Expression of cytokine and apoptosis-related genes in bovine peripheral blood mononuclear cells stimulated with Brucella abortus recombinant proteins

Salivary heat shock protein 70 as a potential non-invasive biomarker of environmental thermal stress in dairy cattle

The present study aims to explore the potential biomarker application of salivary heat shock 70 kDa protein in detecting thermal stress in dairy animals noninvasively. The study spans for 45 days during the mid-summer season (April-May), involving twelve multiparous non-pregnant adult Jersey crossbred cows by randomly allocating them into groups (six animals in each group). The control animals were maintained in the shed, whereas the thermal stress group animals were exposed to environment heat between 10:00 h to 16.00 h and they were feed and watered ad libitum. During the experimental period, the hematobiochemical, physiological, behavioural, nutritional and production responses were recorded and the whole blood and saliva were collected fortnightly. Results revealed significant increase in WBC, AST, ALP, blood urea nitrogen, triglycerides, cholesterol, HDL, blood and salivary cortisol, respiratory rate, rectal temperature, skin temperature of neck, lumbar and forelimb regions, standing time, salivary and blood HSP70 mRNA expression and their protein concentrations in heat stressed animals. In addition, RBC, haemoglobin, MCV, PCV, platelet, platelet-large cell ratio (PLCR), lying time, feed intake, milk yield and rumination time were significantly decreased in thermally stress animals. Furthermore, ROC curve analysis revealed the biomarker potential of these significantly altered parameters with 100% sensitivity and specificity for predicting environmental heat stress in dairy cows with AUC and Youden's - index of 1.00 except platelet. Moreover, salivary HSP70 demonstrated significant correlation with these biomarkers. Noteworthily, salivary HSP70 also exhibited strong association with blood HSP70 and salivary cortisol. Furthermore, salivary HSP70 revealed 100% sensitivity and specificity in discriminating the dairy cattle succumbed to heat stress from healthy. In conclusion, the present study provides a newer insight into the multifaceted roles of HSP70 and identified salivary heat shock 70 kDa protein as a potential, reliable and more sensitive non-invasive biomarker for identifying environmental heat stress in dairy cattle.

Expression of cytokine and Apoptosis-Associated genes in mice bone Marrow-Derived Macrophages stimulated with Brucella recombinant type IV secretion effectors

BACKGROUND

Brucellosis is an economically important infectious caused by most commonly by Brucella. Detection of infected animals at the early stage is important for controlling the disease. The diagnostic antigens, usually protein antigens, have attracted much interest. However, the accurate mechanism of immune response is still unknown. The secretory effectors (BPE005, BPE275, and BPE123) of the type IV secretion system (T4SS) were involved in the intracellular circulation process of Brucella and the immune responses of the host.

METHODS

Genes encoding three B. abortus effector proteins (BPE005, BPE275, and BPE123) of T4SS were cloned and the recombinant proteins were expressed and purified. The purified recombinant proteins were named rBPE005, rBPE275 and rBPE123. Then, the expressions of Th1- and Th2-related cytokine genes were analyzed in mice bone marrow-derived macrophages (BMDMs) after stimulation with rBPE005, rBPE275, and rBPE123. Furthermore, four apoptosis-associated genes (Caspase-3, Caspase-8, Bax, and Bcl-2) were also detected to explore the damage of the proteins to the cells.

RESULTS

Expressions of all Th1- and Th2-related cytokine genes were induced with three proteins, and different cytokine expression patterns induced by each protein depend on the stimulation time and dose of protein. However, expressions of apoptosis-related genes did not change.

CONCLUSION

These results showed that the secreted antigens of Brucella induced an immune reaction via the production of Th1- and Th2-type cytokines in BMDMs without exerting any damage on the cells.

Evasion of host defense by Brucella

Brucella , an adept intracellular pathogen, causes brucellosis, a zoonotic disease leading to significant global impacts on animal welfare and the economy. Regrettably, there is currently no approved and effective vaccine for human use. The ability of Brucella to evade host defenses is essential for establishing chronic infection and ensuring stable intracellular growth. Brucella employs various mechanisms to evade and undermine the innate and adaptive immune responses of the host through modulating the activation of pattern recognition receptors (PRRs), inflammatory responses, or the activation of immune cells like dendritic cells (DCs) to inhibit antigen presentation. Moreover, it regulates multiple cellular processes such as apoptosis, pyroptosis, and autophagy to establish persistent infection within host cells. This review summarizes the recently discovered mechanisms employed by Brucella to subvert host immune responses and research progress on vaccines, with the aim of advancing our understanding of brucellosis and facilitating the development of more effective vaccines and therapeutic approaches against Brucella .

