Immunoproteomics and Surfaceomics of the Adult Tapeworm Hymenolepis diminuta.

In cestodiasis, mechanical and molecular contact between the parasite and the host activates the immune response of the host and may result in inflammatory processes, leading to ulceration and intestinal dysfunctions. The aim of the present study was to identify antigenic proteins of the adult cestode Hymenolepis diminuta by subjecting the total protein extracts from adult tapeworms to 2DE immunoblotting (two-dimensional electrophoresis combined with immunoblotting) using sera collected from experimentally infected rats. A total of 36 protein spots cross-reacting with the rat sera were identified using LC-MS/MS. As a result, 68 proteins, including certain structural muscle proteins (actin, myosin, and paramyosin) and moonlighters (heat shock proteins, kinases, phosphatases, and glycolytic enzymes) were identified; most of these were predicted to possess binding and/or catalytic activity required in various metabolic and cellular processes, and reported here as potential antigens of the adult cestode for the first time. As several of these antigens can also be found at the cell surface, the surface-associated proteins were extracted and subjected to in-solution digestion for LC-MS/MS identification (surfaceomics). As a result, a total of 76 proteins were identified, from which 31 proteins, based on 2DE immunoblotting, were predicted to be immunogenic. These included structural proteins actin, myosin and tubulin as well as certain moonlighting proteins (heat-shock chaperones) while enzymes with diverse catalytic activities were found as the most dominating group of proteins. In conclusion, the present study shed new light into the complexity of the enteric cestodiasis by showing that the H. diminuta somatic proteins exposed to the host possess immunomodulatory functions, and that the immune response of the host could be stimulated by diverse mechanisms, involving also those triggering protein export via yet unknown pathways.

Identification of immunogenic proteins of the cysticercoid of Hymenolepis diminuta.

BACKGROUND: A wide range of molecules are used by tapeworm metacestodes to establish successful infection in the hostile environment of the host. Reports indicating the proteins in the cestode-host interactions are limited predominantly to taeniids, with no previous data available for non-taeniid species. A non-taeniid, Hymenolepis diminuta, represents one of the most important model species in cestode biology and exhibits an exceptional developmental plasticity in its life-cycle, which involves two phylogenetically distant hosts, arthropod and vertebrate. RESULTS: We identified H. diminuta cysticercoid proteins that were recognized by sera of H. diminuta-infected rats using two-dimensional gel electrophoresis (2DE), 2D-immunoblotting, and LC-MS/MS mass spectrometry. Proteomic analysis of 42 antigenic spots revealed 70 proteins. The largest number belonged to structural proteins and to the heat-shock protein (HSP) family. These results show a number of the antigenic proteins of the cysticercoid stage, which were present already in the insect host prior to contact with the mammal host. These are the first parasite antigens that the mammal host encounters after the infection, therefore they may represent some of the molecules important in host-parasite interactions at the early stage of infection. CONCLUSIONS: These results could help in understanding how H. diminuta and other cestodes adapt to their diverse and complex parasitic life-cycles and show universal molecules used among diverse groups of cestodes to escape the host response to infection.

Comparative Proteomic Analysis of Hymenolepis diminuta Cysticercoid and Adult Stages.

Cestodiases are common parasitic diseases of animals and humans. As cestodes have complex lifecycles, hexacanth larvae, metacestodes (including cysticercoids), and adults produce proteins allowing them to establish invasion and to survive in the hostile environment of the host. Hymenolepis diminuta is the most commonly used model cestode in experimental parasitology. The aims of the present study were to perform a comparative proteomic analysis of two consecutive developmental stages of H. diminuta (cysticercoid and adult) and to distinguish proteins which might be characteristic for each of the stages from those shared by both stages. Somatic proteins of H. diminuta were isolated from 6-week-old cysticercoids and adult tapeworms. Cysticercoids were obtained from experimentally infected beetles, Tenebrio molitor, whereas adult worms were collected from experimentally infected rats. Proteins were separated by GeLC-MS/MS (one dimensional gel electrophoresis coupled with liquid chromatography and tandem mass spectrometry). Additionally protein samples were digested in-liquid and identified by LC-MS/MS. The identified proteins were classified according to molecular function, cellular components and biological processes. Our study showed a number of differences and similarities in the protein profiles of cysticercoids and adults; 233 cysticercoid and 182 adult proteins were identified. From these proteins, 131 were present only in the cysticercoid and 80 only in the adult stage samples. Both developmental stages shared 102 proteins; among which six represented immunomodulators and one is a potential drug target. In-liquid digestion and LC-MS/MS complemented and confirmed some of the GeLC-MS/MS identifications. Possible roles and functions of proteins identified with both proteomic approaches are discussed.

The structural and functional changes of blood cells and molecular components in diabetes mellitus.

It is known fact that diabetes mellitus (DM) affects blood cells. Changes in the erythrocyte membrane, disorder in hemoglobin oxygen-binding and modification in mechanical characteristics, are effects of hyperglycemia on red blood cells. Altered susceptibility infection of patients with diabetes has been ascribed to a depression in the function of polymorphonuclear leukocytes. Neutrophil function in patients with diabetes with good glucose control is slightly different than in healthy ones. DM causes significant changes in lymphocytes metabolism and their functions. Patients with diabetes, presenting with acute coronary syndrome, are at higher risk of cardiovascular complications and recurrent ischemic events in comparison to non-diabetic counterparts. Various mechanisms, including endothelial dysfunction, platelet hyperactivity, and abnormalities in coagulation and fibrynolysis have been implicated for this increased atherothrombotic risk. There are many other alterations of blood cells due to DM. In the present review we focused on modifications of blood cells due to DM. Then, as a second point, we explored how the changes affect functions of red blood cells, white blood cells and platelets.

Mass spectrometry analysis of the excretory-secretory (E-S) products of the model cestode Hymenolepis diminut a reveals their immunogenic properties and the presence of new E-S proteins in cestodes.

Hymenolepis diminuta is an important model species in studies of therapeutics, biochemical processes, immune responses and other aspects of cestodiasis. The parasite produces numerous excretory-secretory (E-S) proteins and a glycocalyx covering its body. Our study focused on the mass spectrometry analysis of the E-S material with an objective to determine if E-S contains any new proteins, in particular those that can be identified as: antigens, vaccine candidates and drug targets. These proteins might engage directly in host-parasite interactions. Adult parasites collected from experimentally infected rats were cultured in vitro for 5 and 18h. Immunoblotting was used to verify which E-S protein bands separated in SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) react with specific antibodies from sera of infected rats. We identified thirty-nine proteins by LC-MS/MS (liquid chromatography mass spectrometry). Results indicated the presence of proteins that have never been identified in cestode E-S material. Immunoblotting showed the immunogenicity of E-S products of H. diminuta, most probably associated with the presence of proteins known as antigens in other flatworm species. Among identified proteins are those engaged in immunomodulatory processes (eg. HSP), in response to oxidative stress (peroxidasin) or metabolism (eg. GAPDH). The predominant functions are associated with metabolism and catalytic activity. This is the first study identifying E-S-proteins in adult tapeworms, thus providing information for better understanding host-parasite interrelationships, and may point out potential targets for vaccines or drug discovery studies, as among the proteins observed in our study are those known to be antigens.