Effect of chronic alcohol intake on hepatic fibrosis and granulomas in murine schistosomiasis mansoni

In consideration of the vast prevalence of schistosomiasis and heavy alcohol consumption in many parts of the world, the possibility of an interaction between these two conditions inducing liver disease was studied in mice infected with Schistosoma mansoni. Alcohol consumption significantly reduced by 25% the mean granuloma diameter and by about 60% the extent of fibrous tissue deposition determined chemically as hydroxyproline. DNA, as an expression of the inflammatory and cellular components of the granulomatous reaction in the infected animals, was also significantly reduced by alcohol consumption. These results indicate the need for epidemiological studies in the clinical manifestations and course of schistosomiasis in human alcoholics.

Quantification, dynamics, and mechanisms of pulmonary inflammatory response around schistosomula of Schistosoma mansoni

The inflammatory response around schistosomula injected into the lungs of uninfected mice and mice infected with Schistosoma mansoni was quantified. In uninfected mice, the inflammatory response started at 1 hour and peaked at 6 days, whereas in the infected mice, the inflammatory response was accelerated and peaked at 24 hours. This latter inflammatory reaction was 1.5 times greater than the 6-day reaction found in uninfected controls. Neutrophils and mononuclear cells were seen around schistosomula impacted into the pulmonary microvasculature by 1 hour; later, however, eosinophils constituted the predominant cell. This augmented inflammatory response was detected in mice infected with S mansoni first at 4 weeks after injection and peaked at 12 weeks. The augmented response correlated with acquired resistance as assayed by the recovery of the organisms from the lungs 4 days after challenge. Augmented inflammatory reaction and increased protection was induced by subcutaneous sensitization with dead schistosomula or eggs but not by cercariae or adult worms. Adoptive transfer of serum but not lymphoid cells from 12-15 week-infected mice resulted in augmented inflammation and enhanced resistance in recipient normal animals. The serum activity was absorbed by both schistosomula and eggs and was shown to reside in the fraction containing IgG1.

Immunopathology of murine infection with Schistosoma mansoni: relationship of genetic background to hepatosplenic disease and modulation

The influence of genetic factors on the manifestations of disease associated with infection with Schistosoma mansoni (portal hypertension, liver granulomas, hepatosplenomegaly) and their modulation were studied in inbred strains of mice. Three groups were identified according to the degree of portal hypertension: high (portal venous pressure, 19.1 cm H2O: DBA/1J), intermediate (8.9-13.4 cm H2O; BALB/cJ, DBA/2J, CBA/CaJ, C3H/HeJ, and BUB/BnJ), and low responders (6.1 cm H2O; C57BL/6J). Granuloma size, organomegaly, and portal venous pressure were strain dependent and not H-2 dependent and were determined by more than one gene. Studies of schistosomiasis in the F1 generation of high and low responders indicated that more than one gene is involved. Modulation of portal venous pressure between eight and 20 weeks of infection occurred in C57BL/6J but not in BALB/cJ mice and was transferable with immune lymphoid cells. These data indicate that disease associated with infection with S. mansoni and its modulation in mice are influenced by the genetic (non-H-2) background of the host and dependent in part on cell-mediated immunity.

Antigranulocyte antibodies and deranged immune function associated with phenytoin-induced serum sickness

A phenytoin-associated serum-sickness-like syndrome was followed by severe pancytopenia in a 17-year-old female. Serum obtained during the acute phase of her illness contained antibodies against homologous eosinophils and neutrophils, antibodies against autologous neutrophils, and antibodies to phenytoin. The serum also inhibited bone marrow granulocyte colon formation in vitro. Lymphocyte transformation by pokeweed mitogen was impaired and, after recovery, the patient's lymphocytes were transformed in vitro by the addition of phenytoin. These data demonstrate that profound derangements of immunity can be associated with a phenytoin-induced serum-sickness-like illness.

