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Molecular Tools for Nucleic Acid AnalysisO'Meara, Deirdre January 2001 (has links)
<p>Nucleic acid technology has assumed an essential role invarious areas of<i>in vitro</i>diagnostics ranging from infectious diseasediagnosis to human genetics. An important requirement of suchmolecular methods is that they achieve high sensitivity andspecificity with a fast turnaround time in a cost-effectivemanner. To this end, in this thesis we have focused on thedevelopment of sensitive nucleic acid strategies thatfacilitate automation and high-throughput analysis.</p><p>The success of nucleic acid diagnostics in the clinicalsetting depends heavily on the method used for purification ofthe nucleic acid target from biological samples. Here we havefocused on developing strategies for hybridisation capture ofsuch templates. Using biosensor technology we observed that thehybridisation efficiency could be improved using contiguousoligonucleotide probes which acted co-operatively. Byimmobilising one of the probes and annealing the second probein solution, we achieved a marked increase in target capturedue to a base stacking effect between nicked oligonucleotidesand/or due to the opening up of secondary structure. Suchco-operatively interacting modular probes were then combinedwith bio-magnetic bead technology to develop a capture systemfor the extraction of hepatitis C RNA from serum. Viral capturewith such co-operatively interacting probes extracted 2-foldmore target as capture with only a single probe achieving asimilar sensitivity to the conventional extraction protocol. Ananalogous strategy was designed to enrich for sequencingproducts prior to gel electrophoresis removing sequencingreagents and template DNA which interfere with the separationand detection of sequencing ladders, especially in the case ofcapillary gel electrophoresis. This protocol facilitates highthroughput clean-up of cycle sequencing reactions resulting inaccurate sequence data at a low cost, which is a pre-requisitefor large-scale genome sequencing products.</p><p>Currently, a large effort is directed towards differentialsequencing to identify mutations or polymorphisms both in theclinical laboratory and in medical genetics. Inexpensive, highthroughput methods are therefore required to rapidly screen atarget nucleic acid for sequence based changes. In the clinicalsetting, sequence analysis of human immunodeficiency virus(HIV-1) is used to determine the presence of drug resistancemutations. Here we describe a bioluminometric pyrosequencingapproach to rapidly screen for the presence of drug resistancemutations in the protease gene of HIV-1. This sequencingstrategy can analyse the protease gene of HIV-1 from eightpatients in less than an hour and such non-gel based approachesshould be useful in the future in a clinical setting for rapid,robust mutation detection.</p><p>Microarray technology facilitates large-scalemutation/polymorphism detection and here we developed amicroarray based single nucleotide polymorphism (SNP)genotyping strategy based on apyrase mediated allele specificextension (AMASE). AMASE exploits the fact that mismatchedprimers exhibit slower reaction kinetics than perfectly matchedprimers by including a nucleotide degrading enzyme (apyrase)which results in degradation of the nucleotides before themismatched primer can be extended. We have successfully typed200 genotypes (14% were incorrect without apyrase) by AMASEwhich cluster into three distinct groups representing the threepossible genotypes. In the future, AMASE on DNA microarraysshould facilitate association studies where an accuracy>99%is required.</p><p><b>Keywords:</b>nucleic acid capture, modular probes,biosensor, bio-magnetic separation, hepatitis C, sequencing,pyrosequencing, mutation detection, HIV-1, drug resistance,SNP, allele-specific extension, apyrase, genotyping.</p>
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Detection of QTL affecting flesh quality traits (body lipid percentage and flesh colour) using molecular markers (microsatellites and AFLP markers) in Atlantic salmon (Salmo salar L.)Derayat, Amid January 2009 (has links)
