Tissues Of Infected Animals Research Articles

An experimental challenge model of visceral leishmaniasis by Leishmania donovani promastigotes in mice

Although visceral leishmaniasis is a fatal disease in humans and dogs, the use of mouse models is important for obtaining a better understanding of the pathogenesis, immunity, and host–parasite interactions of this disease. Such models are also useful for the evaluation of vaccines and chemotherapies for treatment of visceral leishmaniasis. Here, we present our method of experimental inoculation of mice with Leishmania donovani promastigotes. Nutrient-enriched undefined media may be beneficial for laboratory maintenance of promastigotes for maintaining their virulence or infectivity in mice. With this method, we could preserve the infectivity of promastigote lines recovered from inoculated animals and use these lines for further in vivo experiments. Furthermore, the use of cryopreserved stabilates is highly recommended for the reproducibility of experiments. To assess a newly developed method for determination of parasite burden in infected animal tissues, initial comparison of parasite burden in the liver obtained in the classic Leishman-Donovan units (LDU) with values obtained from the new method is recommended. As an example, the association between parasite burden determined by LDU and real-time PCR assay targeting the leishmanial gp63 gene in the liver of mice is presented.

Optimization of Process Conditions for Infected Animal Tissues by Alkaline Hydrolysis Technology

Alkaline hydrolysis represents a relatively new animal carcass disposal technology. It uses alkali, high temperature and high pressure to catalyze the hydrolysis of biological materials into a sterile aqueous solution and bone residues. The purpose of this work is to provide a complete study of the influence of operational parameters on alkaline hydrolysis process and to find an optimal combination of factors that maximize the disposal efficiency. In order to determine the optimal combination of the four factors viz. treatment time, temperature, the concentration of alkali solution and the ratio of alkali and tissue, single-factor and orthogonal experiments were used. The orthogonal experimental design included four variables (three levels) in L9 orthogonal array. Results showed that four factors all significantly (P < 0.01) increased the efficiency of alkaline hydrolysis. The order of significance decreased from temperature, alkali concentration, the ratio of alkali and tissue to treatment time. Optimum process conditions were found to be as follows: treatment time, 180min; temperature, 150°C; the concentration of alkali solution, 5% and the ratio of alkali and tissue, 3mL/g. The optimum conditions was validated and proven to be reliable for achieving the complete hydrolysis of different animal tissues and the inactivation of Bacillus stearothermophilus. This study provides a biosafety disposal method of infected animal tissues and be useful to establish effective process conditions of alkaline hydrolysis.

Application of Molecular Techniques to understand Pathogenesis of Equine Herpes Virus 9 (EHV-9) In Pregnant Hamsters

In the present study we tried to understand pathogenesis of equine herpes virus 9 (EHV-9) in pregnant animals through experimental infection of early and late pregnant Syrian hamsters which is considered the ideal experimental model for equidae. We described the clinical manifestations and tracked the viral load in different maternal tissues including blood, brain, uterus and placenta by using the absolute quantification technique of real time PCR. The viral load was expressed as the number of EHV-9 ORF30 gene copies and standardized against the house keeping hamster GAPDH gene. The viral load in the blood increased significantly at 6th day post infection regardless stage of infection, while it increased gradually in the brain tissue to reach maximum levels at late stages of pregnancy. In the other hand, the viral load in the uterine and placental tissues increased significantly in late trimester infected group than early trimester infected group. Clinical signs appeared on experimentally infected hamsters were very similar to that appeared in equines due to EHV-1 infection and it synchronically correlated to the viral load in different tissues. On the basis of our results we can conclude that clinical manifestations of EHV-9 are very similar to that of EHV-1 and its appearance is correlated to the increased viral multiplication in blood, brain, uterus and placental tissues of the infected animal.

The Occupational Opportunist: an Update on Erysipelothrix rhusiopathiae Infection, Disease Pathogenesis, and Microbiology

