Utility of thoracic ultrasonography in a rapid diagnosis of angiostrongylosis in young dogs presenting with respiratory distress.

The nematode, Angiostrongylus vasorum is a nematode that lives in the pulmonary arteries of canids and has an obligate gastropod intermediate host. It can cause various clinical signs. with the two most common clinical scenarios consisting of acute respiratory distress and haemorrhagic diathesis, either separately or together. Younger dogs (< 2 years) are overrepresented, and dogs often show pulmonary granulomata (radiographically and pathologically). Thoracic ultrasonography offers a safe, rapid, commonly available, non-invasive means of assessing the lungs. We prospectively examined the utility of thoracic ultrasonography in the diagnosis of angiostrongylosis in 26 client-owned dogs <2 years old, presenting with respiratory distress. We identified small hypoechoic subpleural nodules in 15/26 dogs; 14 of these were subsequently confirmed to have angiostrongylosis by faecal Baermann concentration test, A. vasorum antigen testing or both. The remaining 11 dogs without subpleural nodules had negative faecal analysis and A. vasorum antigen testing and diagnosed with other respiratory diseases. This resulted in a sensitivity of 100% and a specificity of 92% for the detection of angiostrongylosis by thoracic ultrasonography in young dogs presenting with respiratory distress. Our results suggest that thoracic ultrasonography might offer a safe, rapid, relatively accurate diagnostic test for diagnosis of angiostrongylosis in young adult dogs with respiratory distress living in endemic areas.

Resistance of mice to Leptospira infection and correlation with chemokine response.

Leptospirosis is globally widespread neglected disease, affecting most mammalian species. Clinical signs can be confused with other diseases which make the diagnosis and treatment difficult. Chemokines and cytokines are known for their role in the inflammatory and immune response to infections. The profile determination of chemokines' expressions in the course of infection may elucidate the defense mechanisms of the host and support the search for effective treatment strategies. We investigated the mechanisms of innate immunity through the comparison of chemokines induced during infection with L. interrogans in mice with different levels of susceptibility. We used lung and spleen tissues samples of mice from C3H/HeJ, C3H/HePas and Balb/c, respectively sensitive, intermediate susceptibility and resistant to the pathogen. The inoculation of L. interrogans in C3H/HeJ mice led a comparatively smaller change in chemokines expression in both spleen and lung tissues. In samples from spleens and lungs of C3H/HePas and Balb/c the higher increases occurred on CXCL9, CXCL16, CXCL5, CCL8 and CCL5 in Balb/c. Given the same genetic background, the differences in the responses of C3H/HePas compared to C3H/HeJ mice strongly suggest the role of chemokines for the survival of parental strain. Therefore, the greatest increase in CXC chemokines appears to be efficient to induce migration of cells to the secondary lymphoid organs and affected tissues, which is important to control infection. Overall, CXC chemokines are important for the activation and attraction of T cell and may influence the course and control of the infection in resistant Balb/c mice.

Genetic linkage analysis identifies Pas1 as the common locus modulating lung tumorigenesis and acute inflammatory response in mice.

Selective breeding for the acute inflammatory response (AIR) generated two mouse lines characterized by maximum (AIRmax) and minimum (AIRmin) responses, explained by the additive effect of alleles differentially fixed in quantitative trait loci (QTLs). These mice also differ in their susceptibility to lung tumorigenesis, raising the possibility that the same loci are involved in the control of both phenotypes. To map the QTLs responsible for the different phenotypes, we carried out a genome-wide linkage analysis using single-nucleotide polymorphism arrays in a pedigree consisting of 802 mice, including 693 (AIRmax × AIRmin)F2 intercross mice treated with urethane and phenotyped for AIR and lung tumor multiplicity. We mapped five loci on chromosomes 4, 6, 7, 11 and 13 linked to AIR (logarithm of odds (LOD)=3.56, 3.52, 15.74, 7.74 and 3.34, respectively) and two loci linked to lung tumor multiplicity, on chromosomes 6 and 18 (LOD=12.18 and 4.69, respectively). The known pulmonary adenoma susceptibility 1 (Pas1) locus on chromosome 6 was the only locus linked to both phenotypes, suggesting that alleles of this locus were differentially fixed during breeding and selection of AIR mice. These results represent a step toward understanding the link between inflammation and cancer.

Neutralizing activity and secretory IgA antibodies reactive with rotavirus SA-11 (serotype G3) in colostrum and milk from Brazilian women.