Flesh colour and fillet fat percentage are the two most important attributes to salmon fillet quality. A medium genetic component to body lipid percentage within commercial lines has previously been shown (h2 = 0.17-0.24). A low level of heritability (h2 = 0.16) has also been reported for flesh colour in Atlantic salmon. To investigate whether this genetic component includes loci of major effect, a genome-wide QTL scan was performed with commercially bred Atlantic salmon (Landcatch Natural Selection). Five large full-sib families (10 parents with 153 offspring) were genotyped using microsatellite markers. To utilize the large difference between sire and dam recombination rate, a two-stage genotyping was employed. Initially, the parents and offspring were genotyped for two microsatellite markers per linkage group, and sire based QTL analysis was used to detect linkage groups with significant effects on those flesh quality traits. A linear-regression based interval as analytical method was applied for QTL detection. The results revealed evidence of QTLs affecting percentage fat percentage and flesh colour on linkage groups LNS16 and LNS1 respectively. To confirm the QTL and to provide an improved estimate of position, a dam-based analysis was then employed. One major QTL was located on the genome-wide significance level for percentage fat percentage. Microsatellite marker Ssa0016NVH (at position of 1.3 cM) was found to be tightly linked to QTL affecting percentage fat percentage. In addition, a QTL affecting flesh colour was found to be flanked by microsatellite markers Ssa9.44NUIG at position of 68.7 cM and Ssa0021NVH at position of 50.6 on linkage group LNS16. The evidence for suggestive QTL affecting flesh colour on linkage group LNS1 was also revealed. In order to increase marker density within these and other linkage groups, AFLP markers were employed, 24 primer combinations resulted in a total of 489 polymorphic fragments. Among 11 fragments that were found to be linked to the microsatellite markers on linkage group LNS16, four fragments (AAG-CAC328, AGG-CAG447, AGG-CTA237 and AGG-CTC237) were tightly linked to microsatellite marker Ssa9.44NUIG, but none were found to be linked to microsatellite Ssa0021NVH. Moreover, none of the AFLP markers were found to be linked to microsatellites residing on linkage group LNS1. Using a constructed map of microsatellite and AFLP markers for linkage group LNS16, the dam based analysis revealed a significant QTL for flesh colour at the location of 189 cM, while the sire based analysis detected a significant QTL for fat percentage at the location of 80 cM. Considering the dominant nature and clustering character of AFLP markers, it was concluded that a certain primer combination in AFLP markers could be of limited use for fine mapping and QTL detection in Atlantic salmon.
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Étude de la diversité génétique d’isolats québécois de Mycoplasma hyopneumoniae provenant d’infections simples ou mixtes et caractérisation de leur sensibilité aux antimicrobiensCharlebois, Audrey 12 1900 (has links)
Mycoplasma hyopneumoniae est l’agent causal de la pneumonie enzootique. On le retrouve dans plusieurs élevages de porcs à travers le monde. Même si ce micro-organisme est présent dans plusieurs troupeaux canadiens, peu d’informations sont présentement disponibles sur les isolats québécois. Un total de 160 poumons de porcs possédant des lésions de pneumonie ont été récupérés à l’abattoir, mis en culture et testés par PCR pour M. hyopneumoniae et Mycoplasma hyorhinis. D’autres pathogènes bactériens communs du porc et les virus du syndrome reproducteur et respiratoire porcin (VSRRP), de l’influenza et le circovirus porcin de type 2 (CVP2) ont été également testés. Quatre-vingt-dix pourcent des échantillons étaient positifs pour M. hyopneumoniae et 5.6% l’étaient seulement pour M. hyorhinis. Dans ces échantillons positifs pour M. hyopneumoniae, la concentration de ce mycoplasme variait de 1.17 x 105 à 3.37 x 109 génomes/mL. Vingt-cinq poumons positifs