Association between haptoglobin and IgM levels and the clinical progression of caseous lymphadenitis in sheep

Mycobacterium bovis BCG expressing the proteins CP40 or CP09720 of Corynebacterium pseudotuberculosis promotes protection in mice after challenge

In this study, we assessed the survival and immune response of mice vaccinated with recombinant Mycobacterium bovis BCG Pasteur that expressed the CP40 or CP09720 proteins after the mice were challenged with a C. pseudotuberculosis MIC-6 virulent strain. Six groups of mice (n = 10 mice per group) were immunised with a sterile 0.9% saline solution (G1), 106 CFU of M. bovis BCG Pasteur (G2), 106 CFU of M. bovis BCG/cp40 (G3), 106 CFU of M. bovis BCG/cp09720 (G4), M. bovis BCG/cp40 boosted with rCP40 (G5), and M. bovis BCG/cp09720 boosted with rCP09720 (G6). The highest survival rate of 90% was observed in the G5 group, followed by 80% in the G6 group and 70% in the G3 and G4 groups. Moreover, a significantly greater induction of IFN-γ and IL-10 was found in the G3 group and higher IL-17 levels were recorded in the G5 group compared to their levels in the control group (G1) (p < 0.05). A specific humoral immune response (total IgG) was found in the G5 and G6 groups on day 42 compared to the level of response in the G1 group. These results indicated that the vector vaccine elicited significantly greater survival of mice in all experimental groups after a strong virulent challenge and induced a strong immune response.

Evaluation of Oxidative Status, Cytokines, Acute Phase Proteins and Cardiac Damage Markers in Sheep Naturally Infected with Babesia ovis

PURPOSE

Babesiosis is a tick-borne disease caused by protozoon species in the Babesia genus of the Babesiadae family. The systemic inflammatory response induced by infection is considered to be an important feature of the pathophysiology of ovine babesiosis. In this study, it was aimed to determine serum oxidative status, levels of some cytokines, acute phase proteins and heart damage markers in babesiosis infection.

MATERIALS AND METHODS

A sample of 40 sheep was used for this purpose, of which 20 were healthy and 20 were infected with Babesia ovis. Babesia infection was diagnosed from Giemsa-stained peripheral blood smears. Infection was also confirmed by the polymerase chain reaction (PCR). Sera from blood samples was tested for oxidative stress parameters (malondialdehyde [MDA], total antioxidant status [TAS], superoxide dismutase [SOD], catalase [CAT] and glutathione peroxidase [GPx]), cytokines (interleukins IL-6, IL-1β, IL-10, tumour necrosis factor α (TNF-α) and interferon-ϒ [IFN-ϒ]), acute-phase proteins (C-reactive protein [CRP], serum amyloid A [SAA] and haptoglobin [Hp]) and specific (troponin I [cTnI], creatine kinase-MB [CK-MB]) and nonspecific (lactate dehydrogenase [LDH], aspartate transaminase [AST]) cardiac damage markers.

RESULTS

MDA, SOD, CAT, Hp, TAS, IL-6, IL-10, TNF-α, IL-1β, INF-γ, AST, LDH, CK-MB mass and troponin I values were higher in the patient group than in the healthy group (P < 0.05). However, there was not found to be a statistical difference between the healthy and patient groups in terms of GPx, SAA and CRP values (P > 0.05).

CONCLUSIONS

It can be stated that serum levels of oxidative stress, some acute phase proteins and cardiac damage markers may increase in naturally infected sheep with babesiosis.

