Modulation of the pro-inflammatory molecules E-selectin and TNF-α gene transcription in Eimeria ninakohlyakimovae -infected primary caprine host endothelial cells

MicroRNA expression profile of chicken jejunum in different time points Eimeria maxima infection

Coccidiosis stands as a protozoan disease of notable economic impact, characterized by an intracellular parasite that exerts substantial influence over poultry production. This invasion disrupts the integrity of the enteric mucosa, leading to the emergence of severe lesions and diminishing the efficiency of feed utilization in chickens. MicroRNA (miRNA) are short, non-coding RNA molecules with approximately 21-24 nucleotides long in size that play essential roles in various infectious diseases and inflammatory responses. However, the miRNA's expression patterns and roles in the context of Eimeria maxima infection of chicken intestines remain unclear. miRNA sequencing was employed to assess the miRNA expression profile in chicken jejunum during E. maxima infection. In this study, we analyzed miRNA expression profiles related to the host's immune response in the chicken jejunum during E. maxima infection. At 4 days infection and control (J4I versus J4C), 21 differentially expressed miRNAs in the jejunum were identified, comprising 9 upregulated and 12 downregulated miRNAs. Furthermore, in the jejunum, at 7 days infection and control (J7I versus J7C) groups, a total of 35 significantly differentially expressed miRNAs were observed, with 13 upregulated and 22 downregulated miRNAs. The regulatory networks were constructed between differentially expressed miRNA and mRNAs to offer insight into the interaction mechanisms between chickens and E. maxima coccidian infection. Furthermore, within the comparison group, we obtained 946, 897, and 281 GO terms that exhibited significant enrichment associated with host immunity in the following scenarios, J4I vs. J4C, J7I vs. J7C, and J4I vs. J7I, respectively. The KEGG pathway analysis indicated notable enrichment of differentially expressed miRNAs in the jejunum, particularly in J4I vs. J4C; enriched pathways included metabolic pathways, endocytosis, MAPK signaling pathway, regulation of actin cytoskeleton, and cytokine-cytokine receptor interaction. Moreover, in J7I vs. J7C, the KEGG pathway was significantly enriched, including metabolic pathways, protein processing in the endoplasmic reticulum, ubiquitin-mediated proteolysis, and FoxO signaling pathway. A comprehensive understanding of the host genetic basis of resistance with a combination of time-dependent infection to the Eimeria parasite is crucial for pinpointing resistance biomarkers for poultry production.

Micro-RNA expression profile of chicken small intestines during Eimeria necatrix infection

Eimeria necatrix is a high pathogenic pathogen second to Eimeria tenella causing chicken coccidiosis. However, the precise underlying molecular mechanisms of interaction between E. necatrix and chickens are not fully understood. Accumulating evidences suggest that micro-RNAs (miRNAs) play pivotal regulatory roles in various diseases, including parasitic diseases. In the present study, the expression profile of miRNAs in Hy-line variety white chicken small intestines infected with E. necatrix was studied by using deep sequencing. A total of 35 miRNAs (including 16 significantly upregulated and 19 significantly downregulated miRNAs) were significantly differentially expressed (DE) in infected tissues at 108 h post-infection (pi). Real-time polymerase chain of 10 miRNAs (including 5 upregulated and 5 downregulated) randomly selected successfully confirmed the effectiveness of deep sequencing. Target prediction showed that 4,568 mRNAs could be regulated by 21 (including 12 upregulated and 9 downregulated) of 35 differentially expressed miRNAs. Functional analysis indicated that target genes of these differentially expressed miRNAs would be involved in pathways related to infection of E. necatrix, including cell differentiation, adhesion, proliferation, and apoptosis (e.g., MAPK signaling pathway and PPAR signaling pathway). To our best knowledge, this is the first study on the miRNA expression profile of small intestines during E. necatrix infection, and the findings in the present study suggested that these DE miRNAs would play important regulatory role in the interaction between E. necatrix and chicken intestines.

Preliminary studies on in vitro methods for the evaluation of anticoccidial efficacy/resistance in ruminants

Ovine Eimeria spp. infections cause increased mortality, reduced welfare and substantial economic losses, and anticocccidials are important for their control. Recent reports of anticoccidial resistance against ovine Eimeria spp. necessitate the development of in vitro methods for the detection of reduced anticoccidial efficacy, especially since the in vivo methods are both expensive, time consuming and requires the use of otherwise healthy animals. The aim of the present study was therefore to approach a preliminary standardization of in vitro assays for evaluation of the efficacy of the most commonly used anticoccidials in ruminants. For this purpose, apart from the evaluation of inhibition of oocyst sporulation, most effort was concentrated on assessment of the capacity of the different anticoccidials to inhibit both the invasion and further development (up to the first schizogony) of E. ninakohlyakimovae sporozoites in bovine colonic epithelial cells (BCEC). For this purpose, infected cultures were monitored 1, 8 and 15 days post infection to determine the infection rate, number of immature schizonts and number, size and appearance of mature schizonts, respectively. No clear inhibitory effect was found with any of the anticoccidial formulations tested, and we could not identify why there were no measurable effects from the different anticoccidials. Despite the lack of positive results, further investigations should be encouraged, as this could decrease the need for animal experiments and could be used in the initial assessment of anticoccidial efficacy of new drugs.