en culture ou par PCR en temps réel pour M. hyopneumoniae ont été sélectionnés, parmi ceux-ci 10 étaient en coinfection avec Pasteurella multocida, 12 avec Streptococcus suis, 9 avec CVP2 et 2 avec le VSRRP. Les analyses des nombres variables de répétitions en tandem à de multiples loci (MLVA) et PCR-polymorphisme de longueur de fragments de restriction (PCR-RFLP) de M. hyopneumoniae ont démontré une forte diversité des isolats de terrain. Par contre, il semble y avoir plus d’homogénéité à l’intérieur d’un même élevage. L’analyse MLVA a également démontré que près de la moitié des isolats possédaient moins de 55% d’homologie avec les souches vaccinales et de référence utilisées dans la présente étude. L’absence d’amplification du locus 1 de M. hyopneumoniae en MLVA a été significativement associée à une baisse de la concentration de bactérie et de la sévérité des lésions. Pour tous les isolats de M. hyopneumoniae, des concentrations minimales inhibitrices (CMI) de faibles à intermédiaires ont été obtenues envers tous les antimicrobiens testés. Les isolats possédant des CMI intermédiaires envers les tétracyclines, les macrolides et les lincosamides ont été testés pour la présence des gènes de résistance tetM, ermB et pour des mutations ponctuelles dans les gènes des protéines L4, L22 et de l’ARNr 23S. Aucun de ces gènes n’a été détecté mais la mutation ponctuelle G2057A a été identifiée. Cette mutation est responsable de la résistance intrinsèque de M. hyopneumoniae face aux macrolides à 14 carbones. Ces résultats indiquent qu’il ne semble pas y avoir de résistance acquise aux antimicrobiens parmi ces isolats. En conclusion, cette recherche a permis d’obtenir de nouvelles données scientifiques sur les isolats québécois de M. hyopneumoniae. / Mycoplasma hyopneumoniae, the causative agent of porcine enzootic pneumonia, is present in swine herds worldwide. However, little is known about the prevalence of this microorganism in Quebec and Canadian herds. A total of 160 swine lungs with lesions suggestive of enzootic pneumonia were recovered from two slaughterhouses. They were cultured and tested by PCR for M. hyopneumoniae and Mycoplasma hyorhinis and for the porcine reproductive and respiratory syndrome virus (PRRSV), the influenza virus, and the porcine circovirus type 2 (PCV2). Samples were also cultured for other commonly encountered swine pathogenic bacteria. Ninety percent of the samples were positive for M. hyopneumoniae (Real-time PCR) whereas 5.6% were positive only for M. hyorhinis (PCR). The concentration of M. hyopneumoniae in these positive samples varied between 1.17 x 105 and 3.37 x 109 genomes/mL Among 25 selected M. hyopneumoniae positive lungs (culture or real-time PCR), 10 demonstrated a co-infection with Pasteurella multocida, 12 with Streptococcus suis, 9 with PCV2 and 2 with the PRRS virus. Multiple loci variable number of tandem repeats analysis (MLVA) and PCR-restriction fragments length polymorphism (PCR-RFLP) analyses showed a high diversity among field M. hyopneumoniae isolates. However, there seemed to be greater homogeneity within the same herd. The MLVA analysis also demonstrated that almost half of the field isolates presented less than 55% homology with the vaccine and reference strains used in our study. The absence of amplification of one locus (locus 1) of M. hyopneumoniae was significantly associated with a lower number of bacteria and a lower severity of lung lesions. All M. hyopneumoniae isolates showed low to intermediate MICs against the antimicrobials tested. Cultures with intermediate MICs for tetracyclines, macrolides and lincosamides were tested for the presence of previously described resistance genes tetM, ermB and L4, L22 and 23S rRNA point mutations. None of these genes were found, although one point mutation, G2057A, was identified. This mutation is responsible for the intrinsic resistance of M. hyopneumoniae against 14-membered macrolides. These results indicate that there is probably no acquired antimicrobial resistance within these isolates. This research provides new scientific data on M. hyopneumoniae isolates from Canada.