Comparative Characterization of Immune Response in Sheep with Caseous Lymphadenitis through Analysis of the Whole Blood Transcriptome

Caseous lymphadenitis (CL) is a chronic contagious disease that affects small ruminants and is characterized by the formation of pyogranulomas in lymph nodes and other organs. However, the pathogenesis of this disease and the response of the host genome to infection are not yet fully understood. This study aimed to investigate the whole blood transcriptome and evaluate differential gene expression during the later stages of CL in naturally infected ewes. The study included diseased, serologically positive (EP), exposed, serologically negative (EN) ewes from the same infected flock and healthy ewes (CN) from a different flock. RNA sequencing was performed using the Illumina NextSeq system, and differential gene expression was estimated using DESeq2 and Edge R approaches. The analysis identified 191 annotated differentially expressed genes (DEGs) in the EP group (102 upregulated and 89 downregulated) and 256 DEGs in the EN group (106 upregulated and 150 downregulated) compared to the CN group. Numerous immunoregulatory interactions between lymphoid and nonlymphoid cells were influenced in both EP and EN ewes. Immune DEGs were preferentially assigned to antigen presentation through the MHC complex, T lymphocyte-mediated immunity, and extracellular matrix interactions. Furthermore, the EP group showed altered regulation of cytokine and chemokine signaling and activation and recombination of B-cell receptors. Conversely, NF-kappa B signaling, apoptosis, and stress response were the main processes influenced in the EN group. In addition, statistically significant enrichment of the essential immune pathways of binding and uptake of ligands by scavenger receptors in EP and p53 signaling in the EN group was found. In conclusion, this study provides new insights into the disease course and host-pathogen interaction in naturally CL-infected sheep by investigating the blood transcriptome.

Immunoprophylactic properties of the Corynebacterium pseudotuberculosis-derived MBP:PLD:CP40 fusion protein

Caseous lymphadenitis (CLA) is a disease that affects small ruminants, and the best way to prevent its spread on a herd is through immunoprophylaxis. Thus, we aimed to evaluate the MBP:PLD:CP40 fusion protein as a new CLA immunogen. The fusion protein was constructed by combining Corynebacterium pseudotuberculosis PLD and CP40 proteins with maltose-binding protein (MBP) as an intrinsic adjuvant. The antigenicity, allergenic potential, prediction of B epitopes, binding to MHC receptors, and docking on the Toll-Like 2 receptor were evaluated in silico. MBP:PLD:CP40 was expressed and purified. 40 BALB/c were divided into four groups (G1 - control, G2 - Saponin, G3 - MBP:PLD:CP40, and G4 - rPLD + rCP40). Total IgG, IgG1, and IgG2a were quantified, and the expressions of cytokines after splenocyte in vitro stimulation were assessed. Mice were challenged 42 days after the first immunization. The in silico analysis showed that MBP:PLD:CP40 has immunogenic potential, does not have allergic properties, and can dock on the TRL2 receptor. MBP:PLD:CP40 stimulated the production of IgG1 antibodies in a fivefold proportion to IgG2a, and TNF and IL-17 were significantly expressed in response to the antigenic stimuli. When rPLD and rCP40 were used together for immunization, they could induce IFN-γ and IL-12, but with no detectable antibody production. The G3 and G4 groups presented a survival of 57.14% and 42.86%, respectively, while the G1 and G2 mice were all dead 15 days after the challenge. MBP:PLD:CP40 partially protected the mice against C. pseudotuberculosis infection and can be considered a potential new CLA immunogen. KEY POINTS: • The fusion protein induced more IgG1 than IgG2a antibodies; • The fusion protein also induced the expression of the TNF and IL-17 cytokines; • Mice inoculated with MBP:PLD:CP40 presented a 57.14% survival.

Chemokine production induced by Corynebacterium pseudotuberculosis in a murine model

Corynebacterium pseudotuberculosis is the etiological agent of caseous lymphadenitis. The main clinical sign of this disease is the development of granulomas, especially in small ruminants; however, the pathways that are involved in the formation and maintenance of these granulomas are unknown. Cytokines and chemokines are responsible for the migration of immune cells to specific sites and tissues; therefore, it is possible that chemokines participate in abscess formation. This study aimed to evaluate the induction of chemokine production by two C. pseudotuberculosis strains in a murine model. A highly pathogenic (VD57) and an attenuated (T1) strain of C. pseudotuberculosis, as well as somatic and secreted antigens derived from these strains, was used to stimulate murine splenocytes. Then, the concentrations of the chemokines CCL-2, CCL-3, CCL-4, and CCL-5 and the cytokines IL-1 and TNF were measured in the culture supernatants. The VD57 strain had a higher ability to stimulate the production of chemokines when compared to T1 strain, especially in the early stages of stimulation, which can have an impact on granuloma formation. The T1 lysate antigen was able to stimulate most of the chemokines studied herein when compared to the other antigenic fractions of both strains. These results indicate that C. pseudotuberculosis is a chemokine production inducer, and the bacterial strains differ in their induction pattern, a situation that can be related to the specific behavior of each strain.

