Enhancement by Recombinant Human Interleukin 2 of Host Resistance to Toxoplasma gondii Infection in Pregnant Mice

• Published in: MICROBIOLOGY and IMMUNOLOGY 1993, Vol.37(7), pp.583-590
• Main Authors: Shirahata, Toshikazu, Muroya, Naoyoshi, Ohta, Chikako, Goto, Hitoshi, Nakane, Akio
• Format: Article
• Language: English
• Subjects: Acute Disease; Animals; Biological and medical sciences; Experimental protozoal diseases and models; Female; Immunity, Innate; Infectious diseases; Interferon-gamma; Interferon-gamma - biosynthesis; Interferon-gamma - therapeutic use; Interleukin 2; Interleukin-2 - biosynthesis; Interleukin-2 - therapeutic use; Medical sciences; Mice; Mice, Inbred ICR; Parasitic diseases; Pregnancy; Pregnancy Complications, Parasitic - drug therapy; Pregnancy, Animal; Pregnant mice; Protozoal diseases; Recombinant Proteins - therapeutic use; Spleen - metabolism; Toxoplasma - pathogenicity; Toxoplasma gondii; Toxoplasmosis, Animal - drug therapy; Toxoplasmosis, Animal - mortality
• ISSN: 0385-5600; 1348-0421
• DOI: 10.1111/j.1348-0421.1993.tb01680.x

The lymphokine production by pregnant mice infected with a lethal dose of Toxoplasma gondii was evaluated in comparison with that by virgin mice infected with a sublethal dose of this protozoan parasite. Splenocytes taken from mice before and on the day after infection produced considerable amounts of IL-2 in response to concanavalin A (Con A) stimulation, but the titers rapidly declined in both pregnant and virgin mice as infection progressed. A trace amount or undetectable level of IL-2 was produced by splenocytes from acutely infected mice when stimulated with Toxoplasma lysate antigen (TLA). In contrast to the kinetics of IL-2 production, the levels of IFN-γ produced by splenocytes cultured with Con A or TLA increased steadily in the later stage of infection in both pregnant and virgin mice. Thus, the response to Con A or TLA of splenocytes to produce IL-2 and IFN-γ differed strikingly in acute toxoplasmosis in mice. The administration of rHuIL-2 resulted in a significant decrease in the mortality of pregnant mice infected with a lethal dose of Toxoplasma. The combination of rHuIL-2 and rMuIFN-γ increased the survival rate slightly but not significantly compared with pregnant mice receiving either rHuIL-2 or rMuIFN-γ. Moreover, exogenously administered rHuIL-2 enhanced the production of both IFN-α and IFN-γ in the bloodstreams of pregnant mice, in accordance with the decreased mortality. These results indicate that IL-2 may play a significant role in modulating the host defense against Toxoplasma infection in pregnant mice.