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Development of Y-STR genotyping systems suitable for sexual assault cases in South Africa.Cloete, Kevin Wesley. January 2010 (has links)
<p>Sexual assault is a significant problem facing the South African society. In this context, efficient but also affordable genotyping systems are needed for positive identification of criminals in incidences of sexual violence. The aim of this study was therefore to develop non-commercial Y-STR genotyping systems suitable for sexual assault cases in South Africa. Y-chromosome STR loci constituting the minimal haplotype are still the most widely used loci in investigating sexual assault cases despite the fact that DYS391 and DYS392 have shown low levels of polymorphism in Xhosa populations in Cape Town. The minimal haplotype was, therefore, further investigated in the Cape Muslim population. The Cape Muslim population generally exhibited high GD values among all the South African populations. These values were higher than 0.5 for most loci, and ranged from 0.447 for DYS391 to 0.957 for DYS385. The highest number of alleles in most loci was also recorded in this population. The overall assessment of the minimal haplotype has shown that this system is still a useful in investigating sexual assault case in many South African subpopulations. Therefore the exercise of internal validation of the minimal haplotype system was successfully carried out in the laboratory. iii The properties of additional novel and widely used STRs were also investigated in this study. Loci were successfully sequenced and allele nomenclature was assigned to them according to the ISFG guidelines.</p>
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Forensic identification of six of Tanzanian populations using the extended haplotype markersMwema, Hadija Saidi January 2011 (has links)
The aim of the present study was to evaluate the power of discrimination and genetic (diversity) parameters in the Y chromosome extended haploytpe markers in populations of Tanzania for forensic and populations studies. Eleven Y chromosome extended haplotype markers were selected for this study, these includes Minimal haplotypes markers i.e. DYS19, DYS390, DYS391, DYS392, DYS393, DYS385a/b, DYS389I/II and two additional markers DYS438 and DYS439. Six populations of Tanzania were investigated under this study. These populations were selected based on the language family categories / Niger Congo (Kuria and Sukuma), Nilo Saharan (Luo and Maasai) and Afro Asiatic (Iraqw and Alagwa).
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Genetic diversity of the Organic Cation Transporter 1 gene within the Cape Coloured PopulationBrendon Pearce January 2012 (has links)
<p>The aim of this study was to investigate the genetic diversity of the SLC22A1 gene and to deduce its possible pharmacogenetic implications within the Cape Coloured population of South  / Africa / a uniquely admixed population of immigrant Europeans, Asians and the indigenous populations. Recent studies have reported an abundance of polymorphic variants within this solute  / carrier transporter gene encoding for the organic cation transporter 1, as well as evidence linking these variants to an effect on metformin uptake. This study included establishing baseline  / frequency distribution of previously reported alleles for 20 SNP variants within the SLC22A1 gene, as well as the development of SNaPshot® / and Multiplex AS-PCR genotyping assays, and  / also exploring the possibility of using High-resolution melt (HRM) analysis as a costeffective alternative for SNP genotyping. Ethics clearance was obtained from the Ethics Committee of the  / University of the Western Cape. Biological samples in the form of buccal (oral) swabs were collected from 132 unrelated voluntary donors from the Cape Coloured population residing in the  / Cape Metropolitan area. Two SNaPshot® / Multiplex Systems were specifically designed for the study,successfully optimized and used for genotyping. Hundred genetic profiles were then generated for a total of 20 SNP variants on SLC22A1 gene, using this primer extension-based genotyping method that enables multiplexing up 10 SNPs. Population genetics data obtained for  / the investigated SNPs were analysed