Relationships among Indicators of Metabolism, Mammary Health and the Microbiomes of Periparturient Holstein Cows

Simple Summary

Parturition is the most important physiological event in the lifecycle of dairy cows; it mediates changes in the microbiota composition. However, the complete picture of the dynamics of these phenomena and how they affect health and metabolism is unknown. This study documents the composition of the microbiota in the mammary gland, on reproductive surfaces and those associated with the rectum immediately after parturition. The microbiomes of different maternal niches were different, as predicted by their different functional roles in cows. Based on the results of this research, the conclusion that the microorganisms that colonize different mucosal tissues of cows were linked to the state of systemic energy metabolism and had an impact on the health of the mammary gland cows following calving was drawn.

Abstract

During the period called “transition”, from the ceasing of milk production to the reestablishment of full milk production, it is postulated that the microbiota of cows undergo changes in composition driven by the fluxes in systemic energetics and that these changes appear to impact the health of cows. The primary objective of this study was to document the make-up of the microbiota in the mammary gland compared with those in the vagina and in feces in an attempt to determine any correlations between the composition of the microbiota, the impact of blood indicators of energetic metabolites and the health of the mammary gland at the time of calving. Samples were collected from 20 Holstein dairy cows immediately following calving to assess their general health and measure the microbiomes associated with each cow using 16S rRNA sequencing. The results indicated that the microbiomes found within each maternal niche were different. A set of significant negative associations between the blood energetic biomarkers (NEFAs, BHB, triglycerides and cholesterol) and the taxa Pseudomonas, Christensenellaceae and Methanobrevibacter were observed in this study. In contrast, Escherichia and Romboutsia were positively correlated with the same energetic metabolites. Therefore, it was concluded that there appears to be a set of relationships between the microorganisms that colonize several niches of cows and the sufficiency of systemic energy metabolism. Furthermore, both the microbiome and energy dynamics impact the health of the mammary gland of the host.

Saponin-adjuvanted recombinant vaccines containing rCP00660, rCP09720 or rCP01850 proteins against Corynebacterium pseudotuberculosis infection in mice

PURPOSE

rCP01850, rCP09729 and rCP00660 proteins from Corynebacterium pseudotuberculosis, predicted as the three best targets to be used in vaccines against Caseous Lymphadenitis in mature epitope density (MED) analysis were tested as vaccinal targets in association to saponin as adjuvant.

METHODOLOGY

rCP00660, rCP09720 and rCP01850 were expressed in E. coli and purified for immunization assay. Balb/c mice were divided into five groups of sixteen animals each. G1 was injected with saline solution (0.9% NaCl), G2 with saponin, G3, G4 and G5 with, respectively, rCP00660, rCP09720 and rCP01850 added by saponin. Two doses were administered within a 21-days interval, and blood samples were collected for IgG quantification. Twenty-one days after the last immunization, ten mice in each group were challenged with virulent C. pseudotuberculosis MIC-6 strain, and mortality was recorded for 40 days. Meanwhile six mice in each group were used for cytokine quantification by qPCR.

RESULTS

G2, G3, G4 and G5 presented protection rates of 10, 30, 40 and 60%, respectively. In spite of levels of total IgG were higher in G4 and G5, production of IgG2a was higher than IgG1 for G5. G3, G4 and G5 presented significant high IFN-γ levels, however, only G5 showed high TNF-α while G3 and G4 showed high IL-17.

