Assessment of the antigenic and neuroprotective activity of the subunit anti-Toxoplasma vaccine in T. gondii experimentally infected mice.

The aim of this study was to evaluate the immunogenic and immunoprotective activities and to determine the neuroprotective capacity of the tetravalent vaccine containing selected recombinant T. gondii antigens (ROP2 + ROP4 + SAG1 + MAG1) administered with safe adjuvants (MPL and alum) using male and female inbred mice. The tested antigenic combination provided partial protection against brain cyst formation, especially in males (reduction in cyst burden by 72%).

Autophagy as a universal intracellular process. A comment on the 2016 Nobel Prize in Physiology or Medicine.

The 2016 Nobel Prize in Physiology or Medicine was awarded to molecular biologist Yoshinori Ohsumi for his work in the field of autophagy (Greek for “self eating”). This fact has once again directed the attention of many scientists to a common cellular phenomenon occurring in all eukaryotes from yeast to mammals, namely the process by which the cell digests and then recycles its components. Although the phenomenon of autophagy was discovered in mammals, a method for monitoring it by light microscopy was established in the unicellular eukaryote, the buddingy east Saccharomyces cerevisiae.

Are poikilothermic animals real hosts for Toxoplasma gondii?

The protozoan Toxoplasma gondii is believed to be a common parasite of almost all endothermic animals and humans. However, recent reports of toxoplasmosis in marine mammals raise concern that cold-blooded animals may also be a potential source of T. gondii infection.

Exosomes in the context of Toxoplasma gondii – host communication.

Extracellular vesicles – EV’s, including exosomes, are known to be essential tools of intercellular communication, enabling the exchange of information without direct contact between cells. Exosomes are secreted both in vitro and in vivo by single- and multi-cellular organisms, regardless of their type, and play an essential role in cell-to-cell communication. EV’s may carry various materials and ongoing studies have provided a new insight into their potential participation in various critical biological processes, including carcinogenesis, protein trafficking, immunostimulation and pathogenesis of infectious diseases.

The role of extracellular vesicles in parasite-host interaction.

Zewnątrzkomórkowe pęcherzyki błonowe (EVs, extracellular vesicles), początkowo uważane za elementy zniszczonych komórek, okazały się niezwykle istotnym sposobem przekazywania informacji między komórkami, bez ich bezpośredniego kontaktu. Ze względu na powszechne występowanie EVs w komórkach organizmów zarówno jedno-, jak i wielokomórkowych należących do różnych grup systematycznych oraz ze względu na pełnioną rolę w komunikacji międzykomórkowej stały się przedmiotem licznych badań i dyskusji. EVs są uwalniane przez komórki prokariotyczne, jak i eukariotyczne, zarówno w warunkach in vivo, jak i in vitro.

Human toxoplasmosis-Searching for novel chemotherapeutics.

The protozoan Toxoplasma gondii, an obligate intracellular parasite, is an etiological agent of human and animal toxoplasmosis. Treatment regimens for T. gondii-infected patients have not essentially changed for years.

Towards vaccine against toxoplasmosis: evaluation of the immunogenic and protective activity of recombinant ROP5 and ROP18 Toxoplasma gondii proteins.

Toxoplasmosis is one of the most common parasitic infections worldwide. An effective vaccine against human and animal toxoplasmosis is still needed to control this parasitosis. The polymorphic rhoptry proteins, ROP5 and ROP18, secreted by Toxoplasma gondii during the invasion of the host cell have been recently considered as promising vaccine antigens, as they appear to be the major determinants of T.

Phytoecdysteroids as modulators of the Toxoplasma gondii growth rate in human and mouse cells.

Background: Searching for new effective drugs against human and animal toxoplasmosis we decided to test the anti-Toxoplasma potential of phytoecdysteroids (α-ecdysone and 20-hydroxyecdysone) characterized by the pleiotropic activity on mammalian organisms including the enhancement of host's anti-parasitic defence. This objective was accomplished by the in vitro evaluation of T. gondii growth in phytoecdysteroid-treated immunocompetent cells of selected hosts: humans and two strains of inbred mice with genetically determined different susceptibility to toxoplasmosis.

