The initial immune response during experimental cysticercosis is of the mixed Th1/Th2 type

Abstract

The immunological events that occur during the initial stages of experimental cysticercosis are not known. The studies presented here examined the cytokines produced by peritoneal exudate cells (PECs), splenocytes and mesenteric lymph node (MLN) cells during the first week of infection with larval Taenia crassiceps in BALB/cJ mice. Proliferation assays determined that the earliest time when antigen-specific responses could be measured was 5 days post-infection. Concanavalin A (ConA) stimulation of host cells elicited an initial burst of IL-4 production at 24 h of infection and ConA-stimulated Th2-type cytokine production is predominant by 7 days post-infection. Thus, there are responses at day 1 of infection that seem to promote a Th2-type response. Stimulation of MLN cells, splenocytes and PECs with larval antigens supported previous reports of mixed Th1/Th2-type cytokine production with increases in interleukin (IL)-4, IL-10 and interferon (IFN)-c. Ex vivo IFN-c production by PECs from infected mice was increased at 3, 5 and 7 days postinfection, whereas at these times reduced ex vivo IL-10 production was observed. This ex vivo IFN-c response preceded an increasing IL-10 production by PECs between 3 and 7 days post-infection in parasite-specific and ConA-induced proliferation assays. Thus, infection with larval T. crassiceps results in an initial response mediated by IFN-c that is quickly followed by an increase in IL-10 production and subsequent reduction in the amount of IFN-c being produced.

Alternative Activation of Macrophages: An Immunologic Functional Perspective

“…A positive correlation is found between cytokine secretion and severity of the disease, measured as periportal fibrosis versus intestinal pathology (116). Infection of mice with the cestode Taenia crassiceps induces a mixed Th1/Th2 immune response (117), and unlike the case of infection with the other helminths discussed, caM s play a major role in clearing T. crassiceps infection (118). However, when the infection progresses to a chronic stage, Th2 cytokine dominance results in aaM recruitment that controls excessive inflammatory responses and increased CD4 + apoptosis (119)(120)(121)(122).…”

Identification of Loci Controlling Restriction of Parasite Growth in Experimental Taenia crassiceps Cysticercosis

“…The immunopathology of T. crassiceps cysticercosis in mice is that of an initial non-permissive Th1 type, which shifts to a parasite permissive Th2 type during chronic stage of infection and is accompanied by an increase in IL-4, IL-6 and IL-10 cytokines [38]–[40]. This transition was also reported in individuals with T. solium neurocysticercosis [41] and more precisely, in the brain granulomas surrounding T. solium parasite [42].…”

Similarity and Diversity in Macrophage Activation by Nematodes, Trematodes, and Cestodes

“…Nonetheless, the data is consistent with the general helminth literature in that cestodes by and large have a strong propensity to drive Th2 immune responses. Similar to responses to schistosomes, peritoneal implantation of BALB/c mice with Taenia crassiceps metacestodes results in an initially weak mixed Th1/Th2 response that becomes strongly Th2 dominated as infection progresses to the chronic phase [31, 32]. However, there are resistant mouse strains that expel the parasite in the acute phase due to the dominance of IFN γ production [33].…”