Pretransplant T-cell immune imbalance predicts slow engraftment after autologous hematopoietic stem cell transplantation in lymphoma

Abstract

BACKGROUND

Autologous hematopoietic stem cell transplantation (auto-HSCT) is a cornerstone therapeutic strategy for lymphoma. Slow engraftment after auto-HSCT increases the risks of infection and hemorrhage, prolongs hospital stay, and is therefore a critical determinant of transplant safety and clinical outcomes. To date, clinical evidence on risk factors for slow engraftment after auto-HSCT in patients with lymphoma remains insufficient, particularly regarding the pretransplant immune microenvironment and lymphocyte subsets.

AIM

To explore clinical and immune risk factors and construct a prediction model for slow engraftment after auto-HSCT in patients with lymphoma.

METHODS

We retrospectively enrolled 166 patients with lymphoma who underwent auto-HSCT at two Chongqing centers from July 2022 to June 2025. Patients were divided into slow engraftment (neutrophil engraftment > 10 days or platelet engraftment > 12 days, based on the median times) and early engraftment groups. Baseline clinical features, transplantation parameters, pretransplant lymphocyte subsets, and inflammatory cytokines were collected. Univariate and multivariate logistic regression analyses were used to identify independent risk factors, construct a combined predictive model, and assess its performance.

RESULTS

Multivariate analysis identified advanced age, reinfused CD34+ cell dose < 3.5 × 10⁶/kg, a higher proportion of CD8+ T cells, a lower absolute CD4+ T-cell count, and prolonged peritransplant fever as independent risk factors for slow engraftment after auto-HSCT in lymphoma patients. Patients receiving a high CD34+ cell dose (≥ 3.5 × 10⁶/kg) achieved faster neutrophil and platelet engraftment than those in the low-dose group. Compared with patients with early engraftment, those with slow engraftment showed pretransplant T-cell subset imbalance and elevated interleukin-2 and interferon-γ levels. A prediction model integrating these variables demonstrated good predictive performance and outperformed individual indicators, achieving an area under the curve (AUC) of 0.780 for identifying patients at risk of slow engraftment after auto-HSCT.

CONCLUSION

Slow engraftment after auto-HSCT is associated with clinical and immune factors. Pretransplant T-cell imbalance predicts delayed engraftment, and a combined model improves risk prediction (AUC = 0.780).

Keywords: Autologous hematopoietic stem cell transplantation; Slow engraftment; T lymphocyte subsets; T-cell immune imbalance; Risk factor; Lymphoma

Core Tip: This retrospective study enrolled 166 lymphoma patients undergoing autologous hematopoietic stem cell transplantation. Advanced age, low CD34+ cell dose, prolonged peritransplant fever, and pretransplant Tcell immune imbalance were independent risk factors for slow engraftment. A combined predictive model (area under the curve = 0.780) showed good performance. Pretransplant immune evaluation helps identify high-risk patients and improve transplant safety.