CONCLUSION

rCP01850 added by saponin was able to protect efficiently mice against C. pseudotuberculosis challenge, and to induce high IgG, IFN-γ and TNF-α levels. In spite of rCP00660 and rCP09720 had not same adequate protection levels, significant IgG, IFN-γ, and IL-17 levels and further studies aiming to improve protection rates should be conducted.

Effect of prophylactic use of tulathromycin on gut bacterial populations, inflammatory profile and diarrhea in newborn Holstein calves

This objective of this study was to evaluate the use of tulathromycin on the timing of appearance and number of four indicator organisms representing the gastrointestinal microbial community, the incidence of diarrhea and a measure of the systemic inflammatory profile in Holstein heifers. Twenty-six Holstein heifer calves were distributed between receiving (ATB+) or not receiving (ATB-) tulathromycin at a dose of 2.5 mg/kg by 12 h of age. Samples from the calves were collected at six times during the neonatal period. Stool samples were used to determine the dry matter content and quantitative analysis of specific indicator bacterial populations. Samples of whole blood and serum were collected to determine the total number of neutrophils, the number of CD62L+ neutrophils, quantity of haptoglobin, and to allow for ex vivo measurement of reactive oxygen species. A higher frequency of diarrhea was detected in the ATB+ calves (84.6%) than ATB- (53.8%) on days 13-15 (P = 0.084). ATB- calves had a greater number of Bifidobacterium in stool on day 3-5 (P = 0.002), and on days 7-9 (P = 0.018). The ATB+ calves tended to have a higher number of Escherichia coli in stool on days 20-23 and days 27-30 (P = 0.052 and P = 0.072). Both the total number of neutrophils (P = 0.013) and the capacity for ROS production was higher in ATB- (P = 0.038) than ATB+ calves at all points tested. ATB+ calves had higher levels of haptoglobin (P = 0.032) on days 13-15. Administration of tulathromycin appeared to negatively impact the establishment of a normal microbiome and to modulate the development of innate immune function.

Cell wall glycolipids from Corynebacterium pseudotuberculosis strains with different virulences differ in terms of composition and immune recognition

Caseous lymphadenitis (CLA) is an infectious disease caused by Corynebacterium pseudotuberculosis in small ruminants and is characterized by the development of granulomas in the lymph nodes, spleen, liver, and lungs. Although little is known about the host-pathogen relationship of this bacterium, it was previously reported that the pathogen's lipids are important for its taxonomic classification and survival inside macrophages. However, there are no studies regarding the composition of these molecules. In this study, cell wall glycolipids from two C. pseudotuberculosis strains presenting different virulence profiles were purified and its composition was characterized. A difference was observed between the electrophoretic and chromatogram profiles for cell wall components from the two strains, mainly among molecules with low molecular weights. IgM from sheep with acute CLA recognized antigens with an estimated molecular weight of 11 kDa of the low-pathogenicity strain, while low-molecular weight antigens from the high-pathogenicity strain presented a lower recognition by these antibodies. Mass spectrometry analysis showed that the cell wall of the high-pathogenicity strain contained glycolipids with high amounts of unsaturated fatty acids and glycerophosphoinositols, which may contribute to the capacity of this strain to cause severe disease. In conclusion, it is indicated that cell wall non-protein antigens can play a key role in C. pseudotuberculosis virulence.

Influence of feeding fresh colostrum from the dam or frozen colostrum from a pool on indicator gut microbes and the inflammatory response in neonatal calves

