Current Clinical Microbiology Reports

, Volume 6, Issue 1, pp 44–50 | Cite as

Toxoplasma: Immunity and Pathogenesis

  • Imtiaz A KhanEmail author
  • Charlotte Ouellette
  • Keer Chen
  • Magali Moretto
Parasitology (N Kumar, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Parasitology


Purpose of Review

Toxoplasmosis is an apicomplexan parasite that can be found in all countries, which causes an infection of the central nervous system. This review outlines some of the recent immunological advances that have been made against this chronic infection that poses a major problem for the immunocompromised individuals.

Recent Findings

Recent studies have demonstrated that in a mouse model of chronic toxoplasmosis, the infection leads to T cell dysfunctionality. The exhaustion that is observed in both CD4 and CD8 T cells is manifested by increased expression of co-inhibitory molecules like PD-1 and leads to reactivation of latent infection. Blockade of PD-1-PDL-1 interaction reverses the exhaustion and prevents reactivation of latent infection in the host.


Prevention of loss of CD4 T cell function can be important therapeutic strategy for controlling chronic toxoplasmosis and preventing reactivation of latent infection.


Toxoplasma CD8 T cells CD4 T cells IL-12 IL-21 Exhaustion 


Funding Information

This work was supported by the NIH grant AI33325 awarded to IAK.

Compliance with Ethics Guidelines

Conflict of Interest

The authors declare that they have no conflict of interest.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors.


Papers of particular interest, published recently, have been highlighted as: • Of importance

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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Imtiaz A Khan
    • 1
    Email author
  • Charlotte Ouellette
    • 1
  • Keer Chen
    • 1
  • Magali Moretto
    • 1
  1. 1.Department of Microbiology, Immunology and Tropical MedicineGeorge Washington UniversityWashingtonUSA

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