The effect of single dose versus two doses of praziquantel on Schistosoma haematobium infection and pathology among school-aged children in Mali.

The aim of this study was to assess the effect of two doses of 40 mg/kg praziquantel with 2 weeks interval versus a standard single dose of 40 mg/kg on cure rates, egg reduction, intensity of infection, and micro-haematuria in Schistosoma haematobium infections. A randomised controlled intervention study was carried out among school-aged children in two different endemic settings with follow-up at 3, 6 and 18 months following drug administration. Differences in cure rates between the two treatment regimens were not significant. However, in high transmission areas, the double treatment regimen was more effective in egg reduction than single treatment regimen and the difference in egg reduction between the two treatments was significant at 3 months (P<0.005), 6 months (P<0.0001) and 18 months (P<0.003) after treatment. There was a significant difference in the effect of the two treatments on prevalence of micro-haematuria at 18-month follow-up in both Koulikoro (P<0.001) and Selingue (P<0.003). The study shows that although no significant difference could be observed in the overall cure-rates between the two treatment regimens, the effect of double treatment was a significant reduction in infection intensity as well as micro-haematuria which may have a great impact in reducing subtle morbidity.

Circulating fibrosis markers, eosinophil cationic protein and eosinophil protein X in patients with Wuchereria bancrofti infection: association with clinical status.

We measured the concentrations of several circulating fibrosis markers (type I collagen I, type III procollagen, hyaluronan) and eosinophil granule proteins (ECP and EPX) in lymphatic filariosis patients to investigate their relationship with clinical, parasitological and immunological data. This study was conducted in Polynesian patients with various stages of the disease (acute lymphangitis, chyluria, hydrocoele, elephantiasis), a closely related microbial lymphangitis and endemic controls. We observed modifications of the different markers in this pathology. Serum type I collagen and PIIINP were decreased. Serum hyaluronan, linked to perilymphatic granulomatous inflammation, was significantly increased in acute lymphangitis and elephantiasis patients. Serum ECP was also increased, at the limit of significance in our sample, in elephantiasis patients. These two last markers, already validated in another helminth disease, schistosomiasis, have potential interest in terms of follow-up of morbidity in these parasitic diseases.

Detection of eosinophil cationic protein (ECP) by an enzyme-linked immunosorbent assay.

Eosinophil cationic protein (ECP) is a highly basic and potent cytotoxic single-chain zinc-containing protein present in the granules of the eosinophilic granulocytes. ECP appears to be involved in defence against parasites and in the tissue damage seen in subjects with allergic and inflammatory disease. To investigate ECP release from in vitro activated human eosinophils and to study the involvement of eosinophils in health and disease, we have developed a sensitive and specific enzyme immunoassay. ECP was purified from normal human peripheral blood eosinophils and polyclonal antibodies to ECP were subsequently raised in rabbits. The ELISA utilizes the biotin/avidin method and measures ECP within the range 15-1000 ng/l. The intra- and interassay coefficients of variation were 6% and 10%, respectively, and the recoveries of 12 and 25 pg of purified ECP added to diluted serum samples were 108 +/- 14.5% (mean +/- SD, n = 12) and 107 +/- 7.5%, respectively. The high sensitivity, reproducibility and specificity of this ELISA makes it suitable for the determination of minute amounts of ECP in in vitro systems as well as in various biological fluids.

Eosinophil protein X/eosinophil derived neurotoxin (EPX/EDN). Detection by enzyme-linked immunosorbent assay and purification from normal human urine.

