effect of stem cells as an adjuvant on the immunogenicity of a potential anti-schistosomal vaccine in mice

Vaccination against schistosomes can be targeted towards the prevention of infection and/or to the reduction of parasite fecundity and pathology. However, as eggs are responsible mainly for schistosomiasis pathology, so crude soluble egg antigen [SEA] seems suitable to be used as a potential vaccine. Many studies have provided new insights establishing a role for mesenchymal stem cells [MSCs] in liver regeneration and improvement of schistosomiasis hepatic fibrosis, in addition to the need for standardized and effective adjuvant-vaccine formulations. So, the aim of this work is to evaluate the effect of stem cells when used as an adjuvant of a potential antischistosomal vaccine [crude SEA] in murine models. The current work was carried out on 100 mice [30 males for harvesting MSCs + 70 females for seven study groups, each of 10]. A schedule of vaccination and challenge infection was followed so, G1 [control healthy], G2 [control infected only] infected subcutaneously with S. mansoni cercaria [80-90 Schistosorna mansoni cercariae suspended in 0.2 ml distilled water], G3 [FCA then infected] received Freund's complete adjuvant [FCA] then infected, G4 [MSCs then infected] received MSCs then infected, 05 [SEA then infected] received SEA vaccine then infected, G6 [SEA+FCA then infected] received SEA vaccine and FCA then infected, 07 [SEA+MSCs then infected] received SEA vaccine and MSCs then infected. The current work was assessed by histopathological study and morphometric analysis [using H and E and Masson's Trichrome stains] to highlight number, size arid type of liver granulomas and percentage of liver fibrosis, immunological and molecular studies [RNA extraction, Reverse Transcriptase and PCR technique] for detection of interleukin-1 0 mRNA gene expression in liver tissue by reverse transcriptase and polymerase chain reaction [RT and PCR]. The results showed that a- SEA alone as a potential anti-schistosomal vaccine was more or less moderately protective, b- MSCs alone before the infection had mild prophylactic effects, c- MSCs as an adjuvant of the crude SEA increased its capabilities with highly significant results regarding the decrease in granuloma number, size, percentage and density of hepatic fibrosis, and d-There was significant increase in IL-10 mRNA gene expression on using [SEA+MSCs] [G7] if compared to other tested groups

Potential role of interleukin 4 and 12 as adjuvants to tegumental antigen in a vaccination model for murine Schistosomiasis mansoni

Vaccine strategies represent an essential component for the future control of schistosomiasis. A variety of vaccines from different Schistosoma stages and different adjuvants have been identified to induce a level of host protective immune response as a trial to decrease morbidity. This work aimed to evaluate IL4 and IL12 as adjuvant for Schistosoma mansoni tegumental antigens [TA] vaccines prior to challenge of infection by S. mansoni. Sodium dodecyl sulfate [SDS] was selected for extraction of tegumental proteins. Ten groups of BALB/c mice [7 mice in each group] were classified into 4 control groups G1: non infected non vaccinated; G2: infected only; G3: given IL4 and G4: given IL12. The other 6 groups included G5: vaccinated by TA in a dose of 40 ug; G6: vaccinated by TA in a dose of 55 ug; G7: vaccinated by TA dose 40 ug and 100 ug of IL4; G8: vaccinated by TA dose 55 ug and 100 ug of IL4; G9: vaccinated by TA dose 40 ug and 100 ug of IL12 and G10: vaccinated by TA dose 55 ug and 100 ug of IL12. Booster doses were given for all groups after 2 and 4 weeks. Two weeks after the last booster dose mice in all tested groups were infected by S. mansoni cercariae [100 cercariae/mouse] via tail immersion technique. Seven weeks post infection [PI], mice were sacrificed and parasitological parameters [worm burdens, liver and stool egg counts] were studied to evaluate the impact of this vaccination model. Histopathological studies by Haematoxylin and Eosin [HE] and Feulgen stains were also performed. The use of IL12 as an adjuvant to TA revealed a significant reduction in worm burden, liver egg count and decreased ova count in stools as compared to their corresponding controls. In addition, histopathological examination of liver sections in the tested groups given IL12 showed decrease in the size and number of granuloma with decrease of liver cell apoptosis. On the other hand, both parasitological and histopathological results of the tested groups given to IL4 as an adjuvant to TA were contradictory. IL 12 potentiated the protective effect of S. mansoni tegumental antigen vaccine and posed as a useful adjuvant, while IL4 was less effective. TA is an efficient model for future studies in molecular identification of novel candidate tegumental proteins

