Screening and Analysis of Anaplasma marginale Tunisian Isolates Reveal the Diversity of lipA Phylogeographic Marker and the Conservation of OmpA Protein Vaccine Candidate

Molecular Analysis and Bioinformatics Assessment of Full-Length L1 Gene of Bovine Papillomavirus Type-1 as a Potential DNA Vaccine Study

Background: Papillomaviruses (PVs) infect animals and humans and are linked to 27%-30% of cancers. The L1 protein is a cornerstone in bovine PVs (BPVs), being the main components of the viral capsid and playing pivotal roles in infectivity and antigenicity. Objective: The current study aims to characterize the genetic variation in the L1 gene of the BPV, explore in silico the protein structure, predict epitopes, and evaluate the impact of mutation on the epitope conservancy. Methods: Fifty tumor samples were collected from cattle with papilloma lesions from Babylon, Wasit, and Al-Qadisiyah provinces, Iraq. Samples were submitted to PCR to amplify the complete L1 gene. Phylogeny was performed to assess the L1 gene. Various bioinformatics tools were utilized to analyze physicochemical properties, secondary structure of the deduced protein, and predict immunodominant epitopes for B and T cells. Results: BPV DNA was detected in 42 (84%) samples. Sequence analysis of 10 samples revealed that BPV-1 was the predominant type circulating in study regions. Phylogeny demonstrated that analyzed strains were aligned with a distance value of 1%-15% to strains of delta PVs. Amino acid characterization indicated two amino acid mutations compared with reference strain (X02346.1) including SER31/ASN and Ala 55/ASP. The 3D model revealed L1 that formed from hexameric subunits, each subunit with six loops. ALA 55/ASP substitutions are located in the Loop1. The predicted B- and T-cell epitopes showed that L1 protein has highly potent epitopes and can be a promising target for nucleic acid vaccine design to elicit an anti-BPV humeral and cellular immune response. Conclusions: The current investigation has provided crucial insights into BPV-1 type and diversity in the middle provinces of Iraq. These predominant strains have been identified and registered at NCBI for the first time. The amino acid mutations in the L1 protein have been highlighted. The conserved T- and B-cell epitopes that can detect BPV-1 type have been stablished. Finally, this project is the initial phase of creating a DNA-based vaccination for preventative and treatment purposes against BPV-related illnesses.

Molecular identification, risk factor assessment, and phylogenetic analysis of tick-borne pathogens in symptomatic and asymptomatic cattle from South-Eastern Iran

Tick-borne pathogens (TBPs) represent a substantial threat to cattle globally, exerting adverse impacts on production, health, and economic viability. This study delves into the prevalence and implications of TTBPs in cattle sourced from resource-limited smallholder livestock farms situated in southeastern Iran, proximate to Afghanistan and Pakistan. Blood and tick specimens were systematically collected from a cohort of 230 cattle, comprising 150 asymptomatic and 80 symptomatic individuals. Genomic DNA isolated from blood samples underwent rigorous examination for the presence of key TBPs, including Anaplasma marginale, A. phagocytophilum, A. bovis, A. centrale, Babesia bigemina, and Theileria annulata, utilizing multiple genetic markers. Nucleotide sequence analysis facilitated the reconstruction of phylogenetic relationships. The study also evaluated various potential risk factors, such as clinical status, gender, age, breed, tick infestation, and management practices, to elucidate their associations with TTBPs. Among the cattle cohort, a staggering 87.8% (202/230) tested positive for at least one pathogen. Prevalence statistics encompassed A. marginale (72.2%), T. annulata (68.3%), A. phagocytophilum/A. platys-like complex (66.1%), A. centrale (16.7%), B. bigemina (10.0%), and A. bovis (6.1%). Remarkably, mixed infections involving two, three, and four pathogens were detected in 23%, 52.1%, and 2.2% of animals, respectively. Notably, all asymptomatic cattle were positive for at least one TBP. Tick infestation was observed in 62.2% (143/230) of cattle, predominantly caused by Hyalomma anatolicum (82.5%), Rhipicephalus (Boophilus) annulatus (13.1%), and R. sanguineus sensu lato (4.4%). Risk factors linked to TBPs encompassed tick infestation, older age, and crossbred animals. Clinical presentations among symptomatic cattle encompassed fever, anemia, weight loss, anorexia, jaundice, and enlarged superficial lymph nodes. This study underscores the pivotal role of asymptomatic carriers in the propagation of TTBPs within endemic regions. Furthermore, it emphasizes the potential for the implementation of molecular diagnostics to unmask subclinical infections, thereby affording the opportunity for targeted interventions aimed at ameliorating the burden of TTBPs in resource-constrained smallholder dairy farms.