Eosinophil protein X/eosinophil derived neurotoxin (EPX/EDN) is one of the cationic proteins found in the granules of the human eosinophilic granulocytes. EPX was purified from extracts of granules isolated from blood buffy coat cells of healthy donors. Polyclonal anti-EPX antibodies were subsequently raised in rabbits. The anti-EPX-antibodies raised in rabbits showed no reactivity with other proteins in the granule extract. The sandwich ELISA utilized the biotin/avidin amplification system and measured EPX over the range of 60-2000 pg/ml. The intra- and interassay coefficients of variation were 6.5% and 8.2%, respectively, and the mean recoveries of 25 and 50 pg of purified EPX added to diluted serum samples were 106 +/- 16% (mean +/- SD; n = 12) and 112 +/- 14%, respectively. Using this assay we found high amounts of EPX in normal human urine (U-EPX). U-EPX was purified by a two step procedure involving affinity chromatography on heparin Sepharose and size exclusion chromatography on Sephadex G-50 superfine. Extracted EPX and U-EPX had ribonuclease activity and comigrated on agarose electrophoresis. They also showed immunological identity when evaluated with rabbit anti-EPX antibodies, but they differed slightly on SDS-PAGE probably due to differences in glycosylation. Our results support the findings that EPX/EDN is identical to a nonsecretory ribonuclease isolated from urine.

A method for production and determination of histamine releasing activity from human peripheral blood mononuclear cells.

Histamine releasing factors, i.e. cytokines capable of inducing histamine release from basophils or mast cells, have been suggested to be involved in the pathogenesis of, for example, allergic late-phase reactions. Here we describe a controlled method for production and determination of histamine releasing activity (HRA) from human peripheral blood mononuclear cells (MNC). MNC were incubated with concanavalin A (Con A) for 2 h and cultured for another 40 h in fresh serum free medium. The culture supernatants were concentrated 19-25 fold by ultrafiltration (molecular weight cut-off: 3000 Da). The preparations of HRA induced dose- and Ca2+-dependent histamine release from leukocytes. Supernatants of parallel cultures of unstimulated MNC did not induce histamine release. The HRA was neither due to exogenous histamine releasing compounds (e.g. Con A) nor to residual histamine in the preparations of HRA. The kinetics of HRA induced histamine release (half-maximal release after > 40 min) were slower and more protracted than those of anti-IgE induced histamine release. However, based on a comparison between HRA induced histamine release from leukocytes and purified (97%) basophils, this did not appear to be due to an indirect effect on the basophils. Finally, neither the production of nor the response to HRA was dependent on the allergic status of the donor.

Measurement of eosinophil cationic protein (ECP) and eosinophil protein X/eosinophil derived neurotoxin (EPX/EDN). Time and temperature dependent spontaneous release in vitro demands standardized sample processing.

The measurement of eosinophil derived proteins such as eosinophil cationic protein (ECP) and eosinophil protein X/eosinophil derived neurotoxin (EPX/EDN) in biological fluids may be a useful indicator of eosinophil activity in ongoing inflammatory processes. This study was performed on blood samples and illustrates that serum values of ECP in particular, but also of EPX, are mainly a result of spontaneous release during the processing of blood samples. In the presence of divalent cations (Ca2+ and Mg2+), the amount of released ECP and EPX is dependent upon the incubation temperature and the time before centrifugation and recovery of serum. Moreover, the utensils used for blood sampling may influence the serum levels of ECP and EPX. Thus, standardized sample processing is of paramount importance if the results are to have optimal diagnostic or clinical value.

Reduced cellular immune reactivity in healthy individuals during the malaria transmission season.

Antigen-induced cellular immune responses are suppressed during acute malaria. The present study engages the possibility that malaria-induced alterations in cellular immune reactivity extend beyond the clinical disease. Thus, lymphoproliferative responses of healthy individuals were diminished during the malaria transmission period in individuals living in an area of highly seasonal, unstable malaria transmission. This finding may have important implications for the design of studies of stimulatory properties of antigens using lymphocytes of endemic origin.

Eosinophil cationic protein and eosinophil protein X: human amniotic fluid concentrations and gestational tissue content at term.

The aim of this study was to determine the presence and concentration of immunoreactive eosinophil cationic protein (ECP) and eosinophil protein X (EPX) in human amniotic fluid at term and assess labour-associated changes in their mean concentrations. In addition, ECP and EPX content in term amnion, choriodecidua and placenta obtained before and after labour and delivery was established. Immunoreactive ECP and EPX were identified in all samples of amniotic fluid (n=47) and gestational tissue (n=60) assayed. EPX was quantitatively more abundant than ECP in both amniotic fluid and gestational tissues. In amniotic fluid, ECP and EPX concentrations increased 8-fold (P<0.02) and 1.5-fold (P<0.02), respectively, with labour onset. In gestational tissues, a labour-associated change in tissue content was only identified for ECP in choriodecidua, which increased 1.9-fold with labour and delivery (P<0.01). The labour-associated increase in amniotic fluid concentrations of ECP and EPX demonstrated in this study is consistent with the well-characterized role of these proteins in inflammatory reactions. It remains to be established whether the observed increase in ECP and EPX amniotic fluid concentrations is an epiphenomenon of labour onset or is involved causally in this process.

