HLA Associations and Risk of Posttransplant Lymphoproliferative Disorder in a Danish Population-Based Cohort

Incidence and outcome of post-transplant lymphoproliferative disorders in lung transplant patients: Analysis of ISHLT Registry

BACKGROUND

Post-transplant lymphoproliferative disorder (PTLD) is a life-threatening complication following lung transplant. We studied incidence and risk factors for PTLD in adult lung transplant recipients (LTRs) using the International Society for Heart and Lung Transplantation Registry.

METHODS

The International Society for Heart and Lung Transplantation Registry was used to identify adult, first-time, single and bilateral LTRs with at least 1 year of follow-up between 2006 and 2016. Kaplan-Meier method was used to describe the timing and distribution of PTLD. Univariable and multivariable Cox proportional hazards regression models were used to examine clinical characteristics associated with PTLD.

RESULTS

Of 19,309 LTRs in the analysis cohort, we identified 454 cases of PTLD. Cumulative incidence of PTLD was 1.1% (95% CI = 1.0%-1.3%) at 1 year and 4.1% (95% CI = 3.6%-4.6%) at 10 years. Of the PTLD cases, 47.4% occurred within the first year following lung transplantation. In the multivariable model, independent risk factors for PTLD included age, Epstein-Barr virus serostatus, restrictive lung diseases, and induction. Risk of PTLD during the first year after transplant increased with increasing age in patients between 45 and 62 years at time of transplantation; the inverse was true for ages <45 years or >62 years. Finally, receiving a donor organ with human leukocyte antigen types A1 and A24 was associated with an increased risk of PTLD, whereas the recipient human leukocyte antigen type DR11 was associated with a decreased risk.

CONCLUSIONS

Our study indicates that PTLD is a relatively rare complication among adult LTRs. We identified clinical characteristics that are associated with an increased risk of PTLD.

Microbes as Master Immunomodulators: Immunopathology, Cancer and Personalized Immunotherapies

The intricate interplay between the immune system and microbes is an essential part of the physiological homeostasis in health and disease. Immunological recognition of commensal microbes, such as bacterial species resident in the gut or lung as well as dormant viral species, i.e., cytomegalovirus (CMV) or Epstein-Barr virus (EBV), in combination with a balanced immune regulation, is central to achieve immune-protection. Emerging evidence suggests that immune responses primed to guard against commensal microbes may cause unexpected pathological outcomes, e.g., chronic inflammation and/or malignant transformation. Furthermore, translocation of immune cells from one anatomical compartment to another, i.e., the gut-lung axis via the lymphatics or blood has been identified as an important factor in perpetrating systemic inflammation, tissue destruction, as well as modulating host-protective immune responses. We present in this review immune response patterns to pathogenic as well as non-pathogenic microbes and how these immune-recognition profiles affect local immune responses or malignant transformation. We discuss personalized immunological therapies which, directly or indirectly, target host biological pathways modulated by antimicrobial immune responses.