Peroxidase-mediated toxicity to schistosomula of Schistosoma mansoni

Guinea pig eosinophil peroxidase (EPO) was capable of killing schistosomula of Schistosoma mansoni in vitro when combined with hydrogen peroxide and a halide. Killing was measured by 51Cr release, by microscopic evaluation of viability, and by reinfection experiments in mice. Parasite killing was dependent on each component of the EPO-H2O2-halide system, was completely inhibited by catalase and azide, and was partially inhibited by cyanide. The EPO-mediated system required 10(-4) M H2O2 and 10(-4) M iodide at pH 7.0, and the schistosomula were killed with exposure to this system of less than 30 min at 37 degrees C. At pH 6.0, the EPO-mediated system showed significant cidal activity with 10(-6) M iodide. Canine neutrophil peroxidase (myeloperoxidase [MPO]) was also able to kill schistosomula in vitro in the presence of 10(-4) M H2O2 and 10(-4) iodide at pH 7.0 and pH 6.0. Physiologic concentrations of chloride (0.1 M) could substitute for iodide at pH 7.0 and pH 6.0 as the halide cofactor; however, at pH 7.0, a higher concentration of enzyme was required. These findings with isolated enzyme systems are compatible with a role for peroxidase in the host defense against schistosomula.

Peroxidase-mediated toxicity to schistosomula of Schistosoma mansoni

Guinea pig eosinophil peroxidase (EPO) was capable of killing schistosomula of Schistosoma mansoni in vitro when combined with hydrogen peroxide and a halide. Killing was measured by 51Cr release, by microscopic evaluation of viability, and by reinfection experiments in mice. Parasite killing was dependent on each component of the EPO-H2O2-halide system, was completely inhibited by catalase and azide, and was partially inhibited by cyanide. The EPO-mediated system required 10(-4) M H2O2 and 10(-4) M iodide at pH 7.0, and the schistosomula were killed with exposure to this system of less than 30 min at 37 degrees C. At pH 6.0, the EPO-mediated system showed significant cidal activity with 10(-6) M iodide. Canine neutrophil peroxidase (myeloperoxidase [MPO]) was also able to kill schistosomula in vitro in the presence of 10(-4) M H2O2 and 10(-4) iodide at pH 7.0 and pH 6.0. Physiologic concentrations of chloride (0.1 M) could substitute for iodide at pH 7.0 and pH 6.0 as the halide cofactor; however, at pH 7.0, a higher concentration of enzyme was required. These findings with isolated enzyme systems are compatible with a role for peroxidase in the host defense against schistosomula.

Dichotomies in the reactivity to worm antigen in human schistosomiasis mansoni

3H-thymidine incorporation was studied using peripheral blood mononuclear cells (PBMC) from 41 Egyptians with Schistosoma mansoni infection. The individuals were preselected to fall into 3 age-matched categories: asymptomatic with light and heavy infections and those with schistosomal hepatosplenomegaly. Seven uninfected individuals served as controls. PBMC from all groups were comparable in their responsiveness to phytohemagglutinin (PHA), streptokinase-streptodornase (SKSD), and the schistosome soluble egg antigen (SEA). However, DNA synthesis induced by soluble worm antigenic preparation (SWAP) differed significantly among these groups. The mean response to SWAP (delta cpm = experimental cpm minus control cpm +/- standard error) was markedly decreased in individuals with heavy infections (1,963 +/- 509) compared with those with light to moderate egg excretion (4,646 +/- 790; p less than 0.01). Moreover, 2 subgroups were discernible among patients with hepatosplenomegaly. Seven were unresponsive to SWAP (7659 +/- 231), whereas 13 had vigorous responses (14, 617 +/- 2263; p < 0.01). This is the first demonstration of an inverse relationship between specific immune responsiveness to adult worm antigens and intensity of infection in humans with schistosomiasis mansoni. The depressed lymphocyte reactivity in patients with heavy infection, whether cause or consequence of the parasite load, may perpetuate large worm burdens. Furthermore, the observations on patients with hepatosplenomegaly may reflect differing pathogenetic mechanisms.