Quantitative assessment of eosinophiluria in Schistosoma haematobium infections: a new marker of infection and bladder morbidity.

Eosinophiluria, as quantified by measuring eosinophil cationic protein (ECP) in urinary extracts, microhematuria, egg excretion, and ultrasound-detectable bladder pathology were recorded in Schistosoma haematobium-infected Tanzanian school children at a baseline survey and during an 18-month post-treatment follow-up study. Significant correlations were seen between urinary ECP levels, intensity of infection, and bladder pathology. Treatment resulted in a marked reduction in prevalence and intensity of infection, in a delayed and less marked reduction in ECP levels, and in a resolution of pathology. The overall diagnostic efficiency of the ECP test (cut-off value for the ECP > or =5 ng/ml) in relation to infection was comparable with that of egg count and microhematuria, but with a better sensitivity than a single egg count. In relation to bladder pathology, the diagnostic performance of the ECP test (cut-off value for the ECP > or =25 ng/ml) exceeded that of a single egg count. In addition, the ECP was better in discriminating between different grades of bladder pathology. The present study points to the ECP as a useful marker of both S. haematobium infection and of associated bladder morbidity reflecting the inflammatory status of the bladder wall.

Plasma protein leakage and local secretion of proteins assessed in sputum in asthma and COPD. The effect of inhaled corticosteroids.

Asthma and chronic obstructive pulmonary disease (COPD) are characterized by chronic airway inflammation with cell infiltration, increased plasma exudation and abnormal local secretion of proteins. We have analysed whether sputum differs in this respect between asthma (n = 9) and COPD (n = 9), and whether inflammatory markers in sputum are affected by treatment. In non-smoking asthma patients there was more plasma protein leakage, based on the relative coefficient of excretion Q alpha 2macroglobulin/QIgG (P = 0.03). There was less local secretion of sIgA and lactoferrin than in COPD (P < 0.05). Tryptase was slightly higher in sputum from asthma than from COPD (P < 0.05), whereas eosinophil cationic protein and myeloperoxidase were similar. After treatment with glucocorticosteroids, there was a reduction in the Q alpha 2macroglobulin/Qalbumin (P < 0.015), but no effect was seen on the levels of products from local cells. We conclude that sputum analysis is useful to study the local inflammatory process in asthma and COPD.

Assessment of morbidity in Schistosoma haematobium infection: current methods and future tools.

Recently, new potential tools for assessment of Schistosoma haematobium related morbidity have emerged. The tools are based on detection of S. haematobium egg antigens in urine or detection of eosinophil cationic protein (ECP) in urine, which may reflect the inflammatory response in the urinary tract. So far two markers have been assessed in long-term post treatment follow-up studies, allowing for an evaluation both before treatment and during regression and reappearance of infection and urinary tract morbidity. The results from these studies and the usefulness of the markers as morbidity assessment tools are discussed.

Indirect assessment of eosinophiluria in urinary schistosomiasis using eosinophil cationic protein (ECP) and eosinophil protein X (EPX).