Risk factors of a soil mediated helminthiasis: Toxocariasis among children [aged 4-16 years]

The present study was carried out to determine the seroprevalence and underlying risk factors of toxocariasis in Sharkia Governorate. A group of 828 [age ranged from 4 to 16 years] was selected by systematic random sampling, from rural and urban areas. Infection was serologically diagnosed by ELISA technique.Seropositive cases were found representing 153% of the whole sample, 20.6% of males versus 10.7% of females were seropositive and 18.7% of those living in rural areas compared to 11.7% in urban areas. The relationship between seroprevalence and host factors including age, sex, residence, socio-economic standard and risk factors as pet contact, geophagia and thumbsucking were explored. Eosinophilia was found as a characteristic highly significante sign related to toxocariasis in children. Logestic regression analysis revealed that the most influencing factors on seropositivity of toxocariasis were pet contact [Odds ratio = 4.6] followed by thumbsucking [Odds ratio = 3.54]. The geophagia, eosinophilia and host age "younger" were also found to add significantly to the model. So, the recognition of toxocariasis risk factors is the key for prevention and control

Some parasitic diseases as a cause of rheumatic pains

It was found that some parasitic diseases could precipitate a wide complaint of rheumatic like pains. So, one hundred cases were chosen, among the patients who presented to the Outpatient Clinics of Rheumatology and Rehabilitation Department at Zagazig University Hospitals, [complaining of chronic, recurrent rheumatic pains, not responding to the usual non-steroidal antirheumatic treatment. They aged 25 - 50 years, of both sexes and from rural and urban areas. Full history taking, thorough physical and clinical examinations and complete laboratory investigations were done to: exclude other causes of rheumatic pains, diagnose and confirm the parasitic infections [using stool and urine analysis then IHAT]. 24% were found suffering from parasitic infections: 6 cases[6%] schistosomiasis, 4 amaebiasis [4%], 3 Toxoplasma infection [3%] and 2 toxocariasis [2%],3 cases had mixed parasitic infection [3%] 2 cases schistosomiasis and amaebiasis, 1 case shistosomiasis and toxoplasmosis], 6 cases [6%] were suffering from parasitic infection in addition to other cause of rheumatic pains. No significant difference were found among these different groups, regarding age, sex and residence.The usual clinical parasitic manifestations of dysentery diarrhoea, nausea'etc., were good criteria to evoke the diagnosis. Considering the erythrocyte sedimentation rate [E.S.R.] readings, a significant difference was found among schistosomal arthropathy group and other parasitic groups, that showed unsignificant differences.The clinical picture of arthritis induced by parasitic infections was non specific because it was usually accompanied by myalgia, sometimes knee joint effusion, as the clinical picture of different inflammatory rheumatic diseases.The role of Immune Complex [IC] in the pathogenesis of parasitic arthropathy, myopathy and joint effusion was discussed, on basis of the results of specific IC level estimation by micro-ELISA in the sera of the cases harbouring parasitic infections and synovial fluids [in cases with joint effusion], and compared with the results control group, a highly significant elevation was recorded in toxocariasis, significant rises reported in schistosomiasis and amaebiasis and a moderately significant increase noticed in toxoplasmosis. Also, IC was highly elevated in the synovial fluids above serum levels in cases of schistosomiasis, toxoplasmosis and toxocariasis with knee joint effusion, suggesting a secondary local immunological reactions. Therefore, it can be concluded that rheumatic like pains, related to some parasitic infections in our country as schistosomiasis, amaebiasis, toxoplasmosis and toxocariasis were due to immunological reactions, that IC, either in the serum or in the synovial fluid plays the major role, with probable minor roles played by excretory toxic metabolites of some parasites, others may cause limited direct catabolic effects in the joints and muscles. Thus, these parasitic infections as aetiological causes of chronic, and recurrent rheumatic - like pains should be considered wider than previously thought