Human toxoplasmosis: a comparative evaluation of the diagnostic potential of recombinant Toxoplasma gondii ROP5 and ROP18 antigens.

Toxoplasmosis is one of the most common parasitic diseases worldwide and it poses a serious challenge regarding prevention, diagnosis and therapy. The commonly used diagnostic methods are mostly based on the detection of specific antibodies in sera. Since they are not always accurate enough and do not allow precise definition of the phase of the Toxoplasma gondii infection, there is an urgent need to find specific molecular markers of acute or chronic infection stages.

Recombinant MAG1 Protein of Toxoplasma gondii as a Diagnostic Antigen.

The aim of this study was to evaluate the potential diagnostic usefulness of the full-length recombinant Toxoplasma gondii MAG1 protein by determining the levels of specific IgM and IgG antibodies in mouse and human sera obtained from individuals with acute and chronic toxoplasmosis. The obtained results revealed that IgG antibodies against MAG1 are a sensitive and specific marker of T. gondii infection since the protein was recognized by both mouse and human sera, 100% and 94.

Toxoplasma gondii and mast cells.

Mast cells, discovered by Paul Burnet over one century ago, have been long recognized only as inductors of IgE-dependent allergic diseases (allergy of type I, Th2 lymphocytes dependent). However, numerous recent studies have indicated that they play an essential role in many other immunological and non-immunological processes. Infection with Toxoplasma gondii elicits the induction of a strong cell-mediated immunity characterized by a highly-polarized Th1 response, which can protect against allergy.

Toxoplasma gondii: cloning, expression and immunoreactivity of recombinant ROP5 and ROP18 antigens.

Early diagnosis and determining the infective stage are critical for effective therapy of toxoplasmosis. Owing to the progress in biotechnology, commonly used native, non-standardized diagnostic antigens should be replaced by genetically engineered antigens. The recombinant proteins are also promising components of subunit vaccines against Toxoplasma gondii infections.

Toxoplasma gondii and the host cells.

The protozoan Toxoplasma gondii, described by Nicolle and Manceaux in 1908, is a ubiquitous and cosmopolitan parasite that infects a wide range of mammal and bird species with high prevalence. The biological success of T. gondii is associated with the formation of a specific relationship between the parasite and host cells leading to the establishment of a latent, chronic infection.

Veterinary vaccines against toxoplasmosis.

Toxoplasma gondii is a cosmopolitan protozoan parasite that infects a wide range of mammal and bird species. Common infection leads to high economic (e.g.

Natural microbiota in viral and helminth infections. Addendum to: Personalized vaccination. II. The role of natural microbiota in a vaccine-induced immunity.

Numerous original and review papers have emerged over recent years concerning the natural microbiota and its interaction with the mammal host's body. This addendum supplements in short our previous review article on the role of microbiota in the host immunity paying, particular attention to such essential aspects as the composition and role of gut microbiota in viral infections as well as the interplay between the microbiota and the macrofauna inhabiting the mammalian gastrointestinal tract. The host immune system, commensal microbiota and macrofauna are elements of an integrated system in which the relationships are bidirectional.

Functional exhaustion of T lymphocytes in chronic toxoplasmosis.

One of the most characteristic features of many intracellular parasite infections is their chronicity indicating that the host immune system is not capable of eradicating the pathogen. Toxoplasma gondii is the most successful parasite worldwide, infecting an extraordinarily broad range of hosts (endothermic animals and humans) and almost all cell types. Recent studies have revealed that in late chronic toxoplasmosis CD8+ T lymphocytes become progressively exhausted and this dysfunction is suggested to be responsible for the reactivation of latent infection, which may result in a life-threatening disease in immunocompromised individuals (e.

Sex-dependent neurotransmitter level changes in brains of Toxoplasma gondii infected mice.

The protozoan parasite Toxoplasma gondii has the ability to alter intermediate host behavior, most impressively the natural aversion to cat scent, to favor the predation by the definitive host. However, the underlying mechanism of the observed phenomenon still remains unknown. Since changes in the neurotransmitter level are postulated as a possible contributing factor, the aim of this work was to assess the monoamine systems activity in specified brain regions involved in the natural defense behaviors, emotion evaluation, and motor and sensory stimuli integration in experimentally T.