The genus Erysipelothrix currently consists of four named species, the most clinically significant of which is E. rhusiopathiae. E. rhusiopathiae is found ubiquitously in the environment, with worldwide prevalence. The organism is identified as both a pathogen and a saprophyte for diverse hosts, ranging from fish and amphibians to birds, mammals, and insects. E. rhusiopathiae is recognized as the etiological agent of swine erysipelas, a disease of significant economic consequence. Human clinical infections are generally the result of occupational zoonotic exposure to infected animal tissues or by-products. Although rare, three distinct clinical forms of human E. rhusiopathiae disease are recognized: a localized cutaneous cellulitis (human erysipeloid), a disseminated cutaneous infection, and an infectious endocarditis that is usually secondary to sepsis. Diagnosis of E. rhusiopathiae infection can be complicated, particularly with limited clinical history; therefore, the microbe may be under-recognized. From a laboratory perspective, diagnostic challenges include the bacterium's Gram stain variability and variable cellular and colony morphologies that can occur during identification. While the disease is treatable with routine antimicrobials, empiric therapeutic interventions can be hampered due to intrinsic vancomycin resistance. The recent availability of the E. rhusiopathiae genome will strengthen our understanding of the organism's disease pathogenesis and expand our knowledge about the spectrum of E. rhusiopathiae infections.

Toxoplasma gondii in wild ruminants bred in game preserves and farms with production destined for human consumption in the Czech Republic.

Toxoplasma gondii is the causative agent of the most common parasitic infection in humans. Almost all warm-blooded animals, as well as humans, can act as intermediate hosts that harbour infective cysts in their tissues. Felids act as definitive hosts excreting oocysts in faeces. In humans, T. gondii can cause subclinical infection but also severe clinical disease with a wide range of symptoms, especially in immunocompromised individuals. The infection is usually asymptomatic in animals and is not recognized at either ante- or post-mortem inspection. The consumption of undercooked meat from infected animals is one of the most important routes by which the infection can be transmitted to humans. Handling of the organs and other tissues of game animals and eating their undercooked meat have been described as a risk of T. gondii infection. For diagnosis of toxoplasmosis, the combination of serological and molecular methods has been described as a suitable approach. Antibodies against T. gondii were detected in 20.8%, 50.0%, 23.1%, and 24.4% of red deer, sika deer, fallow deer and mouflons, respectively, coming from game preserves and farms in the Czech Republic. T. gondii DNA was found in the muscle tissue of red deer (8.3%) and mouflons (14.6%). The lower prevalence rates based on molecular screening could be due to the random distribution and low density of cysts in tissues of infected animals. Bearing in mind the increase in the number of hunted animals and the growing trend in game consumption, it is important to educate hunters and game meat consumers about the risk of exposure to this zoonotic infection during handling and consumption of the meat.

Quantitative detection of Toxoplasma gondii in tissues of experimentally infected turkeys and in retail turkey products by magnetic-capture PCR

Magnetic-capture PCR was applied for the quantitative detection of Toxoplasma gondii in tissues of experimentally infected turkeys and retail turkey meat products. For experimental infection, three T. gondii strains (ME49, CZ-Tiger, NED), varying infectious doses in different matrices (organisms in single mouse brains or 103, 105, or 106 oocysts in buffer) were used. From all animals, breast, thigh, and drumstick muscle tissues and for CZ-Tiger-infected animals additionally brains and hearts were analyzed. Using the magnetic-capture PCR large volumes of up to 100 g were examined. Our results show that most T. gondii parasites are present in brain and heart tissue. Of the three skeletal muscle types, drumsticks were affected at the highest and breast at the lowest level. Type III strain (NED) seems to be less efficient in infecting turkeys compared to type II strains, because only few tissues of NED infected animals contained T. gondii DNA. Furthermore, the number of detected parasitic stages increased with the level of infectious dose. Infection mode by either oocyst or tissue cyst stage did not have an effect on the amount of T. gondii present in tissues. In retail turkey meat products T. gondii DNA was not detectable although a contact with the parasite was inferred by serology.

Inflammation in the Pathogenesis of Lyme Neuroborreliosis

Lyme neuroborreliosis, caused by the spirochete Borrelia burgdorferi, affects both peripheral and central nervous systems. We assessed a causal role for inflammation in Lyme neuroborreliosis pathogenesis by evaluating the induced inflammatory changes in the central nervous system, spinal nerves, and dorsal root ganglia (DRG) of rhesus macaques that were inoculated intrathecally with live B. burgdorferi and either treated with dexamethasone or meloxicam (anti-inflammatory drugs) or left untreated. ELISA of cerebrospinal fluid showed significantly elevated levels of IL-6, IL-8, chemokine ligand 2, and CXCL13 and pleocytosis in all infected animals, except dexamethasone-treated animals. Cerebrospinal fluid and central nervous system tissues of infected animals were culture positive for B. burgdorferi regardless of treatment. B. burgdorferi antigen was detected in the DRG and dorsal roots by immunofluorescence staining and confocal microscopy. Histopathology revealed leptomeningitis, vasculitis, and focal inflammation in the central nervous system; necrotizing focal myelitis in the cervical spinal cord; radiculitis; neuritis and demyelination in the spinal roots; and inflammation with neurodegeneration in the DRG that was concomitant with significant neuronal and satellite glial cell apoptosis. These changes were absent in the dexamethasone-treated animals. Electromyography revealed persistent abnormalities in F-wave chronodispersion in nerve roots of a few infected animals; which were absent in dexamethasone-treated animals. These results suggest that inflammation has a causal role in the pathogenesis of acute Lyme neuroborreliosis.