Dichotomies in the reactivity to worm antigen in human schistosomiasis mansoni

3H-thymidine incorporation was studied using peripheral blood mononuclear cells (PBMC) from 41 Egyptians with Schistosoma mansoni infection. The individuals were preselected to fall into 3 age-matched categories: asymptomatic with light and heavy infections and those with schistosomal hepatosplenomegaly. Seven uninfected individuals served as controls. PBMC from all groups were comparable in their responsiveness to phytohemagglutinin (PHA), streptokinase-streptodornase (SKSD), and the schistosome soluble egg antigen (SEA). However, DNA synthesis induced by soluble worm antigenic preparation (SWAP) differed significantly among these groups. The mean response to SWAP (delta cpm = experimental cpm minus control cpm +/- standard error) was markedly decreased in individuals with heavy infections (1,963 +/- 509) compared with those with light to moderate egg excretion (4,646 +/- 790; p less than 0.01). Moreover, 2 subgroups were discernible among patients with hepatosplenomegaly. Seven were unresponsive to SWAP (7659 +/- 231), whereas 13 had vigorous responses (14, 617 +/- 2263; p &lt; 0.01). This is the first demonstration of an inverse relationship between specific immune responsiveness to adult worm antigens and intensity of infection in humans with schistosomiasis mansoni. The depressed lymphocyte reactivity in patients with heavy infection, whether cause or consequence of the parasite load, may perpetuate large worm burdens. Furthermore, the observations on patients with hepatosplenomegaly may reflect differing pathogenetic mechanisms.

Role of cell-generated hydrogen peroxide in granulocyte-mediated killing of schistosomula of Schistosoma mansoni in vitro

Human as well as murine granulocytes have been shown to kill the larval stages of helminth parasites; the mechanism of this cell-mediated cytotoxicity is, however, poorly understood. The present study was designed to assess the role of peroxidative processes in killing of schistosomula of Schistosoma mansoni by human granulocytes in vitro. The rate of H(2)O(2) production by human neutrophils, eosinophils, and basophils was measured upon incubation with schistosomula alone or in the presence of specific antibody or complement. Opsonized parasites (antibody and/or complement) increased the rate of H(2)O(2) production by neutrophils, eosinophils, and basophils by respective percentages of 500, 500, and 371. The rate of H(2)O(2) release was directly related to the number of granulocytes and to the proportion of cells attached to the surface of the schistosomula. Increased hydrogen peroxide release occurred by 10 min of incubation and was demonstrable up to 16 h after addition of leukocytes to schistosomula. The primary source of this oxygen product was found to be the granulocytes adherent to the schistosomula and not those that remained unattached. Hydrogen peroxide production by neutrophils and eosinophils was quantitatively similar (schistosomula coated with antibody plus complement stimulated 5 x 10(6) neutrophils and eosinophils to release H(2)O(2) at respective rates of 0.35 and 0.40 nmol/min). Granulocyte-mediated parasite killing correlated with rate of H(2)O(2) generation; both processes were inhibited by catalase. To define further the role of oxidative metabolites, neutrophils and eosinophils of two subjects with chronic granulomatous disease were used; marked reduction of granulocyte-mediated parasite mortality was observed. Peroxidase was required for H(2)O(2)-mediated killing. Addition of the peroxidase inhibitors azide (1 mM), cyanide (1 mM), or aminotriazole (1 cM) to neutrophilschistosomula mixtures significantly reduced parasite cytotoxicity (P < 0.01); similar reduction was observed when eosinophils were used (P < 0.01). Fixation of halide (iodide) to trichloroacetic acid-precipitable protein (2.4-6.0 nmol/h per 10(7) neutrophils) was demonstrated in the presence of granulocytes, opsonins, and parasites; this process was completely inhibited by 1 mM azide. These data indicate that contact between the surfaces of human granulocytes and schistosomula results in release of cellular hydrogen peroxide and iodination. The generation of H(2)O(2) and its interaction with peroxidase appear to be crucial in effecting in vitro granulocyte-mediated parasite cytotoxicity.

