Should we use Extracorporeal Photopheresis more often? Evidence from Graft-Versus-Host Disease Patients Monitored with Treg as a Biomarker

Figures & data

Figure 1. Example of flow cytometry gating strategy for Treg identification as CD3⁺, CD4⁺, CD127^- and CD25⁺⁺ cells.

Table 1. Summary of patient’s characteristics and extracorporeal photopheresis sessions.

Case	Gender	Donor	Conditioning	GvHD prophylaxis	Time to cGvHD onset (months)	Age at first ECP	ECP duration (days)	ECPs (n)	Immune evaluations (n)
Pt1	Male	MRD	MA, BuCy	CsA + MTX	13	20	2062	162	80
Pt2	Female	MRD	RIC, FluBu	CsA + MMF	9	49	1868	91	46
Pt3	Male	MRD	RIC	CsA + MMF	120	48	1178	80	38
Pt4	Male	MRD	MA, BuCy	CsA	12	44	2866	122	68
Pt5	Female	MRD	RIC, FluBu	CsA + MMF	40	47	1155	140	79
Pt6	Male	MRD	MA, BuCy	CsA + MTX	72	59	826	121	59

BuCy: Busulfan plus cyclophosphamide; cGvHD: Chronic graft-versus-host disease; CsA: Cyclosporine A; ECP: Extracorporeal photopheresis; FluBu: Fludarabine plus busulfan; GvHD: Graft-versus-host disease; MA: Myeloablative; MMF: Mycophenolate mofetil; MRD: Matched-related donor; MTX: Methotrexate; Pt: Patient; RIC: Reduced-intensity conditioning.

Figure 2. Reduction of the prednisolone scheme, in mg/day, evaluated per year under extracorporeal photopheresis.

Patient two not shown due to nonprednisolone containing scheme.

Pt: Patient.

Figure 3. Distribution of Treg in percentage, mean value per year of extracorporeal photopheresis treatment for each patient.

All responding patients had a significant increase in %Tregs comparing the first to the last year of treatment (p < 0.001). Patient three, who did not respond to extracorporeal photopheresis, had not (p = 0.19).

Pt: Patient.

Figure 4. Offline extracorporeal photopheresis protocol increases the average circulating regulatory T cell and T helper/cytotoxic T cells ratio, when compared with the online protocol in patient four, p < 0.01.

Th/Tc: T helper/cytotoxic T cell; Treg: Regulatory T cell.