Anti-histone antibodies in dogs with leishmaniasis and glomerulonephritis

The association between serum anti-histone antibodies and glomerulonephritis was studied in 43 dogs with leishmaniasis (Leishmania infantum). Dogs with increased serum creatinine levels and urine protein-creatinine ratio >1 were considered to have glomerulonephritis. Moderately elevated anti-histone antibodies were found in 38.89% (7/18) of infected dogs without glomerulonephritis, whereas 88% of dogs with glomerulonephritis (22/25) showed moderate or strongly elevated anti-histone antibodies. Prevalence of positive anti-histone antibodies reactions and mean serum concentration was significantly higher (P < 0.001; P < 0.0001) in infected dogs with glomerulonephritis. Correlation between anti-histone antibodies and urine protein-creatinine ratio was significant when groups were analysed together (P < 0.046). Positive predictive value for glomerulonephritis of positive anti-histone antibodies was 88%. In conclusion, high anti-histone antibodies are significantly associated with glomerulonephritis. Although other factors must be involved, dogs with moderate or strong positive anti-histone antibodies reactions may have a higher probability to develop glomerular lesions in canine leishmaniasis.     

Local and systemic immune response in pigs during subclinical and clinical swine influenza infection

Local and systemic immune responses in pigs intranasally (IN) and intratracheally (IT) inoculated with swine influenza virus (SIV) were studied. No clinical signs were observed in IN-inoculated pigs, while IT-inoculated pigs developed typical signs of influenza. Significantly higher titres of specific antibodies and changes of haematological parameters were found only in IT-inoculated pigs. Because positive correlations between viral titre, local cytokine concentration, and lung pathology have been observed, we hypothesise that both viral load and the local secretion of cytokines play a role in the induction of lung lesions. It could be that a higher replication of SIV stimulates immune cells to secrete higher amounts of cytokines. The results of the present study indicate that pathogenesis of SIV is dependent on both, the damage caused to the lung parenchyma directly by virus, and the effects on the cells of the host's immune system.     

A survey on canine leishmaniasis and phlebotomine sand flies in central Italy

Zoonotic visceral leishmaniasis (ZVL) is a vector-transmitted zoonosis caused by the parasitic protozoan Leishmania infantum. Bloodsucking sand flies of the subfamily Phlebotominae are the obligatory insect hosts, and the dog is the only domestic reservoir.This study reports data from a survey of canine infection and sand fly phlebotomine monitoring in the province of Perugia in central Italy. The overall seroprevalence in a total of 100 dogs tested was 8% (95% confidence interval: 3.8-15.6%). Data analysis revealed that serological positivity was statistically associated with age (p-value = 0.03) and the area where dogs lived. Standard blacklight traps employed for sampling Culicoides midges in bluetongue disease surveillance were used in phlebotomine monitoring. A total of 5698 sand flies were collected and the two species, Leishmania competent vectors, were identified, Phlebotomus perfiliewi (50%) and Phlebotomus perniciosus (30%).     

Crossbreeding parameters of general immune response traits in White Leghorn chickens

Crossbreeding parameters of immune response traits were estimated from a set of well characterized crossbred populations derived from three chicken lines selected over 12 generations for three different general immune response traits and their F1, F2 and backcrosses. The three traits investigated were the selection criteria from each of the lines, i.e. antibody response to the Newcastle disease virus vaccine 3 weeks after vaccination (ND3), cell-mediated immune response (response to phytohemagglutinin, PHA) and phagocytic activity measured as carbon clearance (CC). Crossbreeding parameters included direct and maternal additive line effects, direct and maternal heterosis as well as direct epistatic recombination loss. They were estimated as linear combinations of genetic group effects estimated using animal model methodology. Significant line differences were obtained for ND3 and, to a lesser extent, CC. They were mainly due to direct effects, maternal effects being significant for none of the 3 traits. Significantly negative direct heterosis effects were also observed for ND3 and CC, but not for PHA. Maternal heterosis effects were not estimated for CC. They were non significant for PHA, and negative and significant (− 0.78 ± 0.24) for ND3. The significant favourable recombination gain estimated for ND3 (3.21 ± 0.88) indicates that epistatic interactions could be important for this trait.The present work shows that it was worthwhile to complete second generation crosses to be able to assess to what extent immunity gained by selection is maintained in advanced crossbred generations, and to compare the transmission of immune traits implicated in different aspects of immunity.     