Role of host granulomatous response in murine schistosomiasis mansoni. eosinophil-mediated destruction of eggs

Eosinophils form 50% of cells in the host granulomatous response to Schistosoma mansoni eggs, but their functional role in these granulomas and their relation to egg destruction is unknown. We have studied the course of S. mansoni infection in mice treated with normal rabbit serum (NRS) or depleted of their eosinophils by monospecific anti-eosinophil serum (AES). At 6-wk of infection (after 2 wk of egg deposition) the AES-treated animals were similar to NRS-treated controls with the exception that hepatic granulomas in the AES-treated animals were 50% smaller and devoid of eosinophils. At 8 wk of infection, AES-treated mice had significantly higher mortality, spleen weight, portal pressure, and 80% more eggs retained in their livers. These data suggest that eosinophil depletion delayed egg destruction. We subsequently studied destruction of eggs injected into the pulmonary microvasculature of sensitized mice. 2,000 S. mansoni eggs were intravenously injected into the tail veins of mice treated with NRS, anti-neutrophil serum, AES or ATG (anti-thymocyte globulin); at time intervals the remaining eggs were recovered from the lungs by tissue digestion. Egg recovery from NRS- or anti-neutrophil serum-treated mice began to decrease by day 16 and the percent recovery of eggs at day 24 was 55 and 52%, respectively. In contrast, animals treated with AES had smaller lung granulomas that were devoid of eosinophils and a marked delay of egg destruction was seen. It took until day 44 for 50% of the eggs to be destroyed. In ATG-treated animals smaller granulomas were seen that had diminished lymphocytes and also 75% less eosinophils. ATG treatment apparently slowed egg destruction but was not statistically significant. Our data define the role of the eosinophils in destruction of schistosome eggs in vivo and delineates the protective function of these cells within the host granulomatous response.

Stimulation of eosinophil production in vitro by eosinophilopoietin and spleen-cell-derived eosinophil growth-stimulating factor

Eosinophilopoietin (EPP) was previously characterized by the ability to stimulate eosinophil production in vivo, but these studies could not ascertain whether EPP had a direct effect on the bone marrow or acted indirectly by causing release of eosinophilopoietic activity by other tissues. The present studies demonstrate that EPP stimulates eosinophil growth in liquid culture of mouse bone marrow in vitro. The timing of stimulation by EPP in vivo and in vitro were parallel, with maximal eosinophil growth after 48 hr. Moreover, EPP appears similar to, and possible identical with, the eosinophil growth-stimulating substance (EO-GSF) released by antigenic stimulation of immune nonadherent spleen cells. Both EPP and EO-GSF are of low molecular weight, both produce stimulation of eosinophil growth with identical kinetics, and both produced similar dose-response curves in the liquid culture system.

Suppression splenic T lymphocytes in human hepatosplenic Schistosomiasis mansoni

Splenic suppressor cell activity was evaluated in 10 patients with advanced hepatosplenic Schistosomiasis mansoni undergoing elective splenectomy. We used cell mixing experiments to assess the effect of mitomycin-C-treated spleen cells on antigen and mitogen-induced 3H-thymidine incorporation of responder cells. The suppressor to responder ratio was 1.0. Spleen cells from 7 of 10 patients caused at least 20% suppression of phytohemagglutinin-induced 3H-thymidine incorporation of one or more populations of responder cells (spleen cells, autologous and allogeneic peripheral blood mononuclear cells)Responses of peripheral blood mononuclear cells to streptokinase-streptodornase and schistosome soluble egg and worm antigen preparations also were inhibited by co-cultured spleen cells. An inverse correlation was apparent between the spleen cell response to PHA and the suppressor activity of that spleen cell population (r = -0.74, p less than 0.05). Cell purification procedures showed that the active suppressor splenic cell was non-adherent and rosetted neuraminidase-treated sheep erythrocytes. This splenic suppressor T lymphocyte may modulate splenic and peripheral blood lymphocyte responses in patients with hepatosplenic schistosomiasis.