Expression profiling of cytokine genes in peripheral blood mononuclear cells from Anaplasma marginale infected and healthy cattle

In this study, changes in expression profiles of genes encoding 14 cytokines (IL1A, IL1B, IL2, IL4, IL6, IL8, IL10, IL12A, IL12B, IL16, IFNA, IFNB, TGFB1, and TNFA) were investigated amongst six Anaplasma marginale infected and six healthy crossbred cattle. Health status of the animals was determined based on clinical signs, blood smear examination and molecular detection using A. marginale-specific primers. Total RNA was isolated from the peripheral blood mononuclear cells of the infected animals as well as the healthy controls, which was further reverse transcribed to cDNA. Primers for real time PCR were designed using Primer3 software and the results were analyzed by the 2-ΔΔCt method with RPS15 and GAPDH as the reference genes. The expression levels of IL1A, IL1B, IL6, IL10, IL12A, IL12B, and TNFA varied significantly between the two groups, with higher expression in the infected cattle. The transcript abundance of IL4, IL16, and TGFB1 did not vary between the diseased and healthy animals. The expression of IL2 and IL8 was higher in the healthy animals, but the results were non-significant. Taken together, this study provides evidence for difference in expression of cytokine genes in response to anaplasmosis in crossbred cattle.

The mechanism of chronic intracellular infection with Brucella spp

Globally, brucellosis is a widespread zoonotic disease. It is prevalent in more than 170 countries and regions. It mostly damages an animal's reproductive system and causes extreme economic losses to the animal husbandry industry. Once inside cells, Brucella resides in a vacuole, designated the BCV, which interacts with components of the endocytic and secretory pathways to ensure bacterial survival. Numerous studies conducted recently have revealed that Brucella's ability to cause a chronic infection depends on how it interacts with the host. This paper describes the immune system, apoptosis, and metabolic control of host cells as part of the mechanism of Brucella survival in host cells. Brucella contributes to both the body's non-specific and specific immunity during chronic infection, and it can aid in its survival by causing the body's immune system to become suppressed. In addition, Brucella regulates apoptosis to avoid being detected by the host immune system. The BvrR/BvrS, VjbR, BlxR, and BPE123 proteins enable Brucella to fine-tune its metabolism while also ensuring its survival and replication and improving its ability to adapt to the intracellular environment.

Effect of co-positivity for brucellosis and tuberculosis on milk yield and fertility of Holstein cows

This study aimed to determine whether cows detected as tuberculosis (bTB) reactors and seropositive to brucellosis (bBR), as well as co-positive to bBR and bTB (bBR-bTB) and with a complete lactation before slaughter, were associated with reduced milk production and fertility. A total of 8068 productive and reproductive records of high-yielding Holstein cows from a single large dairy herd with a high prevalence of bTB and bBR were collected from 2012 to 2015. Lactation derived either from calving (n = 6019) or hormonally induced lactation (n = 2049), and all cows received growth hormone throughout lactation. For cows not induced into lactation, pregnancy rate to first service for healthy cows (C; 26.6%) was higher (P < 0.01) than bBR (15.2%), bTB (15.8%), and bBR-bTB (1.3%) cows. For induced cows, pregnancy rate to first service did not differ significantly among C, bBR, and bTB (14.5-17.3%) cows, but the percentage success of first service was extremely low (1.3%; P < 0.01) in bBR-bTB cows. Services per pregnancy (only pregnant cows) were lowest for C (3.3 ± 2.9; P < 0.01) and highest (6.4 ± 3.4) for bBR-bTB non-induced cows. This variable was lowest for C (2.9 ± 2.5; P < 0.01) and highest for bBR-bTB non-induced cows (6.3 ± 3.1). Pregnancy rate to all services did not differed for C (79.5%), bBR (76.7%), and bTB (75.9%) but was lower (58.9%; P < 0.01) for bBR-bTB non-induced cows. For induced cows this variable was highest for bBR (53.3%) and lowest for bBR-bTB (34.1%; P < 0.01) non-induced cows. 305-d milk production was increased by 4%, and total milk yield by 7% in TB-positive cows compared to that of the negative cows non-induced hormonally into lactation. This study showed the negative impact of the co-positivity for bTB and bBR on the reproductive efficiency of Holstein cows, although positive bTB and bBR tests enhanced milk yield.

