Publications

the role of the liver in immunity to blood-stage murine malaria.	mice vaccinated with fixed parasitized red blood cells and bordetella pertussis can clear an otherwise lethal plasmodium yoelii infection in 7 days; this protection is abolished by splenectomy before vaccination. most mice splenectomized following vaccination were able to clear their infections, although their recovery was delayed. when labelled parasitized red cells were injected into mice during an infection, splenic uptake fell from day 3 onwards while uptake by the liver increased. lymphocyt ...	1980	7439934
characterization of surface proteins and glycoproteins on red blood cells from mice infected with haemosporidia: plasmodium yoelii infections of balb/c mice.	lactoperoxidase-catalysed radio-iodination was used to compare the surface proteins on red cells from plasmodium yoelii-infected with normal balb/c mice. the profile of radio-iodinated proteins separated by sds-polyacrylamide gel electrophoresis was different for infected blood of similar parasitaemia from mice inoculated with different doses of the parasite. inoculation with different doses of the parasite. inoculation with the lower dose resulted in the appearance of a major radio-iodinated pr ...	1980	7443294
immune phagocytosis of plasmodium yoelii-infected erythrocytes by macrophages and eosinophils.	unstimulated peritoneal cells from c57bl mice were allowed to phagocytose in vitro different mixtures of percoll-separated parasitized and non-parasitized erythrocytes (pe and npe) from the blood of mice infected with plasmodium yoelii in the presence of immune and normal serum. immune serum caused a significant enhancement of phagocytosis, and both the number of pe adhering to and/or ingested by 100 macrophages and the number of the latter cells engaged in phagocytosis was increased. the effect ...	1980	7460387
malaria in asplenic mice: effects of splenectomy, congenital asplenia, and splenic reconstitution on the course of infection.	in investigations on the role of the spleen in host defense against malaria, we studied the course of murine malaria in three groups of mice with altered splenic function: congenitally asplenic mice, adult-splenectomized mice, and adult-splenectomized mice which were reconstituted with spleen-cell suspensions. intact mice infected with either plasmodium yoelii or p. chabaudi adami experienced infections which resolved spontaneously, with low mortality. congenitally asplenic and splenectomized-re ...	1980	7446805
[study of gametocytes from the plasmodium "vivax" group: morphology, development in anopheles and infectivity of plasmodium yoelii microgametocytes].	the study of the gametocytes of plasmodium yoelii enabled the differentiation of 4 morphological types: o, i, ii and iii (in a chronological order) and amongst each of these types the differentiation of healthy and altered gametocytes. these morphological data represent a tool for investigations on the biology of the gametocytes of the "vivax" group. preliminary experiments bring informations on the evolution of gametocytes and the mechanisms of their infectivity. 1--in experimentaly infected wh ...	1979	539716
defective resistance to plasmodium yoelii in cba/n mice.	the role of b lymphocytes in resistance to malaria was studied in defective and normal f1 mice derived from cba/n mice, a strain with an x-linked b cell defect. when infected with normally nonlethal plasmodium yoelii, immune defective f1 male mice had higher parasitemias and more prolonged infections than normal f1 mice, as well as a 50% mortality rate. before infection the plasma levels of igm and igg were lower in defective f1 males than normal f1 mice. the polyclonal igm and igg responses of ...	1979	448143
immunosuppression in murine malaria. iv. the secondary response to bovine serum albumin.	the anamnestic antibody response of cba mice to bovine serum albumin was characterized by a rapid production of high-avidity antibody. after 3 weeks both the total amount of antibody and its avidity declined but still remained above those seen in the primary response for at least 6 weeks. the effects of acute plasmodium berghei and plasmodium yoelii yoelii infections upon the induction and the expression of this anamnestic response were studied. mice infected with these malaria parasites respond ...	1979	399334
experimental malaria in the cba/n mouse.	cba/n mice carry an x-linked, recessive gene, which results in the absence of a b cell subset, and is expressed primarily as an inability to respond to a certain class of thymus-independent antigens. we have examined the responses of these mice to the malaria parasite plasmodium yoelii and found that primary infections induced by this parasite are more severe and last longer in mice with x-linked defect than in normal controls. the decreased resistance of the defective mice is associated with a ...	1979	387872