Suppression splenic T lymphocytes in human hepatosplenic Schistosomiasis mansoni

Splenic suppressor cell activity was evaluated in 10 patients with advanced hepatosplenic Schistosomiasis mansoni undergoing elective splenectomy. We used cell mixing experiments to assess the effect of mitomycin-C-treated spleen cells on antigen and mitogen-induced 3H-thymidine incorporation of responder cells. The suppressor to responder ratio was 1.0. Spleen cells from 7 of 10 patients caused at least 20% suppression of phytohemagglutinin-induced 3H-thymidine incorporation of one or more populations of responder cells (spleen cells, autologous and allogeneic peripheral blood mononuclear cells)Responses of peripheral blood mononuclear cells to streptokinase-streptodornase and schistosome soluble egg and worm antigen preparations also were inhibited by co-cultured spleen cells. An inverse correlation was apparent between the spleen cell response to PHA and the suppressor activity of that spleen cell population (r = -0.74, p less than 0.05). Cell purification procedures showed that the active suppressor splenic cell was non-adherent and rosetted neuraminidase-treated sheep erythrocytes. This splenic suppressor T lymphocyte may modulate splenic and peripheral blood lymphocyte responses in patients with hepatosplenic schistosomiasis.

Role of arginase in killing of schistosomula of Schistosoma mansoni

Nonspecific resistance to the multicellular organism Schistosoma mansoni can be induced in mice by several infectious agents. We utilized the observed genetic restriction of such acquired resistance to study the mediators of killing of the larval stage of S. mansoni in vitro. Adherent peritoneal cell monolayers from Corynebacterium parvum-treated C57BL/6J but not from C. parvum-treated BALB/cJ mice killed an increased proportion of schistosomula in 24 h. Activated macrophages (Mphi) from both strains exhibited enhanced H(2)0(2) production after incubation with the parasites or phorbol myristate acetate. Thus H(2)0(2) production was not associated with schistosomula killing. Moreover, schistosomula killing was unaffected by catalase or superoxide dismutase. In contrast, activated C57BL/6J (but not BALB/cJ) Mphi released fourfold more arginase into supernates than control Mphi. Schistosomula killing by these Mphi correlated with arginase content of the supernates, was exaggerated in arginine-poor medium, and could be blocked by the addition of arginine. Exogenous bovine arginase added to Fischer's medium without macrophages produced comparable parasite mortality. Our data suggest that arginase is a critical mediator of in vitro killing of this multicellular organism by activated macrophages.

Induction of resistance to Schistosoma mansoni by natural cord factor and synthetic lower homologues

Resistance to schistosomiasis in mice can be acquired either specifically, by primary infection with Schistosoma mansoni, or nonspecifically, by treatment with a variety of unrelated agents such as bacille Calmette-Guérin. Several immunoadjuvants related to mycobacteria were examined for their ability to induce resistance to schistosomiasis. Natural cord factor (6,6'-trehalose dimycolate), a 100-carbon synthetic cord factor analogue, and dipalmitate trehalose induced significant protection. Trehalose dibehenate and muramyl dipeptide did not induce consistent protection. Since protection acquired by primary schistosomal infection or by any of these potentiating agents is partial, their possible additive effect was evaluated. The resistance of mice with schistosomiasis that were injected with trehalose dipalmitate and challenged with schistosomal cercariae was increased, as assayed by recovery of schistosomula from the lungs and of adult worms from the portal system. Thus, these synthetic adjuvants not only induce partial protection against schistosomiasis, but also significantly enhance acquired immunity in mice with primary infections.

Quick Kato smear for field quantification of Schistosoma mansoni eggs

The 50-mg Kato thick smear was modified by using stainless steel templates which deliver 20 mg of stools accurately; fecal material can thus be processed in the field and the smears cleared within 15 minutes. The counts obtained from the 20-mg quick Kato were proportional to those obtained by the 50-mg thick smear.