Defining the immune response to Ehrlichia species using murine models

Pathogenic bacteria belonging to the family Anaplasmataceae include species of the genera Ehrlichia and Anaplasma. Ehrlichia chaffeensis, first known as the causative agent of human monocytic ehrlichiosis, also infects several vertebrate hosts including white-tailed deer, dogs, coyotes and goats. E. chaffeensis is transmitted from the bite of an infected hard tick, such as Amblyomma americanum. E. chaffeensis and other tick-transmitted pathogens have adapted to both the tick and vertebrate host cell environments. Although E. chaffeensis persists in both vertebrate and tick hosts for long periods of time, little is known about that process. Immunological studies will be valuable in assessing how the pathogen persists in nature in both vertebrate and invertebrate hosts. Understanding the host immune response to the pathogen originating from dual host backgrounds is also important to develop effective methods of diagnosis, control and treatment. In this paper, we provide our perspective of the current understanding of the immune response against E. chaffeensis in relation to other related Anaplasmataceae pathogens.     

Characterization of immune response in Staphylococcus aureus chronically infected bovine mammary glands during active involution

The aim of this study was to characterize the immune response in Staphylococcus aureus chronically infected bovine mammary glands during active involution. Twenty-one Holstein non-pregnant cows in late lactation either uninfected or with chronic naturally acquired S. aureus intramammary infections (IMI) were included in this study. Cows were slaughtered at 7, 14 and 21 d after cessation of milking and samples for immunohistochemical analysis were taken. Protein expression of toll-like receptor 2 (TLR2) and TLR4 was significantly higher in S. aureus-infected quarters than in uninfected controls at the three involution stages studied. Protein expression of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1α and IL-17 was significantly affected by IMI; being higher in S. aureus-infected than uninfected quarters during all evaluated stages. In S. aureus-infected and uninfected quarters protein expression of lactoferrin increased from day 7–14 of involution, decreasing significantly to day 21 in mammary quarters with chronic infections. The number of monocytes-macrophages was significantly higher in S. aureus-infected than in uninfected control quarters at 7 and 21 d of involution. The number of T lymphocytes was significantly higher in S. aureus-infected than in uninfected quarters at 7 and 14 d of involution while the number of B lymphocytes was significantly higher in S. aureus-infected than in uninfected quarters during all evaluated stages, showing a progressive increase as involution advanced. These results demonstrated a sustained and exacerbated innate and adaptive immune response during chronic S. aureus IMI, playing a critical role in the infection control during active involution.     

Cutaneous immune mechanisms in canine leishmaniosis due to Leishmania infantum

Canine leishmaniosis (CanL) caused by the parasite Leishmania infantum is a systemic disease with variable clinical signs. The disease is endemic in the Mediterranean countries and dogs are the main domestic reservoir of the parasite. The quite complicated immune response against the parasite is crucial for the evolution of CanL infection with the skin playing a major role in its immunopathogenesis.After the inoculation of Leishmania promastigotes into the dermis by sand fly bites, complement factors, Langerhan's cells, neutrophils, fibroblasts and keratinocytes are involved in the activation of the innate arm of the skin immune system, with the macrophages and dendritic cells to play a major key role.The effective activation of cellular immunity is the cornerstone of dog's resistance against the parasite. Promastigotes reaching the dermis are engulfed, processed and transferred by APCs to draining lymph nodes to stimulate naïve T-cells for proliferation and differentiation into armed effector T-cells. Th1 cells activate the infected macrophages to kill Leishmania, whereas Th2 cells divert the immune response to humoral immunity and down regulation of cellular immunity with Th1 cell anergy. Inhibition of co-stimulatory molecules expression by infected macrophages contributes to T-cell anergy. In canine subclinical infections cutaneous lymphocytic infiltrate and parasites are absent, as opposed to dogs with clinical leishmaniosis. CD8+ cells constitute a significant population of cellular immunity in CanL since they outnumber CD4+ cells in the dermis, producing IFN-γ in sub clinically infected dogs and high levels of IL-4 in dogs with clinical leishmaniosis.Numerous B-lymphocytes have been shown to heavily infiltrate the dermis at least in exfoliative dermatitis in CanL. A mixed Th1/Th2 cytokine profile has been found in the dermis of naturally infected with L. infantum dogs. In the skin of dogs with clinical leishmaniosis, where plasma cells outnumber T lymphocytes in the dermal infiltrate, there is an overproduction of IL-4, IL-13 and TNF-α leading to Th2-biased humoral immune response. The issue of humoral immunity polarization in CanL remains controversial. Much still needs to be learned about other mechanisms underlying the complex interaction between the skin immune system and the parasite.     

