• Parasites, Hosts and Diseases
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• 제47권2호
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• pp.171-174
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• 2009

The antigen location of Cryptosporidium parvum, which stimulates antibody formation in humans and animals, was investigated using infected human sera. Immuno-electron microscopy revealed that antigenicity-inducing humoral immunity was located at various developmental stages of parasites, including asexual, sexual stages, and oocysts. The amount of antigen-stimulating IgG antibodies was particularly high on the oocyst wall. The sporozoite surface was shown to give stimulation on IgG and IgM antibody formation. Trophozoites implicated the lowest antigenicity to humoral immunity, both IgG and IgM, by showing the least amount of gold labeling. Immunogold labeling also provided clues that antigens were presented to the host-cell cytoplasm via feeder organelles and host-parasite junctions.

• Journal of Ecology and Environment
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• 제31권2호
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• pp.161-165
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• 2008

This study was performed for the purpose of monitoring monthly levels of two pathogenic microorganisms, Cryptosporidium and Giardia, from November 2005 to August 2007 in Sangsa Lake. Water temperatures, pH and DO fluctuated seasonally at the study site. Annual mean values of BOD, COD and SS were $0.8\;mg\;L^{-1}$, $2.3\;mg\;L^{-1}$ and $1.9\;mg\;L^{-1}$ respectively. Although there was distinct seasonal variation in water chemistry and chlorophyll $\underline{a}$ concentration, the lake generally contains low concentrations of nutrients and chlorophyll $\underline{a}$. The relative abundance of coliform bacteria was always greater than that of fecal coliform. The fecal coliform bacteria comprised $8.5{\sim}22.1%$ of total coliform bacteria. Seasonal analysis of Cryptosporidium and Giardia levels in the study site showed that in winter (November through February), Cryptosporidium oocysts and Giardia cysts were most abundant ($1.1{\sim}1.8\;{\times}\;10\;cells\;L^{-1}$ and $3.8{\sim}5.1\;{\times}\;10\;cells\;L^{-1}$, respectively), while in summer (July through September) the abundance was lowest ($0.0{\sim}0.3\;{\times}\;10\;cells\;L^{-1}$ and $0.9{\sim}2.9\;{\times}\;10\;cells\;L^{-1}$, respectively). Molecular identification revealed two subtypes of Cyrptosporidium parvum in Sangsa Lake.

• Parasites, Hosts and Diseases
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• 제31권3호
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• pp.223-230
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• 1993

Cryptosporidium의 sporozoite에 대한 단클론항체(C6B6 C4Al)와 merozoite에 대한 단클론항체(Cmg-3)를 크립토스포리디움 오오시스트로 감염시킨, 생후 괄일된 생쥐에 4일 혹은 8일간 경구 투여하여 크립토스포리디움 감염에 미치는 효과를 조사하였다. 투여는 Cmg-3만으로, 혹은 C6B6, C4A1, Cmg-3를 함께 섞은 것으로, 그리고 식염수로 실행하였다. p < 0.05 수준에서 항체투여를 받은 것과 받지 않은 그룹 사이에 현격한 차이가 관찰되었다. Crng-3 한개만으로 투여하였을 때는 4일간 투여하였을 때만 효과가 있었던 반면, 3개의 단클론항체를 함께 투여하였을 때는 4일간. 8일간 모두 기생충의 증식을 현격히 감소시켰다. 이것은 경구투여된 항체가 장내에 기생하는 크립토스포리디움의 증식을 억제한 것을 보여주는 것이며 크립토스포리디움증에 대한 치료약이 없는 상황에서 치료법 개발에 새로운 접근 방법을 제시한다고 판단된다.

• Parasites, Hosts and Diseases
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• 제54권5호
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• pp.631-636
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• 2016

This study aimed to develop a multiplex-touchdown PCR method to simultaneously detect 3 species of protozoan parasites, i.e., Cryptosporidium parvum, Giardia lamblia, and Cyclospora cayetanensis, the major causes of traveler's diarrhea and are resistant to standard antimicrobial treatments. The target genes included the Cryptosporidium oocyst wall protein for C. parvum, Glutamate dehydrogenase for G. lamblia, and 18S ribosomal RNA (18S rRNA) for C. cayetanensis. The sizes of the amplified fragments were 555, 188, and 400 bps, respectively. The multiplex-touchdown PCR protocol using a primer mixture simultaneously detected protozoa in human stools, and the amplified gene was detected in > $1{\times}10^3$ oocysts for C. parvum, > $1{\times}10^4$ cysts for G. lamblia, and > 1 copy of the 18S rRNA gene for C. cayetanensis. Taken together, our protocol convincingly demonstrated the ability to simultaneously detect C. parvum, G. lamblia, and C. cayetanenesis in stool samples.

• Genomics & Informatics
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• 제10권1호
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• pp.9-15
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• 2012

Horizontal gene transfer (HGT) is the movement of genetic material between kingdoms and is considered to play a positive role in adaptation. $Cryptosporidium$ $parvum$ is a parasitic protozoan that causes an infectious disease. Its genome sequencing reported 14 bacteria-like proteins in the nuclear genome. Among them, cgd2_1810, which has been annotated as CysQ, a sulfite synthesis pathway protein, is listed as one of the candidates of genes horizontally transferred from bacterial origin. In this report, we examined this issue using phylogenetic analysis. Our BLAST search showed that $C.$ $parvum$ CysQ protein had the highest similarity with that of proteobacteria. Analysis with NCBI's Conserved Domain Tree showed phylogenetic incongruence, in that $C.$ $parvum$ CysQ protein was located within a branch of proteobacteria in the cd01638 domain, a bacterial member of the inositol monophosphatase family. According to Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, the sulfate assimilation pathway, where CysQ plays an important role, is well conserved in most eukaryotes as well as prokaryotes. However, the Apicomplexa, including $C.$ $parvum$, largely lack orthologous genes of the pathway, suggesting its loss in those protozoan lineages. Therefore, we conclude that $C.$ $parvum$ regained cysQ from proteobacteria by HGT, although its functional role is elusive.