using various statistical analysis software. Important population genetic parameters were calculated, and possible pharmacogenetics implications were then discussed. Among others, allelic and genotypic frequencies, as well as linkage disequilibrium were determined and compared with world populations. Minor deviation from Hardy- Weinberg equilibrium was observed in the Cape Coloured population. No significantLinkage Disequilibrium between the investigated SNPs was observed in this population. A Multiplex allele specific &ndash / PCR (MAS-PCR) genotyping  / system was successfully designed and optimized for the genotyping of 10 SNPs from the SLC22A1. This system, also developed specifically for this study, was made of 2 multiplexes each covering 5 SNPs. It is an inexpensive genotyping assay that allows for efficient discrimination of SNP polymorphisms in one reaction tube with standard PCR conditions. A pilot study was  / conducted to explore the possibility of using High-resolution melt (HRM) analysis as a cost-effective alternative for SNP genotyping. In addition to genotyping, HRM analysis can be used to scan  / large numbers of samples for novel genetic variations.  / </p>
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Forensic identification of six of Tanzanian populations using the extended haplotype markersSaidi, Mwema Hadija January 2011 (has links)
The aim of the present study was to evaluate the power of discrimination and genetic(diversity) parameters in the Y chromosome extended haploytpe markers in populations of Tanzania for forensic and populations studies. Eleven Y chromosome extended haplotype markers were selected for this study, these includes Minimal haplotypes markers i.e. DYS19, DYS390, DYS391, DYS392, DYS393, DYS385a/b, DYS389I/II and two additional markers DYS438 and DYS439. Six populations of Tanzania were investigated under this study. These populations were selected based on the language family categories; Niger Congo (Kuria and Sukuma), Nilo Saharan (Luo and Maasai) and Afro Asiatic (Iraqw and Alagwa).Buccal swabs were collected from unrelated males from Mwanza province (Sukuma),Mara (Kuria and Luo), Arusha (Maasai and Iraqw) and Dodoma province (Alagwa).Samples were typed using ABI 377 Genetic Analyser (Applied Biosystem) followed by analysis using softwares Gelprocessor, GeneScan 3.0.0 (Applied Biosystems) and Genotyper 3.7 (Applied Biosystems). The data obtained were analysed by GenePop 4.0,Arlequin 3.11 and Genetix v.4.05.2 software packages. Analyses such as AMOVA, Fst population pairwise comparison, Factorial component Analysis were used to obtain Allele frequency, haplotype frequency, gene diversities among various loci and levels of gene flow between populations.For the overall individuals, the highest Gene Diversity value was 0.8251 (DYS385) and the lowest was 0.2723 (DYS392). The overall Haplotype Diversity was 0.9984 and Discrimination capacity resulted 84.27%. A total of 225 distinct haplotypes were identified in 267 individuals, 28 were shared, the most frequent haplotype was present in 5 individuals. The levels of genetic diversity for the haplotypes per group as revealed
by haplotype diversities confirmed that the most diverse group being Sukuma, Kuria,Iraqw, Maasai, Luo and Alagwa being the least diverse. The Discrimination capacity of these set of markers showed the highest value in Sukuma population (100%) subsequently followed by Iraqw, Luo, Maasai, Kuria and Alagwa (78.38%) being the lowest. Analysis of Molecular Variance showed a significant differentiation among populations, 93.96% of variance was found within population and 6.04% among population. Population pairwise results between all population pairs (except Sukuma and kuria and Alagwa and Luo) showed significant results (P < 0.05).
Genetic heterogeneity that was found among Tanzanian populations could not be
attributed to language barriers but was largely being contributed by a limited level of gene flow between these populations due to different ethnical, social, cultural and
historical backgrounds between them. All Y chromosome extended haplotype loci used in this study (except DYS392 and DYS391 which showed the lowest level of
polymorphism) were found to be likely useful for forensic application in Tanzania.
