The apicomplexan parasite Cryptosporidium causes diarrheal disease worldwide. Proteolytic processing of proteins plays a significant role in host cell invasion by apicomplexan parasites. In previous studies, we described gp40/15, a Cryptosporidium sp. glycoprotein that is proteolytically cleaved to yield two surface glycopeptides (gp40 and gp15), which are implicated in mediating infection of h...

The effect of Corynebacterium parvum on the immune response of C57BL/6 mice (H-2b) to the allogeneic leukemia L1210 (H-2d) was investigated. Mice were either left untreated or given C. parvum i.v. or i.p. in various dosages. Seven days later they were challenged with 2.5 to 10 X 10(6) live L1210 cells i.p. Control animals almost always rejected the challenge. In contrast, most mice pretreated w...

Mycoplasma parvum [Eperythrozoon parvum] is the second hemotrophic mycoplasma (hemoplasma) described in pigs. Unlike M. suis, its closest phylogenetic relative, M. parvum, is considered a non-pathogenic bacterium in this host species. Natural infection of a domestic, 6-month-old splenectomized pig with M. parvum strain Indiana is described herein. Light and scanning electron microscopy of the b...

Elevated levels of nitric oxide (NO2-/NO3-) were detected in the serum of mice 3-7 days after priming with Corynebacterium parvum (Propionibacterium acnes). The serum NO2-/NO3- response was completely inhibited when C. parvum-primed (C. parrum) mice were treated with N(G)-monomethyl-L-arginine (L-NMMA) or aminoguanidine (AG) on days 6 and 7 post priming. The response was also inhibited when the...

Corynebacterium parvum administered in mice prior to herpes simplex virus (HSV) infection significantly protected them against lethal encephalitis. This was seen both with a mouse strain highly susceptible to HSV and with one relatively resistant to HSV. Mice immunosuppressed by cyclophosphamide and showing an increased mortality after HSV infection were also protected by C. parvum pretreatment...

Fecal droppings of migratory Canada geese, Branta canadensis, collected from nine sites near the Chesapeake Bay (Maryland), were examined for the presence of Cryptosporidium parvum and Giardia spp. Cryptosporidium sp. oocysts were found in feces at seven of nine sites, and Giardia cysts were found at all nine sites. The oocysts from three sites were infectious for mice and molecularly identifie...

cryptosporidiosis is a gastroenteric disease caused by the protozoan parasite cryptosporidium parvum. water–borne transmission of this organism has become more prevalent in recent years. current method for detection of c. parvum oocysts in water is immunofluoresence assay (ifa). the method is time consuming, laborious and particularly not–specific. it cannot determine the infectivity of detecte...

Toxin production is widespread among aquatic microalgae, suggesting a functional advantage for organisms producing toxic compounds. However, the biological role of algal toxin production is only vaguely understood. Here, we show that excretion of a toxic substance in the phagotrophic phytoflagellate Prymnesium parvum (Prymnesiophyceae) constitutes a mechanism to immobilize and seize motile prey...

Corynebacterium parvum induces rapid proliferation of spleen cells with concomitant rapid increases in DNA synthesis as measured by [3H]thymidine uptake and increase in DNA polymerase activity. Cell number increased exponentially over 10 days. DNA polymerase activity increased 8-fold after C. parvum stimulation. The rapidity of response indicated a population response to the stimulus, and the d...

background: cryptosporidium parvum causes severe gastroenteritis in immunocompromised human and new borne animals. the organism can be transmitted through water. since small number of c. parvum is infectious, the aim of the present study was to develop a chromatography method for the isolation of c. parvum oocyst in samples with limited number of oocysts. methods: antibody was prepared against ...