Experimental susceptibility of European sea bass and Senegalese sole to different betanodavirus isolates

The susceptibility of juvenile European sea bass and Senegalese sole to three VNNV isolates (a reassortant RGNNV/SJNNV, as well as the parental RGNNV and SJNNV genotypes) has been evaluated by challenges using two inoculation ways (bath and intramuscular injection). The results demonstrate that these two fish species are susceptible to all the VNNV isolates tested. In European sea bass, RGNNV caused the highest cumulative mortality, reaching maximum values of viral RNA and titres. Although the SJNNV isolate did not provoke mortality or clinical signs of disease in this fish species, viral production in survivor fish was determined; on the other hand the reassortant isolate did cause mortality and clinical signs of disease, although less evident than those recorded after RGNNV infection. These results suggest that the changes suffered by the SJNNV RNA2 segment of the reassortant isolate, compared to the parental SJNNV, may have involved host-specificity and/or virulence determinants for European sea bass. Regarding Senegalese sole, although the three isolates caused 100% mortality, the reassortant strain provoked the most acute symptoms, and more quickly, especially in the bath challenge. This was also the isolate showing less difference between the number of RNA copies and viral titre, reaching the highest titres of infective viral particles in nervous tissue of infected animals. The RGNNV isolate produced the lowest values of infective viral particles. All these results suggest that the RGNNV and the reassortant isolates are the most suited for infecting European sea bass and Senegalese sole, respectively.

Crimean-Congo hemorrhagic fever and pregnancy: Two cases

Crimean-Congo Hemorrhagic Fever (CCHF) is a viral zoonosis, transmitted to humans by either: the Hyalomma species of ticks; or by direct contact with body fluids or tissues of infected humans or domestic animals. CCHF can result in death through clinical progression of hemorrhagic fever (1). Tokat Province in Turkey is where CCHF cases are seen at the highest rate. In this article, the cases of two pregnant women are discussed. The women applied in Tokat with a fever and were diagnosed with CCHF. Along with symptomatic treatment, thrombocyte and fresh frozen plasma replacement was performed in one of the patient’s cases. Patients were discharged with recovery. The main purpose of this article is to enlighten the progression of CCHF during pregnancy. J Microbiol Infect Dis 2015;5(1): 29-31

Dysbiotic bacteria translocate in progressive SIV infection.

Infection of gut-resident CD4+ memory T-cells during acute HIV and SIV infection is associated with rapid loss of these cells and damage to the epithelial barrier. Damage to the epithelial barrier allows translocation of microbial products from the intestinal lumen into the body. Immune activation caused by these microbial products has been associated with disease progression. Although microbial translocation has been demonstrated in SIV-infected nonhuman primates, the identity of translocating bacteria has not been determined. In this study we examined the communities of bacteria both within the GI tract and systemic tissues of both healthy and experimentally SIV-infected Asian macaques. While there were only modest changes in the GI tract-associated microbiome resulting from infection, there is substantial dysbiosis after administration of antiretrovirals. Analysis of bacterial DNA isolated from tissues of infected animals revealed a preference for the phylum Proteobacteria, suggesting that they preferentially translocate. Consistent with this finding, we observed increased metabolic activity of Proteobacterial species within the colonic lumen of SIV-infected animals. Overall these data provide insights into disease progression and suggest that therapies aimed at altering the composition and metabolic activity of the GI tract microbiome could benefit chronically-HIV infected individuals particularly those on antiretroviral therapies.

Identification of snake arenaviruses in live boas and pythons in a zoo in Germany.