Furthermore the extended haplotype markers used in this study may be useful in the establishment of the National DNA database following the enactment of the Human DNA Legislation in Tanzania (http://www.parliament.go.tz). / Magister Scientiae - MSc
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Genotyping and Mutation Detection In Situ : Development and application of single-molecule techniquesGrundberg, Ida January 2011 (has links)
The human body is composed of trillions of cells closely working together to maintain a functional organism. Every cell is unique in molecular composition and can acquire genetic variations that might cause it to turn pathological. It is essential to develop improved tools to better understand the development of normal and disease tissue, ideally enabling single-cell expression studies in preserved context of complex tissue with single-nucleotide resolution. This thesis presents the development and application of a new in situ method for localized detection and genotyping of individual transcripts directly in cells and tissues. The described technique utilizes padlock probes and target-primed rolling circle amplification and is highly suitable for sensitive in situ analysis. First, a new strategy for directed cleavage of single stranded DNA was investigated, e.g. nucleic acid targets with extended 3´ ends, for successful initiation of rolling circle amplification. The presented cleavage strategy is simple and applicable for subsequent enzymatic reactions, e.g. ligation and polymerization. Specific cleavage of long target overhangs was demonstrated in synthetic oligonucleotides and in genomic DNA and the detection efficiency was substantially increased. For multiplex detection and genotyping of individual transcripts in single cells, a new in situ method was developed. The technique showed a satisfactorily detection efficiency and was later applied as a general mutation analysis tool for detection of KRAS point mutations in complex tumor tissue sections, e.g. formalin-fixed, paraffin-embedded tumor tissues and cytologic tumor imprints. Mutation status was assessed in patient samples by in situ padlock probe detection and results were confirmed by DNA-sequencing. Finally, the method was adapted for simultaneous detection of individual mRNA molecules and endogenous protein modifications in single cells using padlock probes and in situ PLA. This assay will be useful for gene expression analysis and exploration of new drugs with vague effector sites. To our knowledge, no other technique exists today that offers in situ transcript detection with single-nucleotide resolution in heterogeneous tissues. The method will especially be suitable for discrimination of highly similar transcripts, e.g. splice variants, SNPs and point mutations, within gene expression studies and for cancer diagnostics.
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High Resolution Genotyping of Chlamydia trachomatisChristerson, Linus January 2011 (has links)
Chlamydia trachomatis is an obligate intracellular bacterium of major human health concern, causing urogential chlamydia infections, lymphogranuloma venereum (LGV) and trachoma. Chlamydia is one of the most common sexually transmitted infections worldwide and can cause infertility. In the first four papers described herein we used a high resolution multilocus sequence typing (MLST) system to investigate the epidemiology of C. trachomatis, and showed that MLST is superior to conventional ompA genotyping with respect to resolution. In the fifth paper we simplified the methodology by developing and validating a multilocus typing (MLT) DNA microarray based on the MLST system. In more detail, MLST analysis of consecutive specimens from 2006 in Örebro County in Sweden, and comparison to specimens from 1999-2000, showed that the new variant C. trachomatis (nvCT) is monoclonal and likely has appeared in recent years. MLST analysis of LGV specimens from men who have sex with men (MSM) showed that the increase of LGV in Europe in the last decade indeed was a clonal outbreak, contrary to the USA where LGV might have been present all along. In the third paper, clinical symptoms could not be correlated with the MLST genotypes, suggesting, together with the combined results of all previous studies, that bacterial factors, if important, need to be understood in the context of host factors. MLST analysis of specimens from a high incidence C. trachomatis area in North Norway revealed interesting epidemiological details concerning unusual genetic variants, the nvCT and MSM, but found no significant difference in genetic diversity compared to two other geographic areas in Norway. Lastly, we developed a MLT array that provides high resolution while being rapid and cost-effective, which makes it an interesting alternative for C. trachomatis genotyping. In conclusion, the MLST system and the MLT array have proven to be useful tools and should now be applied in further investigations to improve our understanding of C. trachomatis epidemiology.