The pre- and post-treatment level of eosinophiluria, as measured indirectly by the amount of free or cell bound eosinophil cationic protein (ECP) and eosinophil protein X (EPX) in urine from Schistosoma haematobium-infected Kenyan school children, were measured and compared with intensity of infection (eggs/10 ml of urine), albuminuria and pathological changes as detected by ultrasonography. ECP and EPX were determined by means of specific ELISA methods and levels were determined in both urine supernatants and extracted urine deposits (cells and cell debris). The level of ECP was significantly raised in urine supernatants from infected children compared to controls, whereas high amounts of EPX were found in urine supernatants from infected children as well as from controls. However, the amounts of cell bound ECP and EPX were significantly raised in infected children. In pre-treatment observations significant correlations were demonstrated between egg counts, albuminuria and eosinophiluria as measured by the amount of cell bound ECP and EPX, or ECP in urine supernatants. No such correlations were demonstrated with the amount of EPX in the urine supernatants. Comparable amounts of ECP and EPX could be extracted from the urine deposits from infected children, but due to the high amounts of EPX in urine deposit extracts from controls, extracted ECP gave the best discrimination between infected and non-infected children. While albuminuria disappeared in most children at the 6 week post-treatment follow-up, eosinophiluria persisted in a significant proportion of the treated children indicating continued eosinophil activity in the bladder wall. Detection and quantification of early acute inflammatory reactions using ECP/eosinophils in combination with detection of later stages of bladder pathology using ultrasound may allow for a dynamic evaluation of the pathological process, the morbidity development and post treatment pathological changes in S. haematobium infections.

Diagnosis of female genital schistosomiasis by indirect disease markers: determination of eosinophil cationic protein, neopterin and IgA in vaginal fluid and swab eluates.

Based on assumptions about the pathophysiology of egg-related lesions in the lower reproductive tract, putative indirect disease markers were investigated in vaginal fluids from 54 Malawi adolescent girls and women infected with S. haematobium. These women received a careful gynecological examination during which biopsies were taken from the cervix, and, if present, also from suspicious lesions in the vagina and the vulva. If the biopsies, either in wet crushed preparations or in histological sections, contained eggs the patients were considered to have female genital schistosomiasis (FGS; n = 33). The remainder (n = 21) were classified as having urinary schistosomiasis only. Eosinophil cationic protein (ECP), a cytotoxic granule protein of eosinophils, neopterin, a second messenger molecule generated during the activation of macrophages, and IgA as an indicator of local B-cell activation were quantitatively determined in vaginal fluid. To clarify the origin of ECP, this protein was also looked for in histological sections by an immunohistochemical method. In order to explore whether such disease markers can be detected after absorption to a tampon-like material, ECP and IgA were also assessed after elution from a non-porous, polypropylene fibre web impregnated with vaginal fluid. The concentration of ECP in vaginal fluid and the degree of immunohistochemical staining in histological sections were significantly higher in patients with FGS than in women with urinary schistosomiasis only. The amount of ECP detected in histological sections correlated to the number of eggs/mm2 of compressed genital tissue (rho = 0.36, P = 0.02), and the concentration of ECP in vaginal fluid correlated to the concentration of neopterin as well as to that of IgA (rho = 0.52, P = 0.004 and rho = 0.37, P = 0.02, respectively). Median neopterin concentration in vaginal fluid was also higher in the FGS group, but the difference was not statistically significant. ECP could also be detected in eluates from impregnated fibre webs, but the concentration was approximately one power of 10 less than in the original vaginal fluid. These results demonstrate that indicators of immunological mechanisms related to the egg-granuloma might be useful as indirect disease markers for women with FGS if assessed in vaginal washings or swab eluates.

Reversibility of lower reproductive tract abnormalities in women with Schistosoma haematobium infection after treatment with praziquantel--an interim report.

Little is known whether and to what extent antiparasitic treatment cures female genital schistosomiasis (FGS). Using a standard protocol, of twenty-one women with FGS nine were re-examined at two to nine weeks after they had been treated with praziquantel at a single dose of 40 mg/kg. Symptoms related to pathology of the urinary tract and to a lesser extent of genital pathology subsided in most patients. Schistosoma haematobium ova were no longer detectable in urine of any of the patients post-treatment. Efficiency of chemotherapy against adult worms was confirmed by the disappearance of circulating anodic antigen (CAA) in serum. Sandy patches showed resolution in two of four cases after chemotherapy. Papillomata due to schistosomiasis alone improved, but persisted in mixed infection with human papilloma virus (HPV) or when HPV was the only underlying cause. In one patient ulcera could not be related with certainty to schistosomiasis at admission, but resolved after treatment with parziquantel. Leukoplakia (two cases) was not influenced by chemotherapy, or even increased during follow-up, regardless of whether ova had been detected or not. Although the follow-up period was rather short, time intervals were not standardized, and a relatively small number of patients was investigated, it could be shown that genital pathology due to sequestered S. haematobium ova is, at least partially, reversible already two to nine weeks after killing the adult worms by praziquantel. This is paralleled by a normalization of inflammatory immune responses detectable in histological sections and vaginal lavage.

