding the biofilm formation, 64.7% of Enterobactericae, 50% of Pseudomonas aeuroginosa, 43.75% of Staph aureus, 76.92% of Streptococcus pneumoniae, 28.57% of Corynebacterium, 60% of α-haemolytic streptococci, 40% of Acinetobacter, 100% of Candida and 77.8% Aspergillus isolates were biofilm producers. Severe manifestations were more frequently reported in cases co-infected with biofilm producers than with non-biofilm producers. Generally, high percentages of the biofilm forming bacterial isolates were sensitive to antibiotics in-vitro. CONCLUSIONS: Routine investigations for co-infection and biofilm formation in addition to Acanthamoeba culture are strongly recommended in suspected AK cases. Co-infection with biofilm producers may precipitate extrinsic in-vivo drug resistance despite of the in-vitro sensitivity. Designing a biofilm-dissolving topical drug is highly recommended to enhance the response to the standard therapeutic regimen especially in the resistant AK cases.

Trichinella Spiralis Impact on Mesenchymal Stem Cells: Immunohistochemical Study by Image Analyzer in Murine Model.

This study aims to elucidate whether Trichinella spiralis infection or its crude antigen administration can stimulate recruitment of CD105+ve/CD45-ve cells that could represent MSCs in intestine and skeletal muscle of experimental BALB/c albino mice compared to healthy control mice. Studied mice were divided into: 20 healthy control, 20 with orally induced T. spiralis infection, 20 received adult worm crude antigen orally and 20 received larval crude antigen intramuscular. According to specific timing schedule, mice were sacrificed and tissue sections were examined for CD105 and CD45 immunohistochemical expression using image J image analyzing software, to compare different study groups. T. spiralis infection induced a significant increase in density of CD105+ve/CD45-ve cells that could represent MSCs in both intestinal and muscle sections, similarly the intramuscular injected larval crude antigen caused more infiltration of such cells in muscles compared to muscle sections from healthy control mice. However, no significant difference was noticed in intestinal sections after oral adult crude antigen administration compared to healthy control mice. So, injected T. spiralis crude antigen might be a successful stimulant to MSCs attraction and recruitment in tissues nearby injection site. This could be beneficial for cell regeneration and tissue repair in case of presence of a disease induced damage.

FoxP3+ T regulatory cells and immunomodulation after Schistosoma mansoni egg antigen immunization in experimental model of inflammatory bowel disease.

To assess the effect of Schistosoma mansoni egg antigen immunization on the immunomodulation in dextran sodium sulfate (DSS) induced colitis as an experimental model of IBD in comparison to non immunization and healthy control. The study was performed on 180 mice; 25 healthy control, 15 to identify the inflammatory peak of DSS, 25 received DSS for 7 days; 90 infected with S. mansoni cercariae to collect eggs for antigen preparation, and 25 immunized with the prepared antigen then received DSS course. Disease activity index, macroscopic & microscopic inflammatory scores, FoxP3+ T regulatory cell count, myeloperoxidase activity, and Th1/Th2 cytokine profile were compared in studied groups. Immunization induced both FoxP3+ T(regs) and Th2 cytokines to establish a state of immune homeostasis and create a quiescent steadier immune response to DSS. S. mansoni egg antigen succeeded in acting like a prophylactic helminthic therapy as it has a profitable modulatory effect on DSS-induced colitis model.