Elevated T. gondii IgG antibodies in relationship to affective, cognitive and behavioural dysregulation
The higher antibody titre categories could be an effect of the virulence and spread of infection, or the tendency to reactivate more often. This may also occur with a more recent infection, or a reinfection with a different strain (se- rial measurements of IgG and IgM antibodies would be important for this purpose). Certain phenotypes, such as changes in novelty thinking and intelligence, are stronger related to more recent infections (Flegr et al. 2003), sug- gesting a transient effect. Other phenotypes, however, are related to the duration of exposure, thus with older infections (Flegr et al. 1996, 2000). As in many individuals’ ti- tres tend to diminish in time, certain effects that need time may be associated with lower titres, and even subthreshold titres. Another potential mechanism involves cross-reactivity with other infections and autoimmune disease with innate and acquired molecular mimicry, where the antibodies themselves might directly affect neural tissue. For a more in-depth discussion of this topic, the reader is directed to the Discussion section our article in the same issue of Folia Parasitologica (Postolache et al. 2025).
Publication Date: 2025-09-05