Recent studies have described the detection and characterisation of new, snake specific arenaviruses in boas and pythons with inclusion body disease (IBD). The objective of this study was to detect arenaviral RNA in live snakes and to determine if these were associated with IBD in all cases. Samples for arenavirus detection in live animals were compared. Detected viruses were compared in order to understand their genetic variability. Esophageal swabs and whole blood was collected from a total of 28 boas and pythons. Samples were tested for arenaviral RNA by RT-PCR. Blood smears from all animals were examined for the presence of inclusion bodies. Internal tissues from animals that died or were euthanized during the study were examined for inclusions and via RT-PCR for arenaviral RNA. All PCR products were sequenced and the genomic sequences phylogenetically analysed. Nine live animals were found to be arenavirus-positive. Two additional snakes tested positive following necropsy. Five new arenaviruses were detected and identified. The detected viruses were named "Boa Arenavirus Deutschland (Boa Av DE) numbers 1-4" and one virus detected in a python (Morelia viridis) was named "Python Av DE1". Results from sequence analyses revealed considerable similarities to a portion of the glycoprotein genes of recently identified boid snake arenaviruses. Both oral swabs and whole blood can be used for the detection of arenaviruses in snakes. In most cases, but not in all, the presence of arenaviral RNA correlated with the presence of inclusions in the tissues of infected animals. There was evidence that some animals may be able to clear arenavirus infection without development of IBD. This is the first detection of arenaviruses in live snakes. The detection of arenaviruses in live snakes is of importance for both disease detection and prevention and for use in quarantine situations. The findings in this study support the theory that arenaviruses are the cause of IBD, but indicate that in some cases it may be possible for animals to clear arenavirus infections without developing IBD.

Virus-specific immune memory at peripheral sites of herpes simplex virus type 2 (HSV-2) infection in guinea pigs.

Despite its importance in modulating HSV-2 pathogenesis, the nature of tissue-resident immune memory to HSV-2 is not completely understood. We used genital HSV-2 infection of guinea pigs to assess the type and location of HSV-specific memory cells at peripheral sites of HSV-2 infection. HSV-specific antibody-secreting cells were readily detected in the spleen, bone marrow, vagina/cervix, lumbosacral sensory ganglia, and spinal cord of previously-infected animals. Memory B cells were detected primarily in the spleen and to a lesser extent in bone marrow but not in the genital tract or neural tissues suggesting that the HSV-specific antibody-secreting cells present at peripheral sites of HSV-2 infection represented persisting populations of plasma cells. The antibody produced by these cells isolated from neural tissues of infected animals was functionally relevant and included antibodies specific for HSV-2 glycoproteins and HSV-2 neutralizing antibodies. A vigorous IFN-γ-secreting T cell response developed in the spleen as well as the sites of HSV-2 infection in the genital tract, lumbosacral ganglia and spinal cord following acute HSV-2 infection. Additionally, populations of HSV-specific tissue-resident memory T cells were maintained at these sites and were readily detected up to 150 days post HSV-2 infection. Unlike the persisting plasma cells, HSV-specific memory T cells were also detected in uterine tissue and cervicothoracic region of the spinal cord and at low levels in the cervicothoracic ganglia. Both HSV-specific CD4+ and CD8+ resident memory cell subsets were maintained long-term in the genital tract and sensory ganglia/spinal cord following HSV-2 infection. Together these data demonstrate the long-term maintenance of both humoral and cellular arms of the adaptive immune response at the sites of HSV-2 latency and virus shedding and highlight the utility of the guinea pig infection model to investigate tissue-resident memory in the setting of HSV-2 latency and spontaneous reactivation.

Patogenicidade e virulência de Toxoplasma gondii isolado de suínos de criação artesanal no sul do Brasil

Estudos com Toxoplasma gondii em suínos são relevantes porque seus produtos e subprodutos fazem parte da cadeia alimentar do ser humano. As principais vias de transmissão deste agente são o carnivorismo, fecal-oral e congênita. Seis isolados de Toxoplasma gondii de suínos de criação artesanal foram avaliados quanto à patogenicidade e virulência em camundongos suíços albinos. A suspensão de taquizoítos utilizada nos testes foi obtida através da punção ou lavagem da cavidade peritoneal de camundongos que apresentaram ascite. Cada amostra foi inoculada em grupos de cinco camundongos, com inóculo de 10¹, 10², 10³, 10(4), 10(5) e 10(6) taquizoítos vivos, via intraperitoneal. Dos isolados, 50% (3/6) foram letais e causaram sinais clínicos nos camundongos. A dose mínima letal foi de 10³ taquizoítos. A morte dos animais que apresentaram infecção aguda ocorreu entre 12 e 26 dias após a inoculação. Todos os isolados da região estudada apresentam alta capacidade de formar cistos, o que pode aumentar o risco de infecção pela ingestão de tecidos dos animais infectados pelos mesmos.