BACKGROUND: Rotavirus is an important aetiological agent for severe diarrhoea in infants and young children worldwide. Anti-rotavirus antibodies in human colostrum and milk may interfere with rotavirus vaccination seroconversion. AIMS: To verify the presence of anti-rotavirus secretory IgA antibodies (SIgA) and the neutralizing capacity of 30 colostrum and 30 milk samples from Brazilian women in two different centres and analyze their persistence throughout lactation. METHODS: Colostrum and milk samples from healthy nursing mothers were tested for the presence of anti-rotavirus SIgA using conventional ELISA and their capacity to neutralize rotavirus using MA-104 cell cultures. Total IgA concentrations and anti-rotavirus SIgA levels were measured in samples collected from three mothers during 90 or 240 days of the lactation period. RESULTS: Colostrum samples showed higher levels of anti-rotavirus SIgA and higher neutralizing ability than in milk. However, these antibodies levels were not statistically different. In addition, there was no correlation between antibody levels and the neutralizing activity observed in colostrum and milk samples. Follow-up of three mothers demonstrated the persistence of anti-rotavirus and total IgA levels throughout lactation. CONCLUSIONS: These results support the encouragement of breastfeeding as a mechanism of protection against rotavirus infection in lactating infants. Components other than SIgA antibodies might play an important role in virus neutralization.

Association study by genetic clustering detects multiple inflammatory response loci in non-inbred mice

We tested the possibility to map loci affecting the acute inflammatory response (AIR) in an (AIRmax AIRmin) F2 intercrossmouse population derived from non-inbred parents, by association analysis in the absence of pedigree information. Using 1064 autosomal single nucleotide polymorphisms (SNPs), we clustered the intercross population into 12 groups of genetically related individuals. Association analysis adjusted for genetic clusters allowed to identify two loci, inflammatory response modulator 1 (Irm1) on chromosome 7 previously detected by genetic linkage analysis in the F2 mice, and a new locus onchromosome 5 (Irm2), linked to the number of infiltrating cells in subcutaneous inflammatory exudates (Irm1: P»6.3 10 7; Irm2: P»8.2 10 5) and interleukin 1 beta (IL-1b) production (Irm1: P»1.9 10 16; Irm2: P»1.1 10 6). Use of a polygenic model based on additive effects of the rare alleles of 15 or 18 SNPs associated at suggestive genome-wide statistical threshold(Po3.4 10 3) with the number of infiltrating cells or IL-1b production, respectively, allowed prediction of the inflammatory response of progenitor AIR mice. Our findings suggest the usefulness of association analysis in combination with genetic clustering to map loci affecting complex phenotypes in non-inbred animal species.

Association study by genetic clustering detects multiple inflammatory response loci in non-inbred mice.

We tested the possibility to map loci affecting the acute inflammatory response (AIR) in an (AIRmax × AIRmin) F2 intercross mouse population derived from non-inbred parents, by association analysis in the absence of pedigree information. Using 1064 autosomal single nucleotide polymorphisms (SNPs), we clustered the intercross population into 12 groups of genetically related individuals. Association analysis adjusted for genetic clusters allowed to identify two loci, inflammatory response modulator 1 (Irm1) on chromosome 7 previously detected by genetic linkage analysis in the F2 mice, and a new locus on chromosome 5 (Irm2), linked to the number of infiltrating cells in subcutaneous inflammatory exudates (Irm1: P=6.3 × 10(-7); Irm2: P=8.2 × 10(-5)) and interleukin 1 beta (IL-1ß) production (Irm1: P=1.9 × 10(-16); Irm2: P=1.1 × 10(-6)). Use of a polygenic model based on additive effects of the rare alleles of 15 or 18 SNPs associated at suggestive genome-wide statistical threshold (P<3.4 × 10(-3)) with the number of infiltrating cells or IL-1ß production, respectively, allowed prediction of the inflammatory response of progenitor AIR mice. Our findings suggest the usefulness of association analysis in combination with genetic clustering to map loci affecting complex phenotypes in non-inbred animal species.

Periodontitis and arthritis interaction in mice involves a shared hyper-inflammatory genotype and functional immunological interferences.

Periodontitis (PD) and rheumatoid arthritis (RA) have been found to be clinically associated and to share the chronic nature of the inflammatory reaction associated with bone resorption activity. However, the mechanisms underlying such association are unknown. Therefore, we examined the basis of Actinobacillus actinomycetemcomitans- and Porphyromonas gingivalis-induced PD and pristane-induced arthritis (PIA) interaction in mice. Higher severity PD in the genetically inflammation prone acute inflammatory reactivity maximum (AIRmax) mice strain was associated with higher levels of TNF-alpha, IL-1beta, IL-17, matrix metalloproteinase (MMP)-13, and RANKL, whereas PD/PIA co-induction resulted in even higher levels of IL-1beta, IFN-gamma, IL-17, RANKL, and MMP-13 levels. Conversely, PD/PIA co-induction in AIRmin strain did not alter the course of both pathologies. PIA/PD co-induction resulted in altered expression of T-cell subsets transcription factors expression, with T-bet and RORgamma levels being upregulated, whereas GATA-3 levels were unaltered. Interestingly, PIA induction resulted in alveolar bone loss, such response being highly dependent on the presence of commensal oral bacteria. No differences were found in PIA severity parameters by PD co-induction. Our results show that the interaction between experimental PD and arthritis in mice involves a shared hyper-inflammatory genotype and functional interferences in innate and adaptive immune responses.