[malaria plasmodia in the mouse. parasitization of mature and immature erythrocytes by plasmodium berghei, plasmodium yoelii and plasmodium chabaudi (author's transl)].	plasmodium berghei parasites (strain k173) in mice with developing immunity changed to a variant type with increased resistance against antibodies and enhanced invasion of mature erythrocytes; on passages in normal mice this variant type retransformed to the normal type (kretschmar 1964). on detailed study, parasites of the variant type showed a markedly decreased predilection for polychromatophilic erythrocytes, leading to slowed multiplication during prepatency, increased invasion of mature er ...	1979	384629
biochemistry of intraerythrocytic parasites. ii. comparative studies in carbohydrate metabolism.	comparative studies were carried out on the glucose catabolism of mouse erythrocytes infected with plasmodium berghei, plasmodium yoelii, babesia rodhaini, babesia microti and anthemosoma garnhami, as well as on uninfected erythrocytes and reticulocytes. the results showed that there was little qualitative difference between the glucose utilization and lactate production of the parasites although quantitative differences between malaria parasites and piroplasms were observed. the rate of glucose ...	1979	386968
biochemistry of intraerythrocytic parasites. i. identification of enzymes of parasite origin by starch-gel electrophoresis.	enzymes of parasite origin were identified by starch-gel electrophoresis. the species of parasite studied were plasmodium berghei, plasmodium yoelii nigeriensis, babesia rodhaini and anthemosoma garnhami. lactate dehydrogenase, glucose phosphate isomerase and (nadp) glutamate dehydrogenase were detected in all species; phosphogluconate dehydrogenase was detected in both plasmodium species but malate dehydrogenase only in p. y. nigeriensis. glucose-6-phosphate dehydrogenase, alanine aminotransfer ...	1979	386967
host defenses in murine malaria: evaluation of the mechanisms of immunity to plasmodium yoelii infection.	the immune response of random-bred mice to infection with a relatively avirulent strain of plasmodium yoelii was measured in terms of parasitemia, splenomegaly, immediate and delayed hypersensitivity to a p. yoelii antigen preparation, resistance to challenge with a virulent variant of p. yoelii, and nonspecific resistance to l. monocytogenes. avirulent p. yoelii produced a self limiting infection which resolved in 21 days. peak parasitemia and splenomegaly were observed at 14 days, and infected ...	1979	422246
ia antigens in serum during different murine infections.	there exists in the mouse a family of i-region-controlled (ia) antigens which carry carbohydrate-defined determinants. these antigens appear in serum as glycolipids and seem to be actively secreted by antigen-activated t-cells. this paper describes the ability of selected viral, bacterial, and protozoal infections of mice to markedly alter the serum levels of these ia antigens. all the infectious agents examined induced substantial augmentation or suppression of serum ia concentrations or both. ...	1979	94905
[new data on the biology of gametocytes of plasmodium yoelii yoelli gathered from morphological characteristics indicating their age].	a morphological study has been made of the gametocytes of p. yoelii (a parasite of rodents belonging to the "vivax" group). the authors distinguish 4 types chronologically ordered. moreover, morphology enables one to predict their infectivity. the morphological analysis represents a tool leading to new data on the biology of gametocytes: loss of infectivity as soon as the parasitaemia becomes high; infectivity restricted to the young stages; concentration of young stages in the blood ingested by ...	1979	108020
development and suppression of a population of late-adhering macrophages in mouse malaria.	changes in phagocytic and adherent cell numbers were compared during the course of infections of mice with plasmodium yoelii (py) and p. berghei (pb) and in vaccinated mice challenged with homologous parasites. nucleated cells in the spleen increased in number in py-infected mice and were maximal at the time of recovery. the number of phagocytic cells increased in parallel, as did the number of blood leucocytes. rates of increase were accelerated in vaccinated mice. changes in pb-infected mice r ...	1979	233150
t-cell immunity to malaria in the b-cell deficient mouse.	some b-cell deficient mice drug-rescued with clindamycin hcl from otherwise lethal infections with plasmodium yoelii resisted subsequent challenge with the same parasite despite the fact that they lacked detectable antibody to plasmodia. parasitemias remained patent but at low levels (less than or equal to 5%) in these mice for prolonged periods of time, suggesting that some t-cell function independent of antibody formation can in part mediate immunity to malaria.	1979	312025