• Parasites, Hosts and Diseases
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• 제34권4호
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• pp.215-224
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• 1996

작은와포자충의 세포골격 단백질 분포를 알아보기 위하여 actin, tropomyosin, $\alpha$-actinin 및 troponin-T의 분포를 이중면역 황금표지법 (double immunogold labeling method)으로 관찰하 였다 관찰된 모든 발육 단계의 충체에서 매우 많은 양의 tropomyosin이 세포질 및 세포막에 분포하고 있음이 밝혀졌으며 actin보다도 더 많은 양이 관찰되었다. ${\alpha}-actinin$의 경우는 주로 세포막에 소량이 분포하였으며 Troponin-T는 어느 발육 단계에서도 관찰되지 않았다 이 연구의 결과 tropomyosin의 분포 정도도 미루어 볼 때 이 단백질이 작은와포자충에서 매우 중요한 역할을 수행할 것으로 추측되며, 주로 세포막에 다량으로 분포하는 actin, tropomyosin 및 ${\alpha}-actinin$은 면역진단 및 면역치료의 대상으로 이용할 가능성이 있을 것으로 생각된다.

• Parasites, Hosts and Diseases
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• 제45권3호
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• pp.225-228
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• 2007

We observed the time gap between oocyst shedding and antibody responses in mice (3-week-old C57BL/6J females) infected with Cryptosporidium parvum. Oocyst shedding was verified by modified acid-fast staining. The individually collected mouse sera were assessed for C. parvum IgM and IgG antibodies by enzyme-linked immunosorbent assay from 5 to 25 weeks after infection. The results showed that C. parvum oocysts were shed from day 5 to 51 post-infection (PI). The IgM antibody titers to C. parvum peaked at week 5 PI, whereas the IgG antibody titers achieved maximum levels at week 25 PI. The results revealed that IgM responses to C. parvum infection occurred during the early stage of infection and overlapped with the oocyst shedding period, whereas IgG responses occurred during the late stage and was not correlated with oocyst shedding. Hence, IgM antibody detection may prove helpful for the diagnosis of acute cryptosporidiosis, and IgG antibody detection may prove effective for the detection of past infection and endemicity.

• Parasites, Hosts and Diseases
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• 제37권1호
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• pp.33-37
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• 1999

An age-dependent aspect of resistance to Cryptosporidium muris (strain MCR) infection was monitored in Syrian golden hamsters. Mesocricetus auratus. at 1-, 5- and 10-week of age and in ICR mice, Mus musculus, at 3-, 12-, and 15-week of age orally inoculated with a single dose of $2{\times}10^6$ oocysts. respectively. The prepatent periods for both animals were similar, independent of age, but the patency was significantly longer in younger hamsters (P<0.001) and a long tendency in younger mice. Hamsters infected at 1-week of age excreted about 10 times higher oocysts than those at 5- and 10-week of age. However, the total oocyst output was similar among mice of different ages. There was a good correlation between the length of the patency and the total oocyst output in hamsters (R=0.9646), but not in mice (R=0.456l). The immunogenicity of the parasite to homologous challenge infections was very strong in hamsters and relatively strong in mice. These results indicate that acquired resistance to C. muris infection is age-related and the innate resistance is independent of age of hamsters, and that both innate and acquired resistance, on the contrary, are irrespective of age of mice.

• Parasites, Hosts and Diseases
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• 제47권1호
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• pp.7-11
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• 2009

Cryptosporidium parvum is a well-known waterborne and opportunistic intracellular protozoan parasite that causes diarrheal illness. In this study, we quantitatively investigated reduction of the infectivity of C. parvum after gamma irradiation and repair of the infectivity during incubation time after irradiation. C. parvum oocysts were subjected to gamma irradiation at various doses (1, 5, 10, and 25 kGy), and the in vitro infectivity was measured by real-time PCR every day up to 7 days after irradiation. The in vitro infectivity of C. parvum on human ileocecal adenocarcinoma cells (HCT-8) was effectively reduced (> $2\;{\log}_{10}$) by irradiation at 10kGy or more. However, in the experiment to find out repair of the infectivity, recovery was not noted until day 7 post-incubation.

• Parasites, Hosts and Diseases
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• 제53권3호
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• pp.335-339
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• 2015

Cryptosporidium andersoni ATP-binding cassette (CaABC) is an important membrane protein involved in substrate transport across the membrane. In this research, the nucleotide binding domain (NBD) of CaABC gene was amplified by PCR, and the eukaryotic expression vector of pEGFP-C1-CaNBD was reconstructed. Then, the recombinant plasmid of pEGFP-C1-CaNBD was transformed into the mouse intestinal epithelial cells (IECs) to study the iron transportation function of CaABC. The results indicated that NBD region of CaABC gene can significantly elevate the transport efficiency of $Ca^{2+}$, $Mg^{2+}$, $K^+$, and $HCO_3{^-}$ in IECs (P<0.05). The significance of this study is to find the ATPase inhibitors for NBD region of CaABC gene and to inhibit ATP binding and nutrient transport of CaABC transporter. Thus, C. andersoni will be killed by inhibition of nutrient uptake. This will open up a new way for treatment of cryptosporidiosis.