The immune response and PBMC subsets in canine visceral leishmaniasis before, and after, chemotherapy

Peripheral blood mononuclear cell subsets, in vitro lymphoproliferative response to leishmanial antigen, and Leishmania-specific serum antibody levels were examined in 11 dogs, naturally infected with L. infantum, and 9 healthy control dogs. A decrease in the percentage of CD4+ T-cells and an increase in the proportion of gammadelta T-cells and sIgG+ B-cells were observed during canine visceral leishmaniasis (CVL). These changes may be responsible for the marked humoral response and the absence of in vitro lymphoproliferation to mitogen and specific parasite antigens. This possibility was supported by the analysis of these subsets after treatment with amphotericin B. One month after therapy, a significant increase in the percentage of CD4+ T-cells and a decrease of gammadelta T-cells and sIgG+ B-cells were observed. At the same time, the lymphocyte blastogenesis assay with leishmanial antigen was positive and the levels of specific antibodies to Leishmania were significantly lower than before the treatment. Five months after therapy, lymphocyte proliferative response to LSA disappeared, antibody and lymphocyte subsets levels returned to those observed during CVL. Therapeutic failure in CVL is associated with the inability of antileishmanial drugs to completely revert the profound immunodepression induced by the infection and prevent relapse.     

Assessment of serological tests for the diagnosis of canine visceral leishmaniasis

An immunoenzymatic assay (ELISA), an indirect immunofluorescence antibody test (IFAT) with different antigens (ELISA-Leishmania chagasi, ELISA-L. major-like, IFAT-L. chagasi and IFAT-L. major-like), and an immunochromatographic test were assessed for the diagnosis of canine visceral leishmaniasis (CVL). Serum samples from 144 dogs from an endemic area for visceral leishmaniasis in the municipality of Rio de Janeiro were tested. The sensitivities of the serological tests were 93%, 100%, 73%, 60% and 93%, with specificities of 87%, 92%, 77%, 96% and 92% for the ELISA-L. major-like, ELISA-L. chagasi, IFAT-L. major-like, IFAT-L. chagasi and the immuno chromatographic test, respectively. ELISA-L. chagasi was the best test for the diagnosis of CVL, but the immunochromatographic test could be a useful alternative as it offers simple and rapid diagnosis without the need for a specialized laboratory.     

Plasma interleukin-6 response is predictive for severity and mortality in canine systemic inflammatory response syndrome and sepsis

BACKGROUND: Sepsis is still a major cause of death in both human and veterinary medicine. Early diagnosis is essential for appropriate treatment. Identification of patients at risk for developing sepsis is already possible in human medicine through the measurement of plasma interleukin-6 (IL-6) levels. In veterinary medicine, however, this has been investigated only in canine experimental models. OBJECTIVES: The purpose of this study was to measure IL-6 plasma levels in dogs with naturally occurring systemic inflammatory response syndrome (SIRS) and sepsis and to analyze the value of IL-6 as a predictive parameter for severity and mortality. METHODS: Included in the study were 79 dogs that had been admitted to the small animal clinics of Munich and Berlin from July 2004 to July 2005 and that satisfied the diagnostic criteria for SIRS and sepsis as defined using established parameters. Measurement of plasma IL-6 levels on days 0, 1, and 2 was performed by the use of a colorimetric bioassay based on IL-6-dependent cell growth. RESULTS: Septic foci were identified in 43 patients (septic group), and 36 patients were enrolled in the SIRS group. The frequency of positive blood cultures was 11%. The overall mortality rate was 48%. Higher plasma IL-6 levels on the day of admission were significantly correlated with a more severe degree of disease, increased mortality rate, and earlier fatality. CONCLUSIONS: Plasma IL-6 concentration is predictive of outcome in canine SIRS and sepsis and may be a valuable laboratory parameter for assessing critically ill dogs.     