Establishment and Expression of Cytokines in a Theileria annulata-Infected Bovine B Cell Line

This study aimed to establish a pure single-cell Theileria annulata-infected B cell line for the assessment of cytokine production in transformed and lipopolysaccharide (LPS)-stimulated cells. Several studies have aimed to identify cell surface markers in T. annulata-transformed cells; however, no information on cytokine production in these cells is available. To investigate the potential of the transformed cells to produce cytokines and their potential responses to antigen-stimulation, we purified mature B cells (CD21) from the whole blood of cattle experimentally infected with the T. annulata Kashi strain by magnetic separation. The purity and specificity of the established cell line was assessed by the identification of specific cell surface markers (CD21, IgM, and WC4) by flow cytometry analysis. The transcript levels of the cytokines IL1A, IL1B, IL2, IL4, IL6, IL8, IL10, IL16, LTA, TGFB1, TNFA, IFNA, and IFNB in transformed, buparvaquone (BW720c)-treated cells, and antigen-stimulated cells were analyzed by quantitative polymerase chain reaction (qPCR) using cDNA from these cells. A T. annulata-infected bovine B cell line was successfully established with a purity of ~98.8% (CD21). IL4 and IL12A were significantly (p < 0.01) upregulated in the transformed cells. In BW720c-treated transformed cells, IL12B, TGFB1, and IFNB were significantly (p < 0.01) upregulated. Notably, no significant (p > 0.05) upregulation of cytokines was observed in LPS-stimulated transformed cells. Moreover, IL1A, IL1B, IL8, and IL16 were significantly (p < 0.01) upregulated in LPS-stimulated B cells. Our data signify the potential use of this cell line for cytokine production, observance of immunoglobulins, and production of an attenuated vaccine against tropical theileriosis.

Lipopolysaccharide mediates immuno-pathological alterations in young chicken liver through TLR4 signaling

BACKGROUND

Lipopolysaccharide (LPS) induces acute liver injury and the complex mechanisms include the activation of toll like receptor 4 (TLR4) signaling pathway in many species. However, immuno-pathological changes during TLR4 signaling under LPS stress in acute liver injury is poorly understood in avian species. The present investigation was therefore carried out to evaluate these alterations in TLR4 signaling pathway during acute liver injury in young chickens.

RESULTS

After intraperitoneal injection of LPS or saline, liver samples were harvested at 0, 2, 6, 12, 24, 36, 72 and 120 h (n = 6 at each time point) and the microstructures were analyzed by hematoxylin and eosin (H&E) staining. Alanine aminotransferase (ALT) and caspase-3 enzyme activity was assessed by enzyme-linked immunosorbent assay (ELISA). Proliferative cell nuclear antigen (PCNA), single stranded DNA (ssDNA) and TLR4 protein expressions were determined by immunohistochemistry. Gene expressions of PCNA, caspase-3, caspase-8, TLR4 and its downstream molecules were analyzed by quantitative polymerase chain reaction (qPCR). LPS injection induced significantly higher ALT activity, severe fatty degeneration, necrotic symptoms, ballooning degeneration, congestion, enhanced inflammatory cell infiltration in liver sinusoids, decreased proliferation, increased apoptosis and significant up-regulation in TLR4 and its downstream molecules (MyD88, NF-κB, TNF-α, IL-1β and TGF-β) expression at different time points.

CONCLUSIONS

This study indicated that TLR4 signaling and its downstream molecules along with certain cytokines play a key role in acute liver injury in young chickens. Hence, our findings provided novel information about the histopathological, proliferative and apoptotic alterations along with changes in ALT and caspase-3 activities associated with acute liver injury induced by Salmonella LPS in avian species.

Brucella Melitensis 16M Regulates the Effect of AIR Domain on Inflammatory Factors, Autophagy, and Apoptosis in Mouse Macrophage through the ROS Signaling Pathway

Brucellosis is a highly contagious zoonosis caused by Brucella. Brucella can invade and persist inside host cells, which results in chronic infection. We constructed AIR interference and overexpression lentiviruses to acquire AIR interference, overexpression, and rescue stable expression cell lines. We also established a Brucella melitensis 16M-infected macrophage model, which was treated with either the vehicle control or NAC (ROS scavenger N-acetylcysteine (NAC) for 0, 3, 6, 12, and 24 h. Confocal laser microscopy, transmission electron microscopy, fluorescence quantitative PCR, flow cytometry, ELISA, and Western blot were used to detect inflammation, cell autophagy and apoptosis-related protein expression levels, ROS levels, and the distribution of mitochondria. It was found that after interference and overexpression of AIR, ROS release was significantly changed, and mitochondria became abnormally aggregated. B. melitensis 16M activated the NLRP3/AIM2 inflammatory complex, and induced RAW264.7 cells to secrete IL-1β and IL-18 through the ROS pathway. B. melitensis 16M also altered autophagy-related gene expression, increased autophagy activity, and induced cell apoptosis through the ROS pathway. The results showed that after B. melitensis 16M infection, ROS induced apoptosis, inflammation, and autophagy while AIR inhibited autophagosome maturation and autophagy initiation. Autophagy negatively regulated the activation of inflammasomes and prevented inflammation from occurring. In addition, mitophagy could promote cell apoptosis.