The aim of this study was to evaluate the capacity of cells from colostrum to modulate the intestinal microbial colonization, the activity of the inflammatory response, and for their influence on the development of diarrheal disease in calves. Twenty calves were distributed into two groups: COL+ (n = 10) receiving fresh whole colostrum; COL- (n = 10) receiving pooled frozen colostrum, containing no viable cells. All assessments were made before colostrum intake (D0), the next day (D2), and weekly on the 7th (D7), 14th (D14), 21st (D21) and 28th (D28) day of age. Diarrhea was assessed using a fecal score, and the systemic inflammatory status was assessed using a combination of temperature, anemia, total serum iron level, total haptoglobin concentration and the need for systemic antimicrobial treatment. The number of indicator bacteria present in the fecal population was estimated using qPCR. However, COL- calves presented more frequent signs of systemic inflammatory response including, fever at D7 (P = 0.011); indicator haptoglobin levels on D7 and D14, and lower levels of iron on D7, D14. Anemia was detected more often in the COL- calves on D21 (P = 0.043) and D28 (P = 0.016). COL- calves had a 1.66 greater chance of having elevated haptoglobin and a 1.8 greater chance of needing treatment with antimicrobials than COL+. A lower number of DNA copies of Clostridium perfringens were detected in COL+ calves on D2 (P = 0.088) and D7 (P = 0.040). Similarly, a low number of DNA copies was observed for Escherichia coli and Lactobacillus spp. (P = 0.012) in the fecal samples of COL+ calves on D7.

Assessment of the acid phosphatase CP01850 from Corynebacterium pseudotuberculosis in DNA and subunit vaccine formulations against caseous lymphadenitis

ABSTRACT The target cp1002_RS01850 from Corynebacterium pseudotuberculosis was used to construct a DNA and recombinant subunit vaccine against caseous lymphadenitis. Recombinant protein rCP01850 was expressed in Escherichia coli using pAE vector, and DNA vaccine was engineered with pTARGET vector. BALB/c mice were divided in five groups containing eight animals each, inoculated with: pTARGET/cp01850 as DNA vaccine (G1); rCP01850 plus Al (OH)3 as recombinant subunit vaccine (G2); pTARGET/cp01850 and a boost with rCP01850 plus Al (OH)3 (G3); pTARGET (G4); or Al (OH)3 (G5). Mice were inoculated and blood samples were collected on days 0, 21, and 42 for the analysis of total IgG, IgG1 and IgG2a by ELISA. In each group, five animals were challenged with Mic-6 C. pseudotuberculosis strain, and three were used for cytokine quantification by qPCR. Although no group has been protected by vaccines against lethal challenge, G2 showed an increase in the survival rate after challenge. Significantly higher levels of IL-4, IL-12, IFN-γ, total IgG, IgG1 and IgG2a were also detected for G2, evidencing a mixed Th1/Th2 immunological profile. In conclusion, despite no protection level provided by different vaccinal strategies using cp1002_RS01850 from C. pseudotuberculosis, G2 developed a Th1/Th2 immune response with an increase in survival rate.

The combination of Corynebacterium pseudotuberculosis recombinant proteins rPLD, rCP01850 and rCP09720 for improved detection of caseous lymphadenitis in sheep by ELISA

Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis (CLA), a chronic disease of sheep and goats. Current methods for CLA diagnosis cannot identify all infected animals; therefore, the development of an improved diagnosis is essential. We evaluated recombinant phospholipase D (rPLD) protein individually or combined with rCP01850 or rCP09720 proteins for the detection of CLA in sheep. A total of 40 positive and 25 negative sera samples were analysed by ELISA using the recombinant proteins. ELISA using rPLD (E1), rPLD+rCP01850 (E2) and rPLD+rCP09720 (E3) showed 90, 92.5 and 97.5 % sensitivity and 92, 72 and 92 % specificity, respectively. The area under the receiver operating characteristic curves for E1, E2 and E3 was 0.925, 0.882 and 0.990, respectively. ELISA using rPLD +rCP09720 demonstrated the best sensitivity and specificity. Thus, the combination of these recombinant proteins in indirect ELISA has the potential for the diagnosis of CLA in sheep.