Genome-Wide Mutant Fitness Profiling Identifies Nutritional Requirements for Optimal Growth of Yersinia pestis in Deep Tissue

ABSTRACTRapid growth in deep tissue is essential to the high virulence of Yersinia pestis, causative agent of plague. To better understand the mechanisms underlying this unusual ability, we used transposon mutagenesis and high-throughput sequencing (Tn-seq) to systematically probe the Y. pestis genome for elements contributing to fitness during infection. More than a million independent insertion mutants representing nearly 200,000 unique genotypes were generated in fully virulent Y. pestis. Each mutant in the library was assayed for its ability to proliferate in vitro on rich medium and in mice following intravenous injection. Virtually all genes previously established to contribute to virulence following intravenous infection showed significant fitness defects, with the exception of genes for yersiniabactin biosynthesis, which were masked by strong intercellular complementation effects. We also identified more than 30 genes with roles in nutrient acquisition and metabolism as experiencing strong selection during infection. Many of these genes had not previously been implicated in Y. pestis virulence. We further examined the fitness defects of strains carrying mutations in two such genes—encoding a branched-chain amino acid importer (brnQ) and a glucose importer (ptsG)—both in vivo and in a novel defined synthetic growth medium with nutrient concentrations matching those in serum. Our findings suggest that diverse nutrient limitations in deep tissue play a more important role in controlling bacterial infection than has heretofore been appreciated. Because much is known about Y. pestis pathogenesis, this study also serves as a test case that assesses the ability of Tn-seq to detect virulence genes.

A Five-Member Family With Crimean-Congo Hemorrhagic Fever; A Case Series Study

Introduction: Crimean-Congo Hemorrhagic fever (CCHF) is a viral hemorrhagic fever which transmitted by tick-bites, or through contact with infected animal tissues or secretions during and immediately post-slaughter. It can be responsible for severe outbreaks in humans. Case Presentation: We have explained five patients of a family with (CCHF), which acquired the illness at one time. Every five patients were admitted to our hospital and they treated by ribavirin promptly. Unfortunately, one patient was referred late to the hospital and the treatment started 96 hours after the beginning of the first sign who expired Conclusions: CCHFV can infect human clustering in a family .To our knowledge, this is the first report of this form in Iran.

Complete genome sequence and pathogenesis of bovine viral diarrhea virus JL-1 isolate from cattle in China

BackgroundBovine viral diarrhea virus (BVDV) is a pathogen found worldwide in calves. It can cause significant economic losses in agriculture. Many BVDV strains have been isolated in China. However, the pathogenesis and complete gene characteristics of BVDV isolate have yet not been reported in China. Here, a BVDV isolate was isolated and its pathogenesis and complete genome were studied.ResultsA new isolate of bovine viral diarrhea virus, named JL-1, was isolated from the spleen of a sick cow with diarrhea using MDBK cell culture. The complete genome of JL-1 is 12,276 nucleotides and contains a 5′-UTR of 382 nucleotides, a 3′-UTR of 188 nucleotides, and a large ORF encoding a polyprotein consisting of 3,901 amino acids. Genomic comparison and phylogenetic analyses of complete genomic sequence clearly showed that JL-1 fell into the BVDV-1b subtype. The result of pathogenesis of JL-1 strain showed that all infected calves developed clinical signs of elevated rectal temperatures, decreased leucopenia, and viral discharge. Viral antigen was detected in infected animal tissues using immunohistochemistry. Animals in the mock were normal. These results demonstrated that BVDV JL-1 was a virulent strain.ConclusionsThis is the first study to report the pathogenesis and complete gene characterization of the BVDV strain in China. This report may set a good foundation for further study of BVDV in China.

Validation of a real time PCR for classical Swine Fever diagnosis.

The viral disease classical swine fever (CSF), caused by a Pestivirus, is one of the major causes of economic losses for pig farming. The aim of this work was to validate a RT-qPCR using Taqman for detection of CSF in swine tissues. The parameters for the validation followed the specifications of the Manual of Diagnostic Tests and Vaccines for Terrestrial Animals of the World Organization for Animal Health (OIE) and the guide ABNT NBR ISO/IEC 17025:2005. The analysis of the 5′NTR region of CSF virus was performed in 145 samples from 29 infected pigs and in 240 samples from 80 pigs originated in the Brazilian CSF-free zone. The tissues tested were spleen, kidney, blood, tonsils, and lymph nodes. Sequencing of the positive samples for 5′NTR region was performed to evaluate the specificity of the RT-qPCR. Tests performed for the RT-qPCR validation demonstrated that the PCR assay was efficient in detecting RNA from CSF virus in all materials from different tissues of infected animals. Furthermore, RNA from CSF virus was not detected in samples of swine originated from the Brazilian CSF-free zone. Hence, it is concluded that RT-qPCR can be used as a complementary diagnostic for CSF.