A newly described strain of Eimeria arloingi (strain A) belongs to the phylogenetic group of ruminant-infecting pathogenic species, which replicate in host endothelial cells in vivo

Coccidiosis caused by Eimeria species is an important disease worldwide, particularly in ruminants and poultry. Eimeria infection can result in significant economic losses due to costs associated with treatment and slower growth rates, or even with mortality of heavily infected individuals. In goat production, a growing industry due to increasing demand for caprine products worldwide, coccidiosis is caused by several Eimeria species with E. arloingi and E. ninakohlyakimovae the most pathogenic. The aims of this study were genetic characterization of a newly isolated European E. arloingi strain (A) and determination of phylogenetic relationships with Eimeria species from other ruminants. Therefore, a DNA sequence of E. arloingi strain (A) containing 2290 consensus nucleotides (the majority of 18S rDNA, complete ITS-1 and 5.8S sequences, and the partial ITS-2) was amplified and phylogenetic relationship determined with the most similar sequences available on GenBank. The phylogenetic tree presented a branch constituted by bovine Eimeria species plus E. arloingi, and another one exclusively populated by ovine Eimeria species. Moreover, E. arloingi, E. bovis and E. zuernii, which all replicate in host intestinal endothelial cells of the lacteals, were found within the same cluster. This study gives new insights into the evolutionary phylogenetic relationships of this newly described caprine Eimeria strain and confirmed its close relationship to other highly pathogenic ruminant Eimeria species characterized by macromeront formation in host endothelial cells of the central lymph capillaries of the small intestine.

Molecular epidemiology and point mutations in ITS1 and 18S rDNA genes of Eimeria ninakohlyakimovae and E. christenseni isolated from Indian goats

Epidemiology and molecular characterization of Eimeria was carried in goats reared under semi-arid region of west Uttar Pradesh, India. A total of 1285 faecal samples from different goat breeds (Jamunapari, Jakhrana and Barbari) were examined for presence of Eimerian oocysts over a period of eight months along with faecal oocysts count. All raw data of faecal oocyst counts (FOC) were transformed by log_e (OPG+ 100) before analysis. All fixed effects like breed, age, months of sample collections along with their interaction were considered in analysis. The overall prevalence of Eimeria infection in goats was 73.85%. Breed wise prevalence in Barbari, Jamunapari and Jakhrana breed was 68.62, 79.70 and 72% respectively. Prevalence observed in 2-6M, 6-12M and >12M was as 70.83, 79.88 and 71.74% respectively. Gender wise prevalence as observed in male and female goats was 71.95 and 74.43% respectively. In oocyst per gram (OPG) data analysis the fixed effects like breed, age, months of sample collection and age versus gender interaction had significant effect on log transformed faecal oocysts counts (LFOC). The overall least square means of OPG was 4.673±0.007 (1403OPG). Of the three goat breeds, Jamunapari had highest OPG (2886OPG) compared to Jakhrana (875OPG) and Barbari (523OPG). Mean OPG in 2-6month age goats was significantly higher than the corresponding values in 6-12 and >12months, significant variation was found among monthly OPG means and wet months showed higher faecal oocysts discharge. Nine Eimeria species were identified infecting goats and E. arloingi and E. ninakohlyakimovae were most frequent and predominant species. Molecular characterization for coccidial infection was conducted using two genes i.e. 18S rDNA and ITS-1 genes which amplified 637bp and <500bp (E. ninakohlyakimovae) and >500bp (E. christenseni and E. alijevi) respectively. The ITS1 gene was analysed by sequencing, E. christenseni was found showing nucleotide similarity with E. bovis and E. ellipsoidalis whereas 3' end of the sequence were highly conserved. The ITS1 gene of E. ninakohlyakimovae was found more homologous to E. bovis, E. ellipsoidalis and E. zuernii but for 33rd nucleotide thymidine residue deletion and 5th position G→A mutation. The 18S rDNA sequences of E. ninakohlyakimovae and E. christenseni were studied for evolutionary divergence analysis and maximum divergence was noticed between E. ninakohlyakimovae and E. christenseni (0.0605). The phylogenetic tree showed E. ninakohlyakimovae was placed in same clade with other Eimeria spp. compared, but E. christenseni being placed in a different clade as an out-group.

Besnoitia besnoiti infections activate primary bovine endothelial cells and promote PMN adhesion and NET formation under physiological flow condition

Besnoitia besnoiti is an obligate intracellular and emerging coccidian parasite of cattle that mainly infects host endothelial cells during acute infection. We here analyzed early innate immune reactions of B. besnoiti-infected primary bovine umbilical vein endothelial cells (BUVEC). B. besnoiti infections significantly activated BUVEC since the gene transcripts of several adhesion molecules (P-selectin, intercellular adhesion molecule 1(ICAM-1)), chemokines (CXCL1, CXCL8, CCL5), and of COX-2 were significantly upregulated during in vitro infection. Overall, the highest upregulation of most transcripts was observed at 24 or 48 h post infection (p.i.). Enhanced adhesion molecule expression in infected host cells was confirmed by PMN adhesion assays being performed under physiological flow conditions revealing a significantly increased PMN adhesion on B. besnoiti-infected BUVEC layers at 24 h p.i. Furthermore, we were able to illustrate neutrophil extracellular traps (NETs) being released by PMN under physiological flow conditions after adhesion to B. besnoiti-infected BUVEC layers. The present study shows that B. besnoiti infections of primary BUVEC induce a cascade of pro-inflammatory reactions and triggers early innate immune responses.