Application of a recombinant protein for the serological diagnosis of canine leishmaniasis

This work reports the results obtained by a new enzyme-linked immunosorbent assay (ELISA) test developed for the serological diagnosis of canine leishmaniasis.The new ELISA is based on a recombinant protein obtained by joining different antigens of Leishmania infantum.Test performances have been evaluated through the screening 227 sera of dogs, infected and uninfected by L. infantum. The new ELISA test has been compared to the indirect immunofluorescent-antibody test (IFAT) as a reference assay of canine leishmaniasis, and to a commercial ELISA.Excluding from the total number of IFAT positive sera the 27 sera with IFAT titre 1:40 (considered doubtful), the recombinant ELISA showed 97.0% specificity, 93.9% sensitivity and 95.5% agreement with IFAT. The commercial ELISA showed 78.2% specificity, 94.9% sensitivity and 86.5% agreement with IFAT.The results demonstrate a higher performance of the new recombinant ELISA test for the detection of negative samples, with a greater agreement with the reference test (IFAT).     

The use of 17-hydroxyprogesterone in the diagnosis of canine hyperadrenocorticism

A number of dogs are seen with clinical signs consistent with hyperadrenocorticism (HAC), supporting CBC and biochemical findings, but the disease cannot be confirmed with either the ACTH stimulation test or the low-dose dexamethasone suppression test (LDDST). Therefore, another screening test is required to aid diagnosis in these atypical cases of HAC. The aim of this study was to investigate whether measuring 17-hydroxyprogesterone (OHP) concentrations could be used in this role. Plasma cortisol and OHP concentrations were measured in dogs with clinical signs suggestive of HAC before and after administration of exogenous ACTH. In dogs with HAC, plasma OHP showed an exaggerated response to ACTH stimulation. This was seen in both typical cases of HAC with a positive cortisol response to ACTH administration and in atypical cases with negative screening test results. The test can be performed on plasma already taken for a conventional ACTH stimulation test. Post-ACTH OHP concentrations decreased after treatment with mitotane or adrenalectomy. These results suggest that OHP measurements can be used as an aid to diagnose and manage canine HAC.     

Click and low-, middle-, and high-frequency toneburst stimulation of the canine cochlea

A method was developed to deliver tonebursts ranging in frequency from 1 to 32 kHz for frequency-specific assessment of the canine cochlea. Brainstem auditory-evoked responses (early latency responses, 0-10 ms) to a click (CS) and to 1-, 2-, 4-, 8-, 12-, 16-, 24-, and 32-kHz toneburst stimulations (TS) were compared at 80-dB sound pressure level stimulus (SPL) intensity in 10 adult dogs. All stimulations yielded a 5-7 positive wave pattern, with the exception of the 1-kHz TS, which evoked a frequency-following response (FFR). Thresholds were lowest for the CS and the 12- and 16-kHz TS. All individual peak latencies for TS were significantly (P < or = .05) longer than for CS. Peak I latencies were significantly (P < or = .05) shorter for the 12- and 16-kHz TS than for the other TS. Interpeak latencies I-V were significantly (P < or = .05) longer for the 4- to 32-kHz TS than for CS. Differences in interpeak latencies I-III were not significant. Amplitudes of waves I and V were significantly (P < or = .05) lower for TS than for CS, except for higher wave V amplitude (P < or = .05) at 2- and 32-kHz TS. Peak I-V amplitude ratios were significantly (P < or = .05) higher for the 2-, 4-, 16-, 24-, and 32-kHz TS and lower for the 8- and 12-kHz TS, compared to CS. We conclude that reproducible information on frequency specificity of the canine cochlea can be obtained by TS. This report provides a normative database for parameters needed to evaluate frequency-specific hearing loss in dogs.     

Effect of difference doses of Newcastle disease vaccine immunization on growth performance,plasma variables and immune response of broilers

Background

As a member of the Paramyxoviridae group, Newcastle disease virus (NDV) is the key causative agent of Newcastle disease (ND) that attacks chickens, turkeys and other avian birds. Surviving birds showed lower feed utilization, growth performance or egg production, which results in severe economic losses. The purpose of this study was to determine the effect of different doses of NDV immunization on growth performance, plasma variables and immune response of broiler chickens.

Methods

A total of 480 one-day-old Arbor Acres broilers were randomly administrated with 0, 4, 6 or 8 doses of NDV at 12 d and 28 d, respectively. Each group consisted of ten replicates with 12 birds each. Growth performance and organ weight were recorded. Plasma concentration of glucose, total protein, cholesterol, triglycerides and nonesterified fatty acid was determined using commercial kits. The concentration of plasma corticosterone and insulin was measured using commercially available radio immune assay kits. Serum antibody titer and peripheral blood lymphocyte proliferation were also recorded.

