Effector CD8 T cell immunity in microsporidial infection: a lone defense mechanism

Abstract

Microsporidia are a group of pathogens, which can pose severe risks to the immunocompromised population such as HIV infected individuals. The expertise to diagnose these pathogens is limited and therefore their prevalence is believed to be much higher than what is currently known. In a mouse model of infections, it has been reported that CD8 T cells are the primary effector cells responsible for protecting the infected host. As the infection is acquired via per-oral route, CD8 T cells in the gut compartment apparently act as a first line of defense against the pathogens. Thus, generation of a robust CD8 T cell response that exhibits polyfunctional ability is critical for host survival. In this review, we describe the effector CD8 T cells generated during microsporidial infection and underline the factors that may be essential for the elicitation of protective immunity against this understudied but significant pathogen. Overall, this review will highlight the necessity for a better understanding of the development of the CD8 T cell response in gut associated lymphoid tissue (GALT) and provide some insights into therapies that may be used to restore defective CD8 T cell functionality in an immunocompromised situation.

UDP-Glucosyltransferases Induced by Nosema bombycis Provide Resistance to Microsporidia in Silkworm (Bombyx mori)

“…Moreover, infection with some microsporidia is a serious threat to human life and health [ 9 , 10 , 11 ]. Although there are many studies on microsporidia, there has not been sufficient research on host response because of the complexity of host–pathogen interactions and the differences among species [ 12 , 13 , 14 ]. The microsporidian N. bombycis was identified from the silkworm, Bombyx mori , in which it causes pebrine and leads to enormous economic losses in the silkworm industry [ 15 ].…”

Intranasal vaccination with an adjuvanted polyphosphazenes nanoparticle-based vaccine formulation stimulates protective immune responses in mice

“…We further analyzed the quality of the stimulated antigen-specific T cell responses by evaluating their capacity to produce more than one cytokine, as it was shown that multifunctional T cells are associated with enhanced protection against certain infections. [30][31][32][33] Immunization via the i.n. route using OVA + c-di-AMP alone or in combination with either of the polyphosphazenes efficiently stimulated multifunctional CD4+ T cells (Figure 4 CD4+ T cells, these formulations performed not only better than the formulations incorporating poly I:C but also better than OVA + c-di-AMP alone (7% bi-and 0% trifunctional; P<0.05) (Figure 4, B).…”

Molecular determination of Enterocytozoon bieneusi in pet shop puppies and breeding kennel dogs

“…It is well demonstrated that the immune response is important to control the opportunistic Microsporidia infections. The immature and suppressive status of immune systems is a risk factor for microsporidiosis [1][2][3][4]18]. Therefore, younger dogs are at high risk due to their immature immune systems [19,20].…”

“…We did not evaluate the sanitary management and environmental condition in each facility. However, the reinfection and/or the reactivation of microsporidiosis according to the concentrated environmental contamination by E. bieneusi spores and the frequent close contact with other dogs in the limited space, which is a stressful situation for animals and can induce the immunosuppressive status, are likely to be major causes of high levels of infection in some facilities [4,17,18,21,22]. The results of the present study suggest that there is no correlation between E. bieneusi infection and fecal condition disorder (soft or diarrhea).…”

“…Despite the fact that the etiology and pathogenicity of Microsporidia have not been clarified, the cases of asymptomatic spore shedding are recognized in dogs and humans, including both immunocompromised and immunocompetent individuals [2,4,9,23]. The immunosuppressed trigger, for example human immunodeficiency virus (HIV) infection, is also indicated to contributes to the symptomatic infections [2,18,24,25].…”