Sirolimus in combination with FTY720: analysis of urinary and serum parameters.

The goal in transplantation is to obtain immunosuppressant combinations that decrease the incidence of acute and chronic rejection but cause fewer side effects. FTY720 is a new immunomodulator that prevents experimental allograft rejection without inhibiting T-cell activation. It is currently under clinical investigation for multiple sclerosis. We investigated whether FTY720 in combination with sirolimus (SRL) could cause renal toxicity in C57BL/6 mice when administered for 21 days. Serum creatinine and 24-hour urinary creatinine concentrations were assessed by enzymatic colorimetric assays. Urinary protein concentration was measured by the Bradford protein assay. Whereas serum creatinine levels were increased in FTY720 + SRL-treated animals, there were no changes in urinary volume, urinary protein levels, serum urea concentration, creatinine clearance, and kidney structure. Our findings suggested that FTY720 monotherapy for multiple sclerosis and other diseases could play an important immunomodulatory role without causing the side effects frequently observed with other transplantation regimens.

Chemokines expression during Leptospira interrogans serovar Copenhageni infection in resistant BALB/c and susceptible C3H/HeJ mice

The role of innate immune responses in protection against leptospirosis remains unclear. We examined the expression of the chemokines CCL2/JE (MCP-1), CCL3/MIP-1á (MIP-1á) and CXCL1/KC (IL-8) regarding resistance and susceptibility to leptospirosis in experimental mice models BALB/c and C3H/HeJ, respectively. A virulent strain of Leptospira interrogans serovar Copenhageni was used in this study. Twenty-five animals of each mouse strain of C3H/HeJ and BALB/c, were infected intraperitoneally with 106 cells. Five un-infected animals of each strain were kept as control. Mortality of C3H/HeJ mouse was observed while BALB/c mice were asymptomatic. The presence of leptospire DNA in tissues of infected animals was demonstrated by PCR. Chemokines were measured in serum, spleen, liver, kidney and lung of both strains of animals using immunoenzymatic assay (ELISA). Elevations in the levels of chemokines MCP-1 and IL-8 occurred in all organs and sera of C3H/HeJ and BALB/c infected mice. The levels of MIP-1á were lower when compared to MCP-1 and IL-8 in all analyzed organs, with a slight increase in liver and kidney. Our results indicate that the expression of inflammatory mediators can vary greatly, depending on the tissue and mouse strains. It is possible that the resistance to Leptospira can be partially correlated to the increase of MIP-1á observed in BALB/c mice, while an increasing and a sustained expression of MCP-1 and IL-8 in the lungs of C3H/HeJ mice can be correlated to the severity and progression of leptospirosis.

A new model of outbred genetically selected mice which present a strong acute inflammatory response in the absence of complement component C5.

OBJECTIVE: Mice selected for a strong (AIRmax) or weak (AIRmin) acute inflammatory response present different susceptibilities to bacterial infections, autoimmune diseases and carcinogenesis. Variations in these phenotypes have been also detected in AIRmax and AIRmin mice rendered homozygous for Slc11a1 resistant (R) and susceptible (S) alleles. Our aim was to investigate if the phenotypic differences observed in these mice was related to the complement system. MATERIAL: AIRmax and AIRmin mice and AIRmax and AIRmin groups homozygous for the resistance (R) or susceptibility (S) alleles of the solute carrier family 11a1 member (Slc11a1) gene, formerly designated Nramp-1. METHODS AND RESULTS: While no difference in complement activity was detected in sera from AIRmax and AIRmin strains, all sera from AIRmax Slc11a1 resistant mice (AIRmax(RR)) presented no complement-dependent hemolytic activity. Furthermore, C5 was not found in their sera by immunodiffusion and, polymerase chain reaction and DNA sequencing of its gene demonstrated that AIRmax(RR) mice are homozygous for the C5 deficient (D) mutation previously described in A/J. Therefore, the C5D allele was fixed in homozygosis in AIRmax(RR) line. CONCLUSIONS: The AIRmax(RR) line is a new experimental mouse model in which a strong inflammatory response can be triggered in vivo in the absence of C5.