What Is the Role of PGK1 in Immuno-Related Pancytopenia?

A study published in Hematology has evaluated the role of phosphoglycerate kinase 1 (PGK1) autoantibodies in the diagnosis of immuno-related pancytopenia (IRP).

The study included 59 patients with untreated IRP (median age, 39 years), 62 patients recovered from IRP, and 15 patients with severe aplastic anemia (SAA) in case-control groups. Patients with IRP received corticosteroids (prednisone 0.5 mg/kg/day), stimulating hematopoietic therapy, and high-dose intravenous immunoglobulin.

The researchers utilized enzyme-linked immunosorbent assay (ELISA) to detect anti-PGK1 antibodies, as well as flow cytometry (FCM) to detect CD5 + B cells and autoantibodies on bone marrow mononuclear cells (BMMNC-Ab). The positivity rate of autoantibodies tested by FCM was defined as greater than 4%.

When comparing rates of CD34+ IgG/IgM positivity, CD235a + IgG/IgM positivity, CD15+ IgG/IgM positivity, and BMMNC-Ab IgG/IgM positivity between the untreated IRP group and the recovered IRP group, the percentage of CD34+ IgM-positive patients decreased significantly in the recovery group (23.53% vs 6.67%; P=0.0149). The difference with the untreated IRP group was statistically significant (P<0.05), while the differences in other groups were not.

The serum level of anti-PGK1 antibodies of patients with untreated IRP (0.99 ± 0.23) was “significantly higher” than that of patients with SAA (0.56 ± 0.30; P<0.0001). However, the levels of anti-PGK1 antibodies were not significantly different between the untreated IRP group and the recovered IRP group (0.98 ± 0.25; P>0.05).

Patients with IRP were divided into two groups: platelets greater than 50 × 10⁹/L and platelets less than 50 × 10⁹/L. Among those with recovered IRP, the percentage of patients with positive PGK1-antibodies was lower in the platelets greater than 50 × 10⁹/L group (15% vs 16%). In addition, PGK1 antibody levels in patients with recovered IRP were positively correlated with white blood cell and circulating immune complexes levels and negatively correlated with platelet levels.

Hemoglobin, platelets, neutrophils, and percent reticulocytes were significantly higher in patients with recovered IRP compared with untreated IRP after treatment (P<0.05), and the levels of C3 and C4 increased after treatment. The C3 and C4 levels were 92.84 ± 3.319 mg/dL and 19.47 ± 0.9393 mg/dL in the untreated IRP group, respectively, compared with 112.6 ± 3.702 mg/dL and 23.10 ± 0.8457 mg/dL in the recovered IRP group.

“Detecting anti-PGK1 antibodies might have some clinical value in differentiating IRP from SAA,” the authors concluded. “The tests of CD34+ IgM positivity, CD5+ B cells, and C3 and C4 levels are of clinical value in assessing the curative effect of IRP patients.”

Reference

Hao S, Zhang Y, Xiao N, et al. Anti-PGK1 antibodies in immuno-related pancytopenia. Hematology. 2025;30(1):2468565. doi:10.1080/16078454.2025.2468565