Human blood eosinophils produce and secrete interleukin 4.

Interleukin 4 (Il-4) is an immunoregulatory cytokine which induces T-cell proliferation and differentiation into a Th2 phenotype, and is of particular importance for the induction of IgE synthesis. In the present study, the capability of human peripheral blood eosinophils from allergic and non-allergic donors to produce Il-4 was examined. Using reverse transcribed polymerase chain reaction (RT-PCR), it was shown that highly purified eosinophils from allergic patients express mRNA for Il-4. Resting eosinophils also gave specific immunoreactivity with anti-Il-4 antibodies, consistent with translation of Il-4 mRNA. Light and electron microscopic immunocytochemistry revealed that Il-4 was prestored in the eosinophilic granules. These results were confirmed by Il-4 specific ELISA which showed that Il-4 production could be upregulated in the eosinophils and released from the eosinophils following stimulation with the calcium ionophore A23187. These data indicate that eosinophils may be an important source of Il-4 at sites of allergic inflammation. Thus, eosinophils may act as immunomodulatory cells enhancing the allergic response through formation of Th2-cells and inducing the isotype switching to IgE in human B-cells.

Eosinophil cationic protein- and eosinophil-derived neurotoxin/eosinophil protein X-immunoreactive eosinophils in prurigo nodularis.

It is known that eosinophils are actively involved in allergy and inflammation. The granular components of eosinophils, eosinophil cationic protein (ECP) and eosinophil-derived neurotoxin/eosinophil protein X (EDN/EPX), play an important role in such allergic and inflammatory processes. Prurigo nodularis is a chronic inflammatory skin disease with obvious cutaneous nervous involvement. To detect ECP and EDN/ EPX expression in the eosinophils and their relation to nerve fibres in prurigo nodularis, ECP and EDN/EPX single-labelling immunofluorescence, and ECP and PGP 9.5 double-labelling immunofluorescence, were performed. In prurigo nodularis lesional skin, the ECP- and EDN/EPX-containing cells, which were mainly distributed in the upper dermis, were significantly increased in number compared to their numbers in uninvolved and normal skin. The immunoreactivity of ECP and EDN/EPX in prurigo lesional skin was stronger than in uninvolved skin or control skin. The PGP 9.5-immunoreactive nerves were also increased in number in the areas where there were increased eosinophils. The nerves were in close proximity to eosinophils, and occasionally even seemed to be in contact. The present results indicate that the cutaneous nerves and the ECP- and EDN/EPX-containing eosinophils are possibly involved in the pathogenesis of the disease. The close relationship of nerves and eosinophils indicates that the cutaneous nerves may influence eosinophil function in the chronic inflammatory states of prurigo nodularis. ECP and EDN/EPX could thus be released to the local tissue and modulate the inflammation of the prurigo nodularis lesion.

Bioactive substance accumulation and septic complications in a burn trauma patient: effect of perioperative blood transfusion?

Evidence has emerged that suggests adverse effects to perioperative homologous blood transfusion are related to the age of the blood products. Recently, time-dependent accumulation of bioactive substances in red cell suspensions, standard platelet concentrates and fresh frozen plasma during storage have been shown. The potential adverse effects of these bioactive substances were analysed in a burn trauma patient. A patient with 40 per cent second and third degree burn trauma without other injuries underwent a two-step transplantation operation. Samples for analyses of histamine, eosinophil cationic protein (ECP), eosinophil protein X (EPX), neutrophil myeloperoxidase (MPO) and interleukin 6 (IL-6) were drawn frequently from the patient before, during and after the operations, and from all transfused red cell, platelet and fresh frozen plasma units. Urine was sampled every hour during the first operation for analyses of ECP and EPX excretion. All analyses were performed by ELISA and RIA methods, and results compared to patient outcome. The patient received a total of 48 and 8 SAGM blood, 6 and 0 platelet and 12 and 4 fresh frozen plasma units at the two operations, respectively. Transfused products contained a total of 64.54 nmol and 17.50 nmol histamine, 115518 ng and 25764 ng ECP, 174457 ng and 38770 ng EPX, 6950915 ng and 1505125 ng MPO, and 14740 pg and 5600 pg IL-6 at the two operations, respectively. The accumulation of the substances in patient plasma correlated to postoperative septic reactions, without any disclosure of bacteraemia after the first operation, while the accumulation at the second operation correlated to the septic reaction and Pseudomonas aeruginosa infection. Time-dependent accumulation of bioactive substances in blood products during storage may be related to the development of post-transfusion adverse effects.

