Jean Lu has completed her PhD from North Carolina State University and postdoctoral studies from Duke University in USA. She is a professor and a researcher in the Department of Molecular and Cellular Biology at Kennesaw State University. She has published more than 20 papers in reputed journals and has been serving as an editorial board member of repute.
Salmonella is one of the most common foodborne bacterial pathogens throughout the world. In the United States, Salmonella causes over one million foodborne illnesses and billions of dollar loss to the society yearly. Salmonella enterica serovar Thompson is one of the common serovars causing Salmonellosis. Effective control of S. Thompson as well as other Salmonella serivars is essential to public health. Using bacteriophages (phages) to control foodborne bacterial pathogens, especially those antibiotic resistant Salmonella, is a promising novel biocontrol method. The objectives of this study were to isolate and to characterize the isolated phage infecting Salmonella enterica Thompson. A phage (designated as ΦEnt) infecting S. Thompson was isolated from turkey. The phage forms medium-size clear plaques on its host bacterial lawn. Transmission electron microscopy revealed that ΦEnt belongs to Siphoviridae family. One-step growth kinetics study (at a multiplicity of infection of 0.02) showed that the latent period of ΦEnt was about 40 min (including 10 min for adsorption), the rise period was 30 min, and the average burst size was 32 phage particles per infected cell. Host range study showed that the phage was also able to infect a few other Salmonella serovars including S. Infantis. Protein analysis revealed that the phage has several structural proteins in the range from 30 to 70 KDa. The phage infection in a model food system resulted in rapid cell lysis. These results indicated that ΦEnt has a high potential for use as a biocontrol agent against Salmonella in food systems.
Adriano Pereira is a teacher in the areas of health and biological sciences at São Camilo University, São Paulo, Brazil. He is a Master degree in Veterinary Medicine and PhD student in Environmental and Experimental Pathology. His research involves studying microsporidia with a focus on biology and immune response against this emerging and opportunistic pathogen
Microsporidia are unicellular organisms that infect a wide range of vertebrate and invertebrate species. Encephalitozoon cuniculi is one of the most common microsporidian species in human. These pathogens were considered protozoa but recently have been reclassified phylogenetically as fungi. Our knowledge about the immunity during microsporidiosis is not fully understood and we decided to study in vitro the role of B-1 cells and cytokines involved in the immune response against E. cuniculi infection. Supernatants from cultures of Adherent Peritoneal Cells (APerC) from BALB/c mice and APerC from XID mice (B-1 cells deficient) infected and not with E. cuniculi after 30 min, 1h, 48h, 96h and 144h was collected and cytokines were measured. In the supernatants of APerC from BALB/c mice there were levels of MCP-1 and TNF detected and they decreased after 48 hours in both groups (uninfected and infected with E. cuniculi). Besides that, increased levels of IL-6 were observed in infected group in 96 and 144 hours and IL-10 in 144 hours. In supernatants of APerC from XID there were low levels of MCP-1 and TNF in both groups and levels of TNF decreased after 96 hours and MPC-1 were not found after this time. There was an increased in levels of IL-10 in the infected group with 30 minutes and 1 hour. The cytokine IL-12 was tested but detectable levels were not found. These preliminary results of our research can help to better understand the role of B-1 cell and cytokines envolved in the pathogenesis of E.cuniculi infection.