Mucosal vaccination--an old but still vital strategy.

The basic premise of vaccinology is to achieve strong protective immunity against defined infectious agents by a vaccine mimicking the effects of natural primary exposure to a pathogen. Because an exposure of humans and animals to microbes occurs mostly through mucosal surfaces, targeting the mucosa seems a rational and efficient vaccination strategy. Many experimental and clinical data confirmed that mucosal immunization offers many advantages over widely used in human and veterinary medicine subcutaneous or intramuscular immunization.

Toxoplasma gondii: the vaccine potential of three trivalent antigen-cocktails composed of recombinant ROP2, ROP4, GRA4 and SAG1 proteins against chronic toxoplasmosis in BALB/c mice.

Toxoplasmosis is one of the world's most widespread zoonoses caused by protozoan parasite Toxoplasma gondii. The development of an effective vaccine for controlling toxoplasmosis is an extremely important issue due to the serious clinical and veterinary outcomes of this parasitosis. The objective of this study was evaluation of vaccine potential of three trivalent subunit recombinant vaccines composed of rROP2+rGRA4+rSAG1, rROP2+rROP4+rGRA4 and rROP2+rROP4+rSAG1 against chronic toxoplasmosis in BALB/c (H-2(d)) mice.

Behavioral changes in mice caused by Toxoplasma gondii invasion of brain.

Toxoplasma gondii, a protozoan parasite, is capable of infecting a broad range of intermediate warm-blooded hosts including humans. The parasite undergoes sexual reproduction resulting in genetic variability only in the intestine of the definitive host (a member of the cat family). The parasite seems to be capable of altering the natural behavior of the host to favor its transmission in the environment.

Toxoplasma gondii--an amazing parasite. A comment to the article of Koshy A.A. et al. "Toxoplasma co-opts host cells it does not invade".

Ubiquitous parasite of humans and endothermic animals Toxoplasma gondii (type Apicomplexa), identified by Nicolle and Manceaux over 100 years ago, is still an object of numerous extensive studies bringing very interesting and often even surprising observations as that announced in the title [1].

Personalized vaccination? II. The role of natural microbiota in a vaccine-induced immunity.

Inter-individual variation in immune response to widely used prophylactic vaccines against infectious diseases is strongly influenced by sex, MHC (Major Histocompatibility Complex), age and current hormones status of vaccinated individuals. Numerous findings showed that microorganisms residing at different sites of human or animal body (natural microbiota), especially in the gastrointestinal tract, appear to contribute to nearly every element of the host's physiology. Recently, the microbiota is also supposed to be an underappreciated yet, but very important factor responsible for diverse vaccine efficacy observed in humans from developing vs.

Evaluation of three recombinant multi-antigenic vaccines composed of surface and secretory antigens of Toxoplasma gondii in murine models of experimental toxoplasmosis.

The great clinical and economical impact of Toxoplasma gondii infections makes the development of an effective vaccine for controlling toxoplasmosis an extremely important aim. In the presented study, we evaluate the protective and immunogenic properties of three recombinant subunit vaccines composed of rROP2+rGRA4+rSAG1, rROP2+rROP4+rGRA4 and rROP2+rROP4+rSAG1 proteins of T. gondii in an experimental toxoplasmosis model in the C3H/HeJ and C57BL/6 mouse strains.

Determination of diagnostic value of Toxoplasma gondii recombinant ROP2 and ROP4 antigens in mouse experimental model.

The aim of this study was to test the potential diagnostic usefulness of recombinant Toxoplasma gondii rhoptry antigens, ROP2 and ROP4, with respect to toxoplasmosis detection and infection phase distinction in laboratory mouce by determining specific serum IgM and IgG antibodies with the use of indirect ELISA technique. The mice antibody response to ROP antigens was significantly higher in the IgM than in the IgG class with the peak on the turn of acute and latent infection, whereas the response to recombinant SAG1 antigen, used as control, revealed preferential synthesis of IgG antibodies with the highest absorbance values measured during latent toxoplasmosis.