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Published on: March 12, 2015
Macrophage functions in cats experimentally infected with feline immunodeficiency virus and Toxoplasma gondii
1Department of Microbiology, Immunology and Parasitology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853-6401.
Abstract:
It was suspected that feline immunodeficiency virus (FIV) infection would affect the function of feline macrophages, and that the concomitant infection of cats with FIV and Toxoplasma gondii would cause even greater changes in macrophage function. Sixteen specific-pathogen-free kittens, four per group, were infected either with FIV, T. gondii, both pathogens, or neither pathogen. After the cats had been infected with FIV for 14 weeks (8 weeks after T. gondii infection), peritoneal macrophages were collected. Some macrophages were stimulated with lipopolysaccharide and supernatants were collected for the measurement of interleukin-1 production. Other macrophages were infected with T. gondii in a microbiocidal assay. Peritoneal macrophages from cats infected with FIV had decreased interleukin-1 secretion and increased antimicrobial activity. Co-infection with T. gondii apparently had no effect on these modifications of macrophage activity. Thus, acute FIV infection alone caused significant changes in macrophage functions that were not affected by concomitant T. gondii infection.
Insights
Feline immunodeficiency virus (FIV) infection alters macrophage function, reducing interleukin-1 and boosting antimicrobial activity. Toxoplasma gondii co-infection did not further impact these FIV-induced changes in feline macrophages.
Area of Science:
- Veterinary Immunology
- Infectious Diseases
- Feline Health
Background:
- Feline immunodeficiency virus (FIV) is known to affect the immune system in cats.
- The impact of FIV on macrophage function and how co-infection with other pathogens like Toxoplasma gondii might influence this is not fully understood.
Purpose of the Study:
- To investigate the effects of FIV infection on feline macrophage function.
- To determine if co-infection with Toxoplasma gondii exacerbates FIV-induced changes in macrophage activity.
Main Methods:
- Four groups of specific-pathogen-free kittens were infected with FIV, T. gondii, both, or neither.
- Peritoneal macrophages were collected 14 weeks post-FIV infection.
- Macrophage function was assessed via interleukin-1 production after lipopolysaccharide stimulation and a T. gondii microbiocidal assay.
Main Results:
- FIV infection alone led to decreased interleukin-1 secretion by macrophages.
- FIV infection alone resulted in increased antimicrobial activity of macrophages.
- Co-infection with T. gondii did not significantly alter the observed changes in macrophage function caused by FIV.
Conclusions:
- Acute FIV infection significantly modifies feline macrophage function, independent of T. gondii co-infection.
- These findings highlight specific immune dysregulation in FIV-infected cats affecting key innate immune cells.
