Evaluation of in vitro Activation of Bovine Endometrial and Vaginal Epithelial and Blood Mononuclear Cells to Produce Nitric Oxide in Response to Mycoplasma bovis, Mycoplasma bovigenitalium and Ureaplasma diversum

Genital mycoplasmosis is a condition present in bovine production systems, and the most important agents involved are Mycoplasma bovis, Mycoplasma bovigenitalium and Ureaplasma diversum. Some aspects of their pathogenesis remain unclear. This study was designed in order to evaluate their ability to stimulate mononuclear cells from the endometrium, vagina and peripheral blood of cycling and healthy cows to produce nitric oxide (NO). Cellular cultures of endometrial, vaginal and peripheral blood cells from 33 healthy cows were cultivated with Mycoplasma bovis, Mycoplasma bovigenitalium and Ureaplasma diversum originated from the 4th passage in culture broth and the NO production was measured by the Greiss reaction. Confirmation of the presence of mononuclear cells and of the agents during and after the NO assay was done by Giemsa stained smears and further cultivation and detection by PCR reaction. Mononuclear cells from all samples produced NO. Mycoplasma bovigenitalium stimulated higher NO production than the others (p<0.05). Endometrial cells produced less NO than vaginal or blood cultured cells. In conclusion, it seems that Mycoplasma bovis, Mycoplasma bovigenitalium, and Ureaplasma diversum are able to activate mononuclear cells and induce the production of NO, thus suggesting that this pathway is elicited in response to the primary infection by these agents. More studies are necessary to verify why these agents remain in the bovine reproductive tract for long periods and how they reassume deleterious effects.

A Review of Ureaplasma diversum: A Representative of the Mollicute Class Associated With Reproductive and Respiratory Disorders in Cattle

The Mollicutes class encompasses wall-less microbes with a reduced genome. They may infect plants, insects, humans, and animals including those on farms and in livestock. Ureaplasma diversum is a mollicute associated with decreased reproduction mainly in the conception rate in cattle, as well as weight loss and decreased quality in milk production. Therefore, U. diversum infection contributes to important economic losses, mainly in large cattle-producing countries such as the United States, China, Brazil, and India. The characteristics of Mollicutes, virulence, and pathogenic variations make it difficult to control their infections. Genomic analysis, prevalence studies, and immunomodulation assays help better understand the pathogenesis of bovine ureaplasma. Here we present the main features of transmission, virulence, immune response, and pathogenesis of U. diversum in bovines.

Immunoinformatics and analysis of antigen distribution of Ureaplasma diversum strains isolated from different Brazilian states

Background Ureaplasma diversum has numerous virulence factors that contribute to pathogenesis in cattle, including Lipid-associated membrane proteins (LAMPs). Therefore, the objectives of this study were to evaluate in silico important characteristics for immunobiological applications and for heterologous expression of 36 LAMPs of U. diversum (UdLAMPs) and, also, to verify by conventional PCR the distribution of these antigens in strains of Brazilian states (Bahia, Minas Gerais, São Paulo, and Mato Grosso do Sul). The Manatee database was used to obtain the gene and peptide sequences of the antigens. Similarity and identity studies were performed using BLASTp and direct antigenicity was evaluated by the VaxiJen v2.0 server. Epitope prediction for B lymphocytes was performed on the BepiPred v2.0 and CBTOPE v1.0 servers. NetBoLApan v1.0 was used to predict CD8+ T lymphocyte epitopes. Subcellular location and presence of transmembrane regions were verified by the software PSORTb v3.0.2 and TMHMM v2.2 respectively. SignalP v5.0, SecretomeP v2.0, and DOLOP servers were used to predict the extracellular excretion signal. Physico-chemical properties were evaluated by the web-software ProtParam, Solpro, and Protein-sol. Results In silico analysis revealed that many UdLAMPs have desirable properties for immunobiological applications and heterologous expression. The proteins gudiv_61, gudiv_103, gudiv_517, and gudiv_681 were most promising. Strains from the 4 states were PCR positive for antigens predicted with immunogenic and/or with good characteristics for expression in a heterologous system. Conclusion These works contribute to a better understanding of the immunobiological properties of the UdLAMPs and provide a profile of the distribution of these antigens in different Brazilian states.