Effects of 3 Different Commercial Vaccines Formulations against BVDV and BHV-1 on the Inflammatory Response of Holstein Heifers

After vaccination, vaccine components must activate the immune response, but the ideal vaccine should not result in undesirable effects in cattle. The aim of this study was to evaluate the inflammatory and humoral responses and adverse reactions induced by three adjuvanted commercial vaccines against bovine viral diarrhea virus (BVDV) and bovine herpesvirus 1 (BHV-1). Holstein heifers (n = 35) were divided into four groups by adjuvant compounds: Vaccine A (Alum; n = 9), Vaccine B (Oil-in-water; n = 10), Vaccine C (Amphigen/Quil A cholesterol and dimethyl-dioctadecyl ammonium (DDA) bromide (QAD; n = 10), and Control (n = 6). Heifers were assessed at 0 h, 6, 24, 48, 72 and 168 h post-vaccination; serology was evaluated at first dose (D0), booster (D21) and D42. Heifers vaccinated with Vaccine B (p = 0.0001) and C (p = 0.0001) had a more intense local reaction, while there was a higher rectal temperature detected in heifers vaccinated with Vaccine C (p = 0.020). There was greater systemic reaction observed for heifers vaccinated with Vaccines B and C at 48 h (p = 0.002) after a second dose. Clinical pathology parameters [white blood count (WBC) (p = 0.001), neutrophils (p = 0.0001) and haptoglobin concentrations (p = 0.0001)] were higher in animals vaccinated with Vaccine C. Neutralizing Abs against BVDV type 1 strains, NADL and Singer, were detected in animals vaccinated with Vaccines A or C at D42, while BVDV-2 antibodies were detected only in animals vaccinated with Vaccine C. A BHV-1 antibody was detected in all three vaccine groups (Vaccines A, B or C) at day 42 (21 days post booster vaccination). The findings of this research were based on three different commercial laboratory formulations and also according to the conditions which the study was conducted. In this context, vaccine containing mineral oil or Amphigen/QAD presented greater local reactivity and induced a significant systemic inflammatory response. Vaccinated heifers with Alum and Amphigen/QAD commercial vaccines enhanced humoral immune response against BVDV and BHV-1.

Recombinant M. bovis BCG expressing the PLD protein promotes survival in mice challenged with a C. pseudotuberculosis virulent strain

The aim of this study was to evaluate the survival of mice inoculated with M. bovis BCG Pasteur recombinant expressing the PLD protein and challenged with a C. pseudotuberculosis virulent strain. Four groups were immunized with a sterile 0.9% saline solution (G1), 10⁶ CFU of M. bovis BCG Pasteur (G2), 10⁶ CFU of M. bovis BCG/pld (G3) or 10⁶ CFU of M. bovis BCG/pld with a booster with rPLD (G4) and challenged with 10⁴ CFU of C. pseudotuberculosis MIC-6 strain. The highest survival rate of 88% was observed in G4, followed by 77% in G3 and 66% in G2. A significant statistical difference was observed in the levels of cytokines IFN-γ and IL-10 in vaccinated groups (G3 and G4) when compared with the control group (G1) (p < 0.05). The results seem promising as the recombinant vaccine elicited a cellular immune response and provided significant survival after a high virulent challenge.

Association of Corynebacterium pseudotuberculosis recombinant proteins rCP09720 or rCP01850 with rPLD as immunogens in caseous lymphadenitis immunoprophylaxis

Caseous lymphadenitis (CLA) is a chronic disease responsible for significant economic losses in sheep and goat breeding worldwide. The treatment for this disease is not effective, and an intense vaccination schedule would be the best control strategy. In this study, we evaluated the associations of rCP09720 or rCP01850 proteins from Corynebacterium pseudotuberculosis with recombinant exotoxin phospholipase D (rPLD) as subunit vaccines in mice. Four experimental groups (10 animals each) were immunized with a sterile 0.9% saline solution (G1), rPLD (G2), rPLD + rCP09720 (G3), and rPLD + rCP01850 (G4). The mice received two doses of each vaccine at a 21-day interval and were challenged 21 days after the last immunization. The animals were evaluated daily for 40 days after the challenge, and mortality rate was recorded. The total IgG production level increased significantly in the experimental groups on day 42 after the first vaccination. Similarly, higher levels of specific IgG2a were observed in experimental groups G2, G3, and G4 compared to the IgG1 levels on day 42. G4 showed a significant (p < .05) humoral response against both antigens of the antigenic formulations. The cellular immune response induced by immunization was characterized by a significant (p < .05) production of interferon-γ compared to that in the control, while the concentrations of interleukin (IL)-4 and IL-12 were not significant in any group. A significant increase of tumor necrosis factor was observed only in G4. The survival rates after the challenge were 30% (rPLD), 40% (rPLD + rCP09720), and 50% (rPLD + rCP01850). Thus, the association of rCP01850 with rPLD resulted in the best protection against the challenge with C. pseudotuberculosis and induced a more intense type 1 T-helper cell immune response.