influence of the sex-linked defect in cba/n mice on autoimmune responses to isologous erythrocytes. ability to overcome the defect with age.	normal mice spontaneously develop plaque-forming cells (pfc) specific for antigens on modified self erythrocytes (bromelain-treated mouse erythrocytes [brmrbc] antigens). our study demonstrates that the sex-linked defect that results in the inability of cba/n mice to respond to several t-independent antigens (ti-2 antigens) also regulates the autoantibody response to brmrbc antigens. thus, in cba/n homozygous mice and male f1 offspring of cba/n-mothered crosses, e.g., (cba/n x nzb)f1 males, such ...	1979	315995
lethal plasmodium yoelii malaria: the role of macrophages in normal and immunized mice.	mice were injected with silica or corynebacterium parvum, which, respectively, inhibit and stimulate macrophages in vivo, in an attempt to study the role of macrophages in lethal plasmodium yoelii infection and in mice protected by immunization. in the normal infection, macrophages were able to control parasitaemia for up to 1 week, whereas in immunized mice they appeared to inhibit the sterilizing immune response. a model is proposed in which this dual role of activated macrophages may account ...	1979	317443
immunity to plasmodium yoelii and babesia microti: modulation by the cba/n x-chromosome.	cba/n mice carry an x-linked recessive defect expressed in cells of the b cell lineage. the major deficiency in these mice is an almost complete inability to respond to certain thymus-independent antigens, such as pneumococcal polysaccharide type iii (s iii). we have examined the responses of mice carrying the cba/n x-chromosome to the malaria parasite plasmodium yoelii and the piroplasm babesia microti. we have found that the duration and severity of these infections is increased in mice carryi ...	1979	317444
chronic malarial infection of mice: a comparison of single and multiple infections with plasmodium berghei following p. yoelii.	chronic malarial infection was induced in two groups of balb/c mice by injection of plasmodium yoelii followed by either one or repeated injections of p. berghei. both groups showed a continuing but fluctuating splenomegaly, and a considerably increased reticulocyte count which also varied regularly, over a period of six months. during this time many mice had a very low grade parasitaemia demonstrable by subinoculation of blood into uninfected recipients. mice infected with p. yoelii alone did n ...	1978	366816
protection of mice against plasmodium and babesia infections: attempts to raise host-protective sera.	in an attempt to generate large numbers of mice resistant to plasmodium berghei and babesia rodhaini to be used as donors of antibody-secreting cells for hybridoma production, various methods of inducing resistance to repeated challenge with infected blood cells have been explored. although results of independent experiments varied markedly, prior injection of cba/m mice with bcg, and prior infection of balb/c mice with plasmodium yoelii, were found to be manipulations capable of inducing resist ...	1978	375903
exacerbation of murine malaria by concurrent infection with lactic dehydrogenase-elevating virus.	the simultaneous infection of mice with lactic dehydrogenase-elevating virus (ldv) and plasmodium yoelii resulted in an exacerbated attack of malaria. peak parasitaemia was higher and the patent infection more prolonged in doubly infected mice. the results indicate that contamination with ldv must be considered when a change in parasite virulence is observed, particularly when the parasite is maintained by blood passage in mice.	1978	719954
splenomegaly, enhanced phagocytosis, and anemia are thymus-dependent responses to malaria.	immunologically competent mice and mice with defined immunological deficiencies were infected with plasmodium yoelii. splenomegaly, enhanced phagocytosis, and anemia were most marked in infected mice having intact thymic tissue. whereas the spleens of infected nude mice increased minimally in size, the relative blood hemoglobin levels and the rates of carbon clearance in these mice were similar to those of noninfected, immunologically intact mice. thymus-reconstituted nude mice and b-cell-defici ...	1978	669820
immunosuppression in murine malaria. ii. the primary response to bovine serum albumin.	the primary antibody response to alumadsorbed bovine serum albumin was depressed in cba mice infected with plasmodium yoelii yoelii. responses initiated within approximately 3 weeks of this malaria infection were reduced in quantity, but not in avidity. responses initated later were normal. a depressed primary response was also seen in infected compared to control splenectomized mice; this was accompanied by impaired priming for a secondary response.	1977	608688