Results

The results showed that NDV decreased body weight gain (BWG), and increased Feed:Gain ratio at 1–21 d at all doses (P < 0.05). Plasma insulin concentration was lower in all immunization groups after the first immunization at 12 d (P < 0.01). The rest of the plasma indexes were not affected by NDV immunization, including glucose, total protein, cholesterol, triglycerides, nonesterified fatty acid, heterophil/lymphocyte ratio, as well as the proliferation of peripheral blood lymphocyte (P > 0.05). Compared with the control group, NDV treatment elevated NDV antibody titer at 10 d after the first inoculation (P < 0.05), and at d 5, 9 and 13 after the second inoculation (P < 0.05). Repeated NDV inoculation had no deleterious impacts on body composition at 42 d, and nutrient accretion rates at 8–42 d (P > 0.05).

Conclusions

In conclusion, NDV challenge decreased BWG and feed efficiency in earlier stage of growth. However, NDV treatment at 6 doses down-regulated the Feed:Gain ratio by 6.36 % throughout the whole growing period. These data suggest that appropriate lower doses of NDV inoculation increase feed efficiency of broiler chickens.

Electronic supplementary material

The online version of this article (doi:10.1186/s40104-015-0019-y) contains supplementary material, which is available to authorized users.     

Novel markers of inflammatory response and hepatic dysfunction in canine leishmaniasis

Dogs are the main host of Leishmania infantum, and the clinical presentation may range from asymptomatic to systemic manifestations. The immune mechanisms in infected, but clinically healthy dogs, prevails Th1 response mediated by cytokines. In this sense, adenosine deaminase (ADA) and butyrylcholinesterase (BChE) are considered as key enzymes in several physiological processes, including the modulation of inflammatory process. Considering the variable immune response against Leishmania and the known participation of ADA and BChE, the aim of this study was to assess the relation between these two enzymes with the inflammatory response as well as hepatic function in dogs naturally infected with L. infantum. For this purpose, the activity of ADA and BChE was assessed in sera of 24 dogs naturally infected with L. infantum, plus 17 healthy dogs. The naturally infected dogs had clinical signs compatible with leishmaniasis and sera activities of ADA (P < 0.01) and BChE (P < 0.05) decreased, when compared to the healthy group. The reduction of ADA activity probably represented an effect on inflammatory response, especially due to the decreased hydrolysis of extracellular adenosine, might in order to protect against tissue damage and, also, setting a down-regulation on pro-inflammatory cytokines. BChE enzyme had no effect on modulating the immune response in leishmaniasis, but it decreased, a fact may related to deficiency of synthesis in the liver. Therefore, ADA and BChE activities reduced probably in order to protect against extra tissue damage and due failure in synthesis, respectively.     

新城疫病毒感染绵羊诱导免疫应答反应的实验研究

为探索新城疫病毒(NDV)作为羊病毒病疫苗载体的可行性,验证NDV感染绵羊的可能性,本研究采用NDV Clone-30株分别通过滴鼻和气管灌注两种途径接种绵羊,接种后观察临床症状,检测接种动物排毒情况,通过血凝抑制试验检测接种绵羊特异性血凝抑制抗体,ELISA试验检测接种绵羊血清特异性IgG抗体,微量中和试验检测接种绵羊血清中和抗体.研究结果表明,NDV在绵羊体内是非致病性的,并且通过两种接种途径在绵羊体内均可以产生血凝抑制抗体、NDV特异性IgG抗体和中和抗体反应.本研究结果表明NDV有可能作为宿主限制性疫苗载体用于预防无特效疫苗的羊类疾病,且与气管灌注接种途径比,滴鼻接种途径相对安全.     

Factors affecting the occurrence, duration of hospitalization and final outcome in canine parvovirus infection

The objectives of this matched case-control study in a veterinary teaching hospital were to investigate the influence of signalment and historical data on the odds of occurrence of canine parvovirus (CPV) enteritis and the potential usefulness of the clinical signs and clinicopathologic abnormalities recorded on admission as prognostic indicators of mean duration of hospitalization (DOH) and outcome of the disease. Ninety-four puppies with natural CPV enteritis and 188 age-matched controls were studied. The odds to develop CPV enteritis were higher in purebreds compared to mixed-breed puppies. Vomiting and depression at the time of admission were associated with a prolongation of DOH by 2 and 1.75 days, respectively. The lymphopenic and hypoalbuminemic dogs were hospitalized for 1.9 and 2.5 more days, respectively, compared to those without these abnormalities. The odds of non-survival were higher in those puppies with evidence of systemic inflammatory response syndrome (SIRS) at the time of admission.