The role of eosinophils in granulopoiesis. I. Eosinophilia in neutropenic patients

The role of eosinophils in granulopoiesis is unclear. In a variety of conditions, the level of eosinophils is inversely related to the level of neutrophils. The present report describes two patients with eosinophilia and neutropenia and examines the in vitro effects of eosinophils on the colony formation of their bone marrow in semisolid culture medium. The addition of autologous eosinophils to bone marrow cultures from these patients resulted in a decrease in the number of colonies; in contrast, antieosinophilic serum increased the number of colony-forming units. Indomethacin, an inhibitor of prostaglandin, was capable of reversing the effects of added eosinophils. The findings suggest that eosinophils have an inhibitory effect on in vitro granulopoiesis. The suppressive effects may be due to the high content of prostaglandin E found in eosinophils. A schematic diagram based on the current knowledge of the mechanism of granulopoiesis is presented.

Deficient production of the lymphokine eosinophil stimulation promoter in chemically induced and mutation diabetes mellitus in mice

The cellular defects possibly responsible for diminished in vivo granuloma formation in diabetic Schistosoma mansoni-infected mice were investigated. Diabetic and control animals develop a similar degree of eosinophilia. Eosinophils obtained from diabetic mice also respond normally to the lymphokine eosinophil stimulation promoter (ESP). Lymphoid cells of chemically induced (streptozotocin) and mutation diabetic (db/db) mice, however, have a decreased capacity to produce/secrete ESP in response to soluble egg antigens of S. mansoni. Administration of insulin to diabetic mice is associated with a partial reversal of the decreased ability of their lymphoid cells to generate ESP. These findings show that defective cellular immunity in diabetic animals may be partially explained by the failure of their lymphocytes to produce the soluble mediators involved in recruitment of target cells.

Histocompatibilty-linked susceptibility for hepatospleenomegaly in human schistosomiasis mansoni

In schistosomiasis mansoni, the pathogenesis of hepatosplenic disease has been shown to be due primarily to immune mechanisms. The present study was designed to examine the relationship between the development of schistosomal hepatosplenomegaly in Egyptian school children and the HLA antigens. Two groups of schistosome-infected children with similar fecal egg counts were examined: one group (23 children) had no clinically demonstrable hepatosplenomegaly whereas all the children (28) in the second group suffered from liver enlargement. Furthermore, 13 of the 28 individuals in the latter group had splenomegaly as well. Our results show that hepatosplenomegaly was related to the presence of two HLA antigens: HLA AI and B5. The average relative risk of developing hepatomegaly is 29 for HLA AI and 18.9 for 55.6. Furthermore, the severity of hepatomegaly was correlated with the presence of these two HLA antigens. These findings represent a step toward elucidating the factors controlling the pathogenic mechanisms in human schistosomiasis mansoni.

Schistosomiasis haematobia in coast province Kenya. Relationship between egg output and morbidity

Several studies of schistosomiasis haematobia in Africa have revealed a correlation between intensity of infection as measured by urine egg counts and severity of disease as determined by intravenous pyelography. The present study consisted of a survey of 390 school children in the coastal area of Kenya involving a single egg count, and intravenous pyelograms in a stratified random sample of 69 children; the results showed a greater prevalence of urinary tract disease in those with higher intensities of infection. This survey was then followed by a more detailed study in which nine consecutive daily egg counts were done on 121 children; 17 of these children, subdivided into three groups with different intensities in infection, were given intravenous pyelograms. The results were similar in the 11 children with minimal and moderate counts (averaging, respectively, less than 1 egg and 167 eggs/10 ml urine daily), with approximately 30% having bladder or renal abnormalities. In comparison, all of the six children with heavy counts (averaging 1,288 eggs/10 ml urine daily) had bladder lesions and five of them had renal lesions.