Transfusion-related acute lung injury (TRALI) during remission induction course of acute myeloid leukemia: A possible role for all-transretinoic-acid (ATRA)?

All‑trans retinoic acid promotes macrophage phagocytosis and decreases inflammation via inhibiting CD14/TLR4 in acute lung injury

Acute lung injury (ALI) is a common clinical emergency and all-trans retinoic acid (ATRA) can alleviate organ injury. Therefore, the present study investigated the role of ATRA in ALI. Lipopolysaccharide (LPS)-induced ALI rats were treated with ATRA and the arterial partial pressure of oxygen (PaO₂), lung wet/dry weight (W/D) ratio and protein content in the bronchial alveolar lavage fluid (BALF) were measured to evaluate the effect of ATRA on ALI rats. Alveolar macrophages were isolated from the BALF. The phagocytic function of macrophages was detected using the chicken erythrocyte phagocytosis method and flow cytometry. The viability of macrophages was measured using a Cell Counting Kit-8 assay, and apoptosis was analyzed using a TUNEL assay and flow cytometry. The expression levels of Toll-like receptor 4 (TLR4) and cluster of differentiation (CD)14 on the macrophage membrane were detected by immunofluorescence staining. The protein levels of TLR4, CD14, phosphorylated (p)-65, p65, p-IκBα and IκBα were analyzed using western blotting. The concentrations of IL-6, IL-1β and macrophage inflammatory protein-2 in the plasma of rats were detected by ELISA. Macrophages were treated with IAXO-102 (TLR4 inhibitor) to verify the involvement of CD14/TLR4 in the effect of ATRA on ALI. ATRA provided protection against LPS-induced ALI, as evidenced by the increased PaO₂ and reduced lung W/D ratio and protein content in the BALF. ATRA enhanced macrophage phagocytosis and viability and reduced apoptosis and inflammation in ALI rats. Mechanically, ATRA inhibited CD14 and TLR4 expression and NF-κB pathway activation. ATRA enhanced macrophage phagocytosis and reduced inflammation by inhibiting the CD14/TLR4-NF-κB pathway in LPS-induced ALI. In summary, ATRA inactivated the NF-κB pathway by inhibiting the expression of CD14/TLR4 receptor in the alveolar macrophages of rats, thus enhancing the phagocytic function of macrophages in ALI rats, improving the activity of macrophages, inhibiting apoptosis, reducing the levels of inflammatory factors, and consequently playing a protective role in ALI model rats. This study may offer novel insights for the clinical management of ALI.

Transfusion-related acute lung injury; clinical perspectives

Transfusion-related acute lung injury (TRALI) was introduced in 1983 to describe a clinical syndrome seen within 6 h of a plasma-containing blood products transfusion. TRALI is a rare transfusion complication; however, the FDA has suggested that TRALI is the leading cause of transfusion-related mortality. Understanding the pathogenesis of TRALI will facilitate adopting preventive strategies, such as deferring high plasma volume female product donors. This review outlines the clinical features, pathogenesis, treatment, and prevention of TRALI.

Transfusion-related acute lung injury and potential risk factors among the inpatient US elderly as recorded in Medicare claims data, during 2007 through 2011

BACKGROUND

Transfusion-related acute lung injury (TRALI) is a serious complication leading to pulmonary edema and respiratory failure. This study's objective was to assess TRALI occurrence and potential risk factors among inpatient US elderly Medicare beneficiaries, ages 65 and older, during 2007 through 2011.

STUDY DESIGN AND METHODS

This retrospective claims-based study utilized large Medicare administrative databases. Transfusions were identified by recorded procedure and revenue center codes. TRALI was ascertained via ICD-9-CM diagnosis code. The study evaluated TRALI rates among the inpatient elderly overall and by calendar year, age, sex, race, blood components, and units transfused. Logistic regression analyses were used to assess potential risk factors.

RESULTS

Of 11,378,264 inpatient transfusion stays for elderly Medicare beneficiaries, 2556 had a recorded TRALI diagnosis code, an overall rate of 22.46 per 100,000 stays. TRALI rates were higher for platelet (PLT)- and plasma-containing transfusions and increased by year and number of units transfused (p < 0.0001). Significantly higher odds of TRALI were also found for persons ages 65 to 79 years versus more than 79 years (OR, 1.19; 95% confidence interval CI, 1.09-1.29), females versus males (OR, 1.26; 95% CI, 1.16-1.38), white versus nonwhite (OR, 1.43; 95% CI, 1.27-1.66), and with 6-month histories of postinflammatory pulmonary fibrosis (OR, 1.89; 95% CI, 1.52-2.20), tobacco use (OR, 1.16; 95% CI, 1.00-1.26), and other diseases.

CONCLUSION

Our study among the elderly suggests TRALI to be a severe event and identifies a substantially increased TRALI occurrence with greater number of units and with PLT- or plasma-containing transfusions. The study also suggests importance of underlying health conditions, prior recipient alloimmunization, and nonimmune mechanism in TRALI development among the elderly.

Methylprednisolone fails to attenuate lung injury in a mouse model of transfusion related acute lung injury

BACKGROUND

Transfusion-related acute lung injury (TRALI) is the leading cause of transfusion-related morbidity and mortality. Anecdotally, TRALI patients have been treated with corticosteroids. However, evidence for its therapeutic rationale in TRALI is lacking. We determined the effects of corticosteroids on lung injury in a "two-hit" mouse model of antibody-mediated TRALI.

STUDY DESIGN AND METHODS

BALB/c mice were primed with lipopolysaccharide, after which TRALI was induced by injecting major histocompatibility complex (MHC)-I antibody against H2K(d) . Mice infused with phosphate-buffered saline served as controls. Simultaneously, one group of TRALI mice was infused with methylprednisolone (MPS; 2 mg/kg). Mice were supported by mechanical ventilation for 2 hours, after which bronchoalveolar lavage fluid (BALF) and lung homogenate were obtained. Statistics were obtained by one-way analysis of variance or Kruskal-Wallis.

RESULTS

Injection of MHC-I antibodies resulted in TRALI, indicated by pulmonary edema and increased BALF levels of protein and the proinflammatory mediators macrophage inflammatory protein-2, keratinocyte-derived chemokine, and interleukin (IL)-6. Administration of MPS did not affect the amount of edema nor pulmonary protein and chemokine levels. MPS reduced systemic inflammatory reaction as well as IL-6 levels in the BALF.

CONCLUSION

In a two-hit model of antibody-mediated TRALI, MPS attenuated the IL-6 host response, but failed to prevent the development of lung injury.

Umbilical cord blood transplantation: review of factors affecting the hospitalized patient

The use of umbilical cord blood (UCB) as a stem cell donor source has dramatically increased over the last 2 decades. Patients undergoing UCB transplantation share medical management issues with patients receiving a hematopoietic stem cell transplantion using adult donor sources (peripheral blood stem cells or bone marrow stem cells) and may also have more complex medical issues that appear to be related to delayed immune recovery from UCB-derived stem cells. The interface with critical care providers is likely to occur in the transplant and posttransplant setting. Patients may experience UCB infusion reactions that range from mild to rarely severe. Following transplant, patients are transfusion dependent for long periods due to the prolonged engraftment of UCB cells. They are at high risk of infection, particularly viral. Once engrafted, UCB transplant patients have a lower rate of graft versus host disease compared to other donor sources. Some of the other complications that are seen in patients undergoing UCB transplant are posttransplant lymphoproliferative disease, diffuse alveolar hemorrhage, and posterior reversible encephalopathy will also be discussed.