Identification of the target molecule of cytotoxic T cells presumably responsible for development of transfusion-associated graft-versus-host disease

Transfusion-associated graft-versus-host disease: an in situ hybridization analysis of the infiltrating donor-derived cells in the cutaneous lesion

BACKGROUND

Acute graft-versus-host disease (GVHD) can occur after a blood transfusion.

OBJECTIVE

In order to elucidate the pathomechanisms responsible for transfusion-associated GVHD, infiltrating donor-derived cells in a cutaneous lesion were analyzed.

METHODS

A skin sample obtained from a 69-year-old woman who developed fatal GVHD after blood transfusions from male donors was studied by performing in situ hybridization (ISH) with a Y-chromosome-specific probe.

RESULTS

The cell infiltrates comprised mainly CD3+ T lymphocytes. Immunohistochemistry and ISH in combination demonstrated that 99% (182/184) of the Y-body-positive cells were CD3+. Y bodies were observed in 80% of the CD8+ cells in the epidermis and dermoepidermal junction and in 77 and 45% of the CD8+ and CD4+ cells, respectively, in the dermis.

CONCLUSION

These findings suggest that both CD4+ and CD8+ cells of donor origin were involved in the development of cutaneous GVHD.

Characterization of T-Cell Clones Derived From Peripheral Blood Lymphocytes of a Patient With Transfusion-Associated Graft-Versus-Host Disease: Fas-Mediated Killing by CD4+ and CD8+ Cytotoxic T-Cell Clones and Tumor Necrosis Factor β Production by CD4+ T-Cell Clones

Transfusion-associated graft-versus-host disease (TA-GVHD) is one of the most serious adverse effects of blood transfusion. It is generally thought to be caused by the infused lymphocytes. Donor-derived cytotoxic T lymphocytes (CTLs) directed against the recipient's HLAs, which have escaped the recipient's immune system and are proliferating, are considered to attack recipient organs and tissues. Despite the seriousness of the disease, the precise mechanism of its development remains unclear and no definitive treatment has been developed. With the aim of developing an effective treatment, we established and characterized T-cell clones from peripheral blood lymphocytes (PBLs) of a TA-GVHD patient. Three types of clones were established. Type I clones were CD8+ and specifically lyse cells that express HLA B52. Type II clones were CD4+, specifically lysed cells that express HLA DR15, and proliferated in response to stimulation with cells that express DR15. Type III clones were also CD4+, showed no cytotoxic activity toward any HLA-expressing cells, and proliferated in response to stimulation with cells that express DR15. Furthermore, we found that the Fas/Fas-ligand (Fas-L) system is involved in the cytotoxicity of the type I and II clones and that the type III clones produce and secrete a large amount of tumor necrosis factor β (TNFβ) after antigen stimulation. Based on our results, these three types of clones can be classified into two categories: those that have the ability to induce GVHD directly by cytolysis and that show no cytotoxic activity and those that have the ability to cause GVHD indirectly through secretion of cytotoxic lymphokines.