The pathophysiology of ITP stems from complex immune dysregulation drives thrombocytopenia and inflammation

The pathophysiology of ITP stems from complex immune dysregulation leading to two primary mechanisms*

The underlying cause of ITP is complex immune dysregulation that involves multiple components of the innate and adaptive immune system driving autoimmunity and systemic inflammation^1,3,4

The pathophysiology of ITP stems from complex immune dysregulation drives thrombocytopenia and inflammation.^1,2,5-12

In healthy individuals, the regulatory interplay between innate and adaptive immunity allows for immune homeostasis.^8,9,14

Tregs play a crucial role in maintaining immune tolerance by suppressing aberrant immune responses.⁸

Th cells in the spleen activate B cells and macrophages, key players of immune response.²

Macrophages, primarily in the spleen, recognize and phagocytize autoantibody-opsonized platelets, leading to their rapid destruction.^2,10

This process activates macrophages to present platelet antigens and release pro-inflammatory cytokines, driving the inflammatory response in ITP

Regulation of immune response is impaired due to:

Dysregulation of T cells leading to imbalance of proinflammatory factors¹⁰
NLRP3 inflammasome activation driven
Leading to a chronic pro-inflammatory state that further drives T-cell and B-cell dysfunction, contributes to platelet destruction, and amplifies the overall immune response in ITP.¹⁰

HSC, hematopoietic stem cell; IL, interleukin; ITP, immune thrombocytopenia; NLRP3, nucleotide-binding domain leucine-rich repeat containing protein 3; PLT, platelet; Tc cell, cytotoxic T cell; Th cell, T helper cell; Treg, regulatory T cell.

*The fundamental etiology of ITP may arise from an environmental trigger occurring in a genetically predisposed patient, as well as potential expansion of innate lymphoid cells, but a definitive cause remains elusive.⁵