cytofluorograf detection of plasmodium yoelii, trypanosoma gambiense, and trypanosoma equiperdum by laser excited fluorescence of stained rodent blood.	samples of rat blood infected with plasmodium yoelii (3% parasitized erythrocytes), trypanosoma gambiense, or trypanosoma equiperdum (greater than 50 trypanosomes per microscope field at 400 x) were fixed with 0.5% glutaraldehyde in phosphate buffered saline, then stained with acridine orange (ao) at 10(-4), 10(-5), or 10(-6) m for 0 to 15 min at 5 c or 25 c and/or ethidium bromide (eb) at 0.05 mg/ml for 20 min at 25 c. stained cells were analyzed with a laser cytofluorograf (bio/physics systems ...	1977	886402
plasmodium yoelii: an inbred model for protective immunization against malaria in balb/c mice.		1977	849768
antibody response in vitro of spleen cells from plasmodium yoelii-infected mice.	the primary antibody response to sheep erythrocytes and dinitrophenylated ficoll of spleen cells from mice infected with plasmodium yoelii was studied in vitro. the response to sheep erythrocytes was enhanced between 2 and 4 days after infection and depressed at later intervals. cell fractionation experiments carried out at the time of immunosuppression indicated a defect of macrophage function. at the same time the response to dinitrophenylated ficoll was normal.	1977	324908
plasmodium yoelii and plasmodium vinckei: the effects of nonspecific immunostimulation on murine malaria.		1977	330190
immunosuppression in murine malaria. i. response to type iii pneumococcal polysaccharide.	acute plasmodium yoelii yoelii and chronic plasmodium berghei malaria infections of cba mice were accompanied by a reduced capacity to give an antibody response to type iii pneumococcal polysaccharide (siii). the depression of response initiated by acute malaria persisted for several weeks after recovery from clinical infection. during chronic infection, and at the peak of acute parasitaemia, virtually no response to siii was detected. a substance which crossreacted serologically with siii was f ...	1977	67996
inhibition of the immune response to whooping cough and tetanus vaccines by malaria infection, and the effect of pertussis adjuvant.	plasmodium yoelii infection of mice depressed their capacity to build up humoral immune response to diphteria vaccine and protective immunity against tetanus toxin. this immunodepression was overcome by freund's complete adjuvant or killed pertussis bacilli (whooping cough vaccine). these results suggest that vaccines should be given in association in malaria endemic area.	1977	869103
the action of metabolic inhibitors on microgametogenesis in plasmodium yoelii nigeriensis.	mature gametocytes of plasmodium yoelii nigeriensis were incubated in vitro with a variety of antibiotics whose activities were directed against dna, rna, protein and microtubule assembly. following incubation for periods between 5 and 90 min, exflagellation was induced and the degree of inhibition produced by each drug was assayed microscopically. the results obtained show that de novo synthesis of axonemes and proteins is essential to the events of microgametogenesis. the inhibitory effect of ...	1977	919692
gametogenesis and fertilization in plasmodium yoelii nigeriensis: a transmission electron microscope study.		1976	4810
schizont-infected cell enrichment in rodent malaria.	mouse erythrocytes parasitized with plasmodium berghei or plasmodium yoelii were separated by ultracentrifugation using preformed isodensity gradients of the discontinuous type. three fractions were obtained following centrifugation, the upper of which contained greater than 90% of all schizont-infected cells added to the gradient. the gradient material, stractan ii, is an arabinogalactan polysaccharide and appears to yield results similar to those available using gradients of bovine serum album ...	1976	789847
influence of rodent malaria on the course of leishmania enriettii infection of hamsters.	plasmodium yoelii infection was established in hamsters, and the effect of this type of malaria on concurrent leishmania enriettii infection was examined. it was found that the course of the l. enriettii infection was affected by p. yoelii and that this effect depended on the relative timing of the two infections. a chronic malarial infection with plasmodium berghei was also established in hamsters, and this was found to affect the course of a concurrent l. enriettii infection in a similar manne ...	1976	786886