Anaplasma Species in Africa-A Century of Discovery: A Review on Molecular Epidemiology, Genetic Diversity, and Control

Anaplasma species, belonging to the family Anaplasmataceae in the order Rickettsiales, are obligate intracellular bacteria responsible for various tick-borne diseases of veterinary and human significance worldwide. With advancements in molecular techniques, seven formal species of Anaplasma and numerous unclassified species have been described. In Africa, several Anaplasma species and strains have been identified in different animals and tick species. This review aims to provide an overview of the current understanding of the molecular epidemiology and genetic diversity of classified and unclassified Anaplasma species detected in animals and ticks across Africa. The review also covers control measures that have been taken to prevent anaplasmosis transmission on the continent. This information is critical when developing anaplasmosis management and control programs in Africa.

Seasonal Investigation of Anaplasma marginale Infection in Pakistani Cattle Reveals Hematological and Biochemical Changes, Multiple Associated Risk Factors and msp5 Gene Conservation

Bovine anaplasmosis is a tick-borne disease caused by an obligate intercellular Gram-negative bacterium named Anaplasma (A.) marginale. In this study, we report the seasonal prevalence, potentially associated risk factors and phylogeny of A. marginale in cattle of three different breeds from Multan District, Southern Punjab, Pakistan. A total of 1020 blood samples (crossbred, n = 340; Holstein Friesian, n = 340; and Sahiwal breed, n = 340) from apparently healthy cattle were collected on a seasonal basis from March 2020 to April 2021. Based on PCR amplification of the msp5 partial sequence, overall, the A. marginale prevalence rate was estimated at 11.1% (113/1020) of the analyzed cattle samples. According to seasons, the highest prevalence rate was observed in autumn (16.5%), followed by winter (10.6%) and summer (9.8%), and the lowest was recorded in the spring (7.5%). The crossbred and Sahiwal cattle were the most susceptible to A. marginale infection, followed by Holstein Friesian cattle (7.9%). Analysis of epidemiological factors revealed that cattle reared on farms where dairy animals have tick loads, dogs coinhabit with cattle and dogs have tick loads have a higher risk of being infected with A. marginale. In addition, it was observed that white blood cell, lymphocyte (%), monocyte (%), hematocrit, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentrations were significantly disturbed in A. marginale-positive cattle compared with non-infested cattle. Genetic analysis of nucleotide sequences and a phylogenetic study based on msp5 partial sequencing demonstrated that this gene appears to be highly conserved among our isolates and those infecting apparently healthy cattle from geographically diverse worldwide regions. The presented data are crucial for estimating the risk of bovine anaplasmosis in order to develop integrated control policies against bovine anaplasmosis and other tick-borne diseases infecting cattle in the country.

Bovine Anaplasmosis: Will there ever be an almighty effective vaccine?

Bovine anaplasmosis is a tick-borne bacterial disease with a worldwide distribution and the cause of severe economic losses in the livestock industry in many countries, including México. In the present work, we first review the elements of the immune response of the bovine, which allows ameliorating the clinical signs while eliminating the majority of the blood forms and generating an immunologic memory such that future confrontations with the pathogen will not end in disease. On the other hand, many vaccine candidates have been evaluated for the control of bovine anaplasmosis yet without no commercial worldwide effective vaccine. Lastly, the diversity of the pathogen and how this diversity has impaired the many efforts to control the disease are reviewed.