Acanthamoeba keratitis

The role of Acanthamoeba species in causing keratitis is increasingly recognized, that in this study 9 cases out of 28 cases [32.1%] of resistant keratitis were investigated and proved having Acanthamoeba keratitis. This high rate was discussed on clinical and laboratory basis. The cases were presenting to the Ophthalmology Clinic of Zagazig University Hospital. Thorough ophthalmological examination and accurate parasitological investigations including: culturing of the corneal isolates on non nutrient agar and microscopic examination of direct, wet and unstained smears, also doing flagellation test, were performed These methods revealed and confirmed the presence of trophozoite, precyst and cyst stages of Acanthamoeba in nine corneal scrapings.The cases were 7 males and 2 females, aged from 35-75 years, eight from rural areas and one from urban area. The major predisposing risk factor was contaminated minor eye trauma [44.4%] followed by foreign body [22.2%], while contact lens wear, contamination of the eye by sewage and unrecognized cause showed minor roles as risk factors. Regarding the clinical presentations of Acanthamoeba keratitis, the symptoms [ocular discomfort, photophobia, lacrimation.. etc] were non specific and simulated those of most corneal infections, while the signs, 2 cases [22.2%] showed anterior stromal keratitis, in the form of ring infiltration of the stroma, 3 cases [33.3%] showed central corneal haze with a fine granular appearance, 3 cases [33.3%] showed extensive and deep stromal infiltrates and an extensive corneal abscess with superficial ulceration were recorded in one case. Therefore, amoebic keratitis should be considered in the differential diagnosis of resistant keratitis especially those not responding to treatment for long duration, combined with a suggestive history [risk factors especially eye trauma]. So, cultures for Acanthamoeba should be routinely done for all cases of keratitis, for early diagnosis, as detection of Acanthamoeba species in corneal scrapings provides the main diagnostic feature

Water as a source of cryptosporidial infection among patients with diarrhea in El-Ekhewa village-El Sharkiya governorate

Water samples were collected from five sources related to five residential areas where human populations use them in their daily life and for drinking in El-Ekhewa village. The first and the second were slow running surface water, the third was underground water at shallow depth [5.6 +/- 18 meters], the fourth was chlorinated piped water and the fifth was underground water at depth> [21 +/- 1] meters. The samples were filtered, diluted then concentrated. The thick walled oocysts of Cryptosporidium were identified and counted after specific monoclonal immunofluorescent staining. The density of water contamination by thick walled oocysts per litre was high in surface water of the first [465] and the second [398] sources: Both are frequently in contact with domestic and wild animals. Lesser degrees, although still infective were encountered in underground water at shallow depth [132] and in the piped chlorinated water [85]. Meanwhile, no oocysts were detected in the underground water at depth>20 meters. These findings may indicate that the oocyts are chlorine resistant and the main method for their elimination is effective filteration. Stool from 120 patients with diarrhea and 100 without diarrhea [1-20 ys] from these 5 areas were examined by acid fast trichrome stain of saline Hemo De concentrate to detect intestinal parasites including coccidia and microsporida Bacterial pathogens were sought by standard bacteriologic techniques. Only those with Cryptosporidium as single pathogen were considered. 10.4% of the symptomatic were shedding oocysts in their stools.The correlation between the density of water contamination and the prevalence of cryptosporidiosis among individuals of each area was so significant that it can be concluded that the disease in the present community is water borne. Most of symptomatic cases were encountered at mean age [10.6/-4.2] while the asymptomatic cases were mostly detected at mean age [15 7 +/- 4.4] indicating age related tolerance towards this organism

Fascioliasis as an aetiologie case of fever of unknown origin [FUO] among children [4-12 years] old