a genetic investigation of virulence in a rodent malaria parasite.	the genetic basis of virulence in a line (ym) of plasmodium yoelii yoelii was investigated in a cross with a mild line (a/c). the blood forms of the virulent line developed extensively in mature erythrocytes of mice, causing death of the host within 7 days; infections with the mild line were normally restricted to reticulocytes, infected animals recovering after three weeks. lines ym and a/c differed additionally in enzyme and drug-sensitivity markers. studies on infections established from each ...	1976	1264490
cytology and kinetics of microgametogenesis and fertilization in plasmodium yoelii nigeriensis.	the sexual development of the microgametocyte of plasmodium yoelii nigeriensis may be subdivided into microgametogenesis which includes exflagellation, dispersal of the gametes and fertilization. under our experimental conditions microgametogenesis takes about 8-15 min at 20 degrees c, the duration of this period being inversely related to temperature. exflagellation takes less than 1 min, subsequent dispersal of gametes may continue for 40 min. we find that exflagellation is totally inhibited i ...	1975	1118188
the chemotherapy of rodent malaria, xxiii causal prophylaxis, part ii: practical experience with plasmodium yoelii nigeriensis in drug screening.	data are presented on the causal prophylactic action of about 100 compounds of various types against plasmodium yoelii nigeriensis n67 in mice. examples are given to show how action against pre-erythrocytic schizonts may be differentiated from action on emerging erythrocytic stages. in a series of 35 8-aminoquinolines, all but 10 showed definite causal prophylactic activity at tolerated doses. the data permit the compounds to be ranked in order of activity, and many are shown to be more active i ...	1975	1098590
[blood relapses and modifications of the pre-erythrocytic shizonts of plasmodium yoelii using ethionine].	injections of dl-ethionine during the preerythrocytic period of plasmodium yoeli in thammomys were followed by: 1. a delayed prepatent period; 2. a relapsing parasitaemia with alternatively positive and negative blood at subinoculation of clean mice; 3. a peculiar morphology of the exoerythrocytic schizonts which remain small with a scanty cytoplasm and very few large nuclei. although the authors consider the origin of the relapses to be the rupture of delayed hepatic schizonts under the influen ...	1975	807419
new observations on the malaria parasites of rodents of the central african republic - plasmodium vinckei petteri subsp. nov. and plasmodium chabaudi landau, 1965.	the morphology and enzyme forms of malaria parasites isolated from 50 wild caught specimens of thamnomys rutilans from the central african republic have been studied and three distinct species of plasmodium identified. one species has been confirmed as plasmodium yoelii yoelii. morphological features of both the remaining species correspond to those given by landau (1965) in her original description of plasmodium chabaudi. for one of these species the name p. chabaudi has been retained; the othe ...	1975	1155987
quantification of sporozoite invasion, migration, and development by microscopy and flow cytometry.	there is an important role for in vitro assays to better understand the initial steps of malaria infection. in this section, we describe both microscopy-based and flow cytometry-based sporozoite invasion, migration and development assays with the rodent malaria parasites, plasmodium berghei and plasmodium yoelii, and the human malaria parasite, plasmodium falciparum.	0	22990793
the utility of plasmodium berghei as a rodent model for anti-merozoite malaria vaccine assessment.	rodent malaria species plasmodium yoelii and p. chabaudi have been widely used to validate vaccine approaches targeting blood-stage merozoite antigens. however, increasing data suggest the p. berghei rodent malaria may be able to circumvent vaccine-induced anti-merozoite responses. here we confirm a failure to protect against p. berghei, despite successful antibody induction against leading merozoite antigens using protein-in-adjuvant or viral vectored vaccine delivery. no subunit vaccine approa ...	0	23609325
hiv nonnucleoside reverse transcriptase inhibitors and trimethoprim-sulfamethoxazole inhibit plasmodium liver stages.	although nonnucleoside reverse transcriptase inhibitors (nnrtis) are usually part of first-line treatment regimens for human immunodeficiency virus (hiv), their activity on plasmodium liver stages remains unexplored. additionally, trimethoprim-sulfamethoxazole (tmp-smx), used for opportunistic infection prophylaxis in hiv-exposed infants and hiv-infected patients, reduces clinical episodes of malaria; however, tmp-smx effect on plasmodium liver stages requires further study.	0	23125449