Humoral and cellular immune responses in mice against secreted and somatic antigens from a Corynebacterium pseudotuberculosis attenuated strain: Immune response against a C. pseudotuberculosis strain

Background

Corynebacterium pseudotuberculosis is the etiologic agent of caseous lymphadenitis (CL), a chronic disease that affects goats and sheep. CL is characterized by the formation of granulomas in lymph nodes and other organs, such as the lungs and liver. Current knowledge of CL pathogenesis indicates that the induction of humoral and cellular immune responses are fundamental to disease control. The aim of this study was to evaluate the humoral and cellular immune responses in BALB/c mice inoculated with a C. pseudotuberculosis strain isolated in the state of Bahia, Brazil.

Results

The lymphocyte proliferation and in vitro production of IFN-γ, IL-4, IL-10, IL-12 and nitric oxide by spleen cells stimulated with secreted and somatic antigens from the studied strain were evaluated. IgG subclasses were also analyzed. Results showed a significant increase of Th1-profile cytokines after 60 days post-inoculation, as well as an important humoral response, represented by high levels of IgG2a and IgG1 against C. pseudotuberculosis.

Conclusion

The T1 strain of C. pseudotuberculosis was shown to induce humoral and cellular immune responses in BALB/c mice, but, even at a dosage of 1x10⁷ CFU, no signs of the disease were observed.

Influence of Corynebacterium pseudotuberculosis infection on level of acute phase proteins in goats

Background

Goat caseous lymphadenitis (CLA) is a chronic disease caused by Corynebacterium pseudotuberculosis. However, there is paucity of data about goat’s acute phase response during the course of CLA. This study was conducted to investigate the response of acute phase proteins, mainly haptoglobin (Hp), serum amyloid A (SAA) and the negative acute phase response, especially albumin after an experimental challenge of C. pseudotuberculosis and phospholipase D (PLD) in Cross bred Boer goats.

Results

Serum Hp concentration in goats challenged with C. pseudotuberculosis (inoculated with 1x10⁹ cfu subcutaneously) showed a significant increase, 5 fold in males (0.98 ± 0.12 mg/ml) and 3 fold in females (0.66 ± 0.12 mg/ml) compared to the control (0.2 ± 0.02 mg/ml). Challenge with PLD (1 ml/20 kg body weight intravenously) also showed significant increase, 4 fold in males and females (0.89 ± 0.11 mg/ml; 0.82 ± 0.12 mg/ml) respectively compared to the control (0.2 ± 0.02 mg/ml). Albumin concentration showed a significant decrease in both treated groups compared to the control. There were no significant changes in SAA concentration between challenged and control goats.

Conclusions

There was a significant response by Hp to C. pseudotuberculosis infection and PLD challenge. This was supported by the early acute response in which Hp was detected before CLA lesions were developed. Therefore, it concluded that C. pseudotuberculosis and PLD can influence the level of acute phase proteins in goats.

Complete Genome Sequence of Corynebacterium pseudotuberculosis Viscerotropic Strain N1

We present the complete genome sequence of Corynebacterium pseudotuberculosis strain N1. The sequencing was performed with the Ion Torrent Personal Genome Machine system. The genome is a circular chromosome with 2,337,845 bp, a G+C content of 52.85%, and a total of 2,045 coding sequences, 12 rRNAs, 49 tRNAs, and 58 pseudogenes.