Idiopathic fever represents a diagnostic dilemma in small age group. Little attention was given as regard parasitic infections and fever of unknown origin [FUO]. The objective of this study was to throw some light upon the role of fascioliasis as a cause of fever of unknown origin. The study revealed fascioliasis by stool analysis in 14 cases out of children [4.3%] presenting by undiagnosed and prolonged fever and their ages [4-12 years]. Dot- ELISA enabled us to discover 20 cases out of those 320 patients [6.25%], the difference between the results obtained by stool analysis and dot-ELlSA is not significant. Fever [38 drgree] was prolonged and was complained by all the Fasciola seropositive cases by dot-ELISA i.e. 20 cases [100%], eosinophilia in high counts was reported in most of the cases, it is a characteristic of fascioliasis. Hepatobiliary disorders and weight loss were recorded in 60% of the seropositive cases. The scleral tinge of jaundice was noticed in 40% of cases, while diarrhoea, liver enlargement and abdominal pains were reported in 20% of feverish children. Vomiting was complained only by 10% of cases. So Fasciola infection should be considered as one of the aetiological causes of fever of unknown origin [FUO] [6.25%] in children [4-12 years]. Fascioliasis in children usually presented by fever and eosinophilia. Dot- ELISA is an important tool for Fasciola diagnosis, besides the stool examination techniques. Young- aged male children suffered from fascioliasis as a cause of fever of unknown origin more than female children

Detection of free living amoeba in five aquatic sites in Sharkia governorate

Detection of free living amoebae [FLA] in fresh water canals and drains, as a possible cause of primary amoebic meningo-encephalitis [PAM], was carried out of Sharkiya Governorate. So fifty surface water samples from different 5 aquatic sites were studied. On cultivation: eleven of them were containing FLA, representing 22%. Naegleria spp. and Acanthamoebae spp. were isolated and identified on morphological basis and flagellation test. The two strains were investigated in the water of polluted drains. Three groups of mice were used to perform the pathogenicity test, one as a control, another tested by Naegleria spp. and the third was tested by Acanthamoeba spp. None of the mice died during the test time [15 days], but some histopathological differences were noticed in the brain sections, however no signs or symptoms of meningitis were recorded in the tested mice. It could be concluded that the isolated and intranasal inoculated free living amoebae strains in this work were non pathogenic to mice, but this cannot deny their possible role in causing PAM in man

Humoral and cellular immune responses in experimental trichinosis

This work was designed to study the relation between cellular and humoral immune responses in experimentally infected albino rats with T. spiralis larvae over a period of four weeks. Cell-mediated immune response [measured by lymphoblast transformation test] revealed a marked lymphoblast response during the intestinal phase, but the reaction became irregular with larval encystation in muscles. Humoral immune response was estimated by both of micro- and dot-ELISA techniques. It was obvious that significant higher OD readings and dot color intensities were observed in the muscular phase than in intestinal phase. The results proved that micro-ELISA had the least accuracy [66.6%] and poorest specificity [81.25%], while dot-ELISA showed the best sensitivity [100%] and highest specificity [87.5%]. Lymphoblast transformation was as specific as dot-ELISA

Histochemical studies in experimental trichinosis

The study of the behaviors of Trichinella spiralis in the host tissues from the histochemical point of view will throw a light on parallelism of the destruction process by the infection and the instruction of the host tissues, i.e., the catabolic effect of the parasite as an indicator of the severity of infection and the anabolic response by the host as a criteria of cure. So, this study revealed a definite increase in catabolic enzymes as acid phosphatase activities. A relative disturbance and a decrease of anabolic enzymes [succinate dehydrogenase, alkaline phosphatase, non-specific esterase and adenosine triphosphatase [ATPase] reactivity which indicates the destructive effects of T. spiralis adult worms and encysted larvae on intestinal mucosa a striated muscles of tongue and diaphragm. The disturbances of anabolic enzymes activity revealed the continuous trials of the host to get rid of adult worms from the small intestine, and to defeat and isolate the larvae in striated muscles. While the renal tissue changes indicate the disturbance of absorption and excretion functions of renal tissue due to the presence of endmetabolites and products of the parasite in the host blood

Effect of immune suppression on intestinal mastocytosis in experimental trichinosis

The present study showed that experimental Trichinella infection of rats resulted in marked mucosal mast cell hyperplasia among infected non-treated and Endoxan treated rats in comparison to non infected and hydrocortisone treated rats who showed non significant mucosal mast cell alteration. The present finding supports the view that the precursors of mucosal mast cells involved in Trichinella expulsion are T-lymphocyte dependent and be inhibited by cortisone therapy and not by cyclo- phosphamide