Control the activity of Rift Valley Fever Virus by Electric Field waves at resonance frequency (In vivo &amp;In vitro) studies

Rift valley fever virus (RVFV) causes severe disease, abortion and deaths in domestic animals (especially) young sheep, cattle and goats humans are infected by this virus through mosquitoes which maintain epizootic transmission being in contact with infected animal tissue. For this purpose, RVFV activities in Vero cell line media were exposed to different frequencies of amplitude modulated (AM) waves in the frequency range ( from 1 Hz to 10 Hz) for a period of 30 minutes /day along four successive days no measurable effect of the square amplitude modulated waves (QAMW) was noticed after the experiment in the Vero-cells. In another experiment 48 female Bulb/C mice were equally divided into 6 groups namely A1, A2, A3, A4, A5 & negative control.A1, A4 & A5 animals were infected by injection intraperitoneal (i.p) with dose of RVFV (0.15 mg/ Kg body weight (b.w) . A4 &A5 were exposed for 30 minutes /day along four successive days to 4.4 Hz & 5.2 Hz respectively while A1 without treatment any further treatment .A2 & A3 animals were exposed to 4.4 Hz & 5.2 Hz respectively for 30 minutes /day along four successive days, control group were injected 100 µl of saline by (i.p). At day 28 post injection of the animal, blood was collected for each group then after at sacrifice the liver enzymes (SGPT&SGOT),cellular changes were evaluated using cytokines expression (IFN- γ & IL-5) the exposed and non exposed ELF were studied survival rate and histopathology were demonstrated. The results: In vitro the data highly significant growth enhancement & inhibition respectively occurred in RVFV injected with vero cells after exposure to 4.4 Hz& 5.2 Hz respectively QAMW for 30 minutes/day along four successive days. In vivo the groups A1, A2&A3 highly significant increase in the serum level of SGPT&SGOT by less than A4&A5 groups respectively .The groups A2 &A3 were a significant increase in the serum level of IFN-γ. While, the serum level of IFN-γ of groups A1, A4 and A5 exhibited a significant decrease .Where the results were slightly increase but non-significant in level of IL-5 production in serum in groups A2 and A3. While the level of IL-5 of group A1 were a highly significant suppression more than in the groups A4 &A5 when compared to control. Histological sections of the exposed and non exposed were studied and survival rate were demonstrated.

Immunohistopathology of Prototheca wickerhamii in Cutaneous Lesions of Protothecosis

Protothecosis is a rare infection caused by pathogenic algae of the genus Prototheca. Prototheca wickerhamii causes cutaneous/subcutaneous opportunistic infections in humans and small animals. The diagnosis of protothecosis is based on histopathological examination of this organism, which can be confused with other fungi and inflammatory cells in infected tissues. In this study, immunohistopathological investigation was made of infected cutaneous human and animal tissues exhibiting protothecosis using rabbit antiserum against P. wickerhamii. Serum detected P. wickerhamii in human and feline protothecosis tissues, and did not react with Candida albicans in the human kidney tissues showing candidiasis. This antiserum can therefore differentiate P. wickerhamii cells from the yeast-like cells of C. albicans and Prototheca zopfii in target tissues.

Use of IgY antibody to recombinant avian reovirus σC protein in the virus diagnostics

Avian reovirus (ARV) is an important agent of several diseases causing considerable losses in poultry farming. An outer capsid protein (σC) of ARV, is known as a virus-cell attachment protein essential for virus infectivity. In this study, the σC gene of ARV was cloned and expressed in Escherichia coli. The expressed recombinant protein was used as immunogen for raising a specific IgY antibody in laying hens. At 14 weeks post immunization, the antibody titers in serum and egg yolk reached 302,000 and 355,000, respectively. The IgY antibody was capable to neutralize ARV in BHK-21 cells and it strongly reacted in ELISA with ARV but not with heterologous viruses. The IgY antibody detected ARV in field samples of infected animal tissues in dot blot assay. These results suggest that an efficient, economic and rapid diagnostics of ARV can be performed routinely using the IgY antibody against a recombinant ARV σC protein.