The immunologic abnormalities in patients with paroxysmal nocturnal hemoglobinuria are associated with disease progression

Abstract

Objectives: To suggest the presence of a hyperimmune state in patients, and indicate that immune system attack on glycosylphosphatidylinositol (+) (GPI⁺) cells while escaping GPI^- cell immunity.

Methods: We retrospective the immune cell subtypes in peripheral blood from 25 patients visiting Tianjin Medical University General Hospital, Tianjin, China, with classical paroxysmal nocturnal hemoglobinuria (PNH) and 50 healthy controls.

Results: The total CD3⁺ and CD3⁺CD8⁺ cell levels were higher in patients with PNH. The CD3⁺ cells are positively, correlated with lactate dehydrogenase (LDH; r=0.5453, p=0.0040), indirect bilirubin (r=0.4260, p=0.0379) and Flear^- cells in monocytes (r=0.4099, p=0.0303). However, a negative correlation was observed between CD3⁺ cells and hemoglobin (r= -0.4530, p=0.0105). The total CD19⁺ cells decreased in patients, and CD19⁺ cells were negatively correlated with LDH (r= -0.5640, p=0.0077) and Flear^- cells in monocytes (r= -0.4432, p=0.0341). Patients showed an increased proportion of total dendritic cells (DCs), with a higher proportion of myeloid DCs (mDCs) within the DC population. Moreover, the proportion of mDC/DC was positively correlated with CD59^- cells (II + III types) in red cells (r=0.7941, p=0.0004), Flear^- cells in granulocytes (r=0.5357, p=0.0396), and monocytes (r=0.6445, p=0.0095).

Conclusion: Our results demonstrated that immune abnormalities are associated with PNH development.

Keywords: B-cells; T-cells; cytokines; dendritic cells; paroxysmal nocturnal hemoglobinuria.

Figure 1

- Differences in T-cells and their subsets between patients with PNH and healthy controls. A) In comparison to healthy controls, the proportion of total T-cells (CD3⁺) increased considerably. B) We found that patients with PNH had higher percentages of CD3⁺CD8⁺ and CD8⁺CD4⁺ cells, which is consistent with the T-cell results. CD4⁺/CD8⁺ ratio was decreased in patients with PNH. C) In both groups, in the proportion of CD3⁺CD4⁺ cells were the same. D-G) Positive correlations were found between the number of CD3+ cells in patients with PNH and LDH, indirect bilirubin levels, and Flear− cells in monocytes; on the other hand, negative correlations were seen with hemoglobin levels.

Figure 2

- Differences in B-cells and their subsets between patients with PNH and healthy controls. A) Patients with PNH had a lower proportion of total B-cells. B) The proportion of naive B-cells were decreased. The percentage of CD21^low B-cells, Class-unswitched memory B-cells and Class-switched memory B-cells increased significantly. C) The percentages of Marginal zone B-cells, Breg-cells and Transitional B-cell were not different between the 2 groups. D&E) The proportion of CD19⁺ cells is negatively correlated with LDH level and the ratio of Flear⁻ cells in monocytes.

Figure 3

- Differences in DC cells and their subsets between patients with PNH and healthy controls. A) When comparing patients to healthy controls, there was an increase in the proportion of total DC cells. B) The percentage of pDC/DC% was lower while mDC/DC% was higher than normal controls. There was also a marked decrease in the pDC/mDC and mDC1/mDC ratio. C) The ratio of mDC2/mDC and CD16⁺mDC/mDC did not have distinction between patients and controls. D) The proportion of mDC/DC cell was positively correlated with CD59⁻ cells (II + III types) in red cells and Flear− cells in granulocytes and monocytes.

Figure 4

- Differences in several cytokines and their subsets between patients with PNH and healthy controls. A) The plasma concentration of IL-6 increased and IL-17A are decreased in PNH, compared with healthy controls. B) Hemoglobin levels and IL-17A plasma concentration are correlated.