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Feline immunodeficiency virus: molecular subtyping and evaluation of potential prognostic indicatorsRebecca Kann Unknown Date (has links)
Abstract Feline immunodeficiency virus (FIV) is an important infectious agent of domestic cats worldwide. It has been classified into the Lentivirus genus of the Retroviridae family, together with human immunodeficiency virus (HIV). Five FIV subtypes (A, B, C, D and E) have been described based on sequence variation of the V3-V5 region of the envelope (env) gene. There is considerable sequence diversity within and between subtypes, which has been a major obstacle in the development of a successful vaccine. However, an FIV vaccine that incorporates inactivated whole viruses from subtypes A and D is now commercially available. Although the vaccine has been shown to be efficacious in protecting against challenge with homologous and a heterologous (subtype B) subtypes, its effectiveness against other viral variants is unknown. Therefore, identifying the type and diversity of FIV strains in different regions is important to establish the potential efficacy of the vaccine in areas where vaccination is to be implemented. The proviral DNA sequence of the V3-V5 region of the env gene was determined for 102 FIV-infected cats from locations in Australia, New Zealand and South Africa. Subtype A was the predominant subtype in Australia and South Africa, although subtype B and C were also identified in each of these countries, respectively. Both subtypes A and C were also present in New Zealand. Of interest, there were some samples in New Zealand and South Africa that demonstrated subtype assignment discrepancies when different regions of the genome were analysed, suggesting co-infection and/or recombination. Cats infected with FIV exhibit varying degrees of immunological impairment. Currently, prognosis for an FIV-infected cat is based on clinical signs alone, which is a relatively subjective measure. In HIV-infected patients it is recognised that viral RNA load correlates with disease stage and prognosis. This PhD research tested whether viral RNA load may be a useful prognostic marker in FIV infection. A real-time PCR assay was developed to quantify plasma viral RNA load in 42 FIV-infected cats at three different clinical stages (1:healthy, 2:unwell without signs of immunodeficiency, 3:unwell with signs of immunodeficiency). In cats older than 5 years of age, log-transformed viral RNA loads were significantly higher in cats in category 3 compared to cats in category 1. There were no significant differences in the viral RNA load of older cats in category 2 compared to category 1. There were no cats younger than 5 years of age in category 3 and there was no significant difference in viral RNA load between young cats in categories 1 and 2. Of the 15 cats for which follow-up data was available, eight showed no change in clinical signs, and seven showed a worsening of clinical signs with six of these showing a progression of clinical category including death. One of the cats in category 2 that progressed clinically had one of the highest viral RNA loads of cats in that category. Three of four cats from category 3 that were followed had either died or been euthanised. Two of these cats had among the highest viral RNA loads in the whole study, while the remaining cat (for which the definitive cause of death was not confirmed) had a relatively low viral RNA load. In summary, measurement of viral RNA load was found to be a potentially useful clinical and prognostic marker but further work is required to better assess its usefulness to veterinarians. Serum acute phase proteins were investigated as possible candidate markers of FIV disease with the aim of developing a more simplified assay that could be used as a prognostic marker for FIV infection. Blood samples from 43 FIV-infected and 25 FIV-negative cats were assayed for the concentration of four acute phase proteins. Both healthy and sick cats were included in the study. Compared to healthy cats, sick cats had significantly higher concentrations of serum amyloid A (P<0.05). Alpha 1-acid glycoprotein and haptoglobin were also found to be in higher concentrations in sick cats (P<0.1). Other variables such as age and gender were also associated with acute phase protein concentrations. With respect to FIV infection, it was found that in sick cats, serum amyloid A, in combination with the age of the cat, was the best predictor of FIV viral RNA load. Alpha 1-acid glycoprotein and haptoglobin were not significantly associated with FIV viral RNA load. Although health status did not influence albumin levels, they were found to be significantly lower in FIV-positive cats in comparison to FIV-negative cats (P<0.05). The frequent monitoring of viral RNA loads and CD4+ lymphocyte counts that is performed on HIV-infected patients is cost prohibitive in veterinary patients. This study showed that there is potential for the use of acute phase protein concentrations (in particular serum amyloid A) as alternative prognostic tools in FIV-infected cats. Further work, particularly longitudinal studies, is required to more definitively define changes in viral RNA load and acute phase protein concentrations throughout the course of FIV infection.
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