Prestorage leukocyte filtration may reduce leukocyte-derived bioactive substance accumulation in patients operated for burn trauma.

Adverse effects of perioperative blood transfusion appear to be storage-time-dependent and may be related to extracellular accumulation of bioactive substances in blood products. In this study the clinical effects of leukofiltered and non-filtered blood products in patients undergoing surgery for burn trauma are investigated. 24 consecutive patients were randomly selected to receive transfusion with non-filtered blood components (group A, n = 12) or similar products, which were prestorage leukofiltered (group B, n = 12). The burn injury was scored using the Bull and Fischer index of age and burn surface area. Histamine, interleukin-6 (IL-6), plasminogen activator inhibitor-1 (PAI-1), eosinophil cationic protein (ECP) and myeloperoxidase (MPO) were analysed in plasma or serum collected from all patients 30 min before skin incision, at skin incision and 5, 10 and 30 min and thereafter every 30 min after skin incision until the grafts were secured by wrapping. Samples were also taken 8 h after skin incision and in the morning of postoperative days 1-5. The amount of blood products transfused from admission until day 5 postoperatively was recorded. All patients were followed until discharge or death. The Bull and Fischer index was comparable in the two groups. Prestorage leukofiltration reduced the amount of blood products required for transfusion significantly (p < 0.05) compared with non-filtered products. The levels of the various bioactive substances changed during and after the operation. In particular, ECP and MPO levels increased significantly (p < 0.05) in group A patients compared with unchanged (ECP) or decreased (MPO) levels in group B patients. IL-6 analyses showed, that the trauma had more severe impact on group B patients than on group A patients. Nevertheless, 4 patients died in group A and 2 in group B; all with a Bull and Fischer index between 1.0 and 2.0. Prestorage leukocyte filtration may reduce transfusion related accumulation of various bioactive substances and the requirement for blood in burn trauma patients.

In vitro Release of Eosinophil Proteins in Allergic and Atopic Dermatitis Patients.

To investigate whether eosinophils are stimulated in vivo or have acquired an increased susceptibility to stimuli from the coagulation cascade, the release of eosinophil proteins was compared for three groups of donors with different levels of serum IgE. (1) with atopic dermatitis (s-IgE > 5000 IU/ml, n = 11); (2) with inhalant allergy (200 < s-IgE < 2 000 IU/ml, n = 10); and (3) non-allergic (s- IgE < 100 IU/ml, n = 10). The levels of eosinophil cationic protein and eosinophil protein X (ECP, EPX) were determined in serum (clotting time = 2.0 h) and plasma. Serum and plasma ECP in normal donors demonstrated large intra-personal variations (C.V. 50-80%), but serum-ECP (mean 8.1 ng/ml) was clearly distinguishable from plasma ECP (mean 1.0 ng/ml) by a factor of 8 (range: 5.6-11.6). The ECP released during clotting was markedly increased in the atopic dermatitis group (serum:plasma ratio 13.5, p < 0.003) compared with the other groups (6.7 and 5.6). EPX, having a higher plasma level, demonstrated a less pronounced release (serum: plasma ratios 2.0, 1.7 and 1.4), with no statistical difference between donor groups. Considering all donors together the levels of ECP and EPX in plasma and in serum were correlated to the number of eosinophils (coefficients of correlation 0.54-0.58, p < 0.002).