lactoferrin and Toxoplasmosis--Animal

This study evaluated the immune-potentiating effect of administrating bovine Lactoferrin (LF) to immunocompetent (IC) and immunosuppressed (IS) mice prior to infection with tachyzoites of T. gondii RH strain. Mice were IS with cyclophosphamide. LF was given in seven of them as oral doses on alternate days. Immunological and parasitological assessments showed that LF induced statistical significance comparable resistance against acute toxoplasmosis in IC and IS mice. This was verified by elevated splenic CD4+ T lymphocytes, reduced tachyzoites' viability and infectivity, with diminished parasite burdens. So, mice mortality declined and their survival was prolonged. This indicated that LF have prophylactic efficacy against human toxoplasmosis in risky persons with alleviating immune balance.

Topics: Animals; Cattle; CD4-Positive T-Lymphocytes; Cyclophosphamide; Immunocompromised Host; Immunosuppressive Agents; Lactoferrin; Lymphocyte Activation; Mice; Toxoplasmosis, Animal

The protective effect of lactoferricin against Toxoplasma gondii infection was examined in experimental murine toxoplasmosis. All mice orally administered 5.0 mg of lactoferricin, and challenged with cysts of T. gondii at a dose of LD90 survived until the end of experiment (35 days post challenge). Intraperitoneal administration of 0.1 mg of lactoferricin also prevented death in 100% of treated mice challenged with T. gondii cysts. In contrast, 80% of untreated mice died of acute toxoplasmosis within 14 days post challenge. In the mice treated perorally with lactoferricin, the number of cysts in the brain was significantly lower than that in untreated mice. Levels of interferon-r in the serum of infected mice treated perorally with lactoferricin showed a tendency to lower than those in the infected mice without treatment. These results demonstrate that oral administration of lactoferricin induces resistance to T. gondii infection in mice.

Topics: Administration, Oral; Animals; Antiprotozoal Agents; Brain; Injections, Intraperitoneal; Lactoferrin; Lethal Dose 50; Mice; Survival Rate; Toxoplasma; Toxoplasmosis, Animal

Murine antibody responses to soluble proteins are generally restricted to the immunoglobulin G1 (IgG1) isotype. When mice were infected with Toxoplasma gondii Beverley and concomitantly immunized with a soluble unrelated protein antigen, a modification in the isotypic distribution of antibodies directed against this nonparasite antigen was observed, with a preferential production of IgG2a. Interestingly, when mice were immunized with a soluble protein antigen during the chronic phase (day 40) of infection with T. gondii Beverley, a similar modification in the isotypic distribution of antiprotein antibodies was observed.

Topics: Acute Disease; Animals; Antibodies, Protozoan; Chronic Disease; Cytokines; Female; Immunoglobulin Isotypes; Interleukin-12; Lactoferrin; Mice; Mice, Inbred BALB C; RNA, Messenger; Spleen; Toxoplasmosis, Animal