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Background The Wnt/β-catenin signaling pathway is a major target of p53. β-Catenin/p53 coexpression predicts poorer survival in carcinoma patients. Conversely, CD99 inhibits tumor metastasis through the Wnt/β-catenin pathway. We therefore assessed p53, β-catenin, and CD99 by immunohistochemistry. Patients and Methods We studied 45 patients with systemic anaplastic large-cell lymphoma (ALCL), including 20 anaplastic lymphoma kinase (ALK)-positive and 25 ALK-negative ALCL. β-Catenin expression was analyzed using phospho-β-catenin-S552 antibody because its nuclear localization indicates Wnt signaling. Results In this cohort, p53 expression was associated with ALK-negative ALCL. Furthermore, p53 or β-catenin expression alone or β-catenin/p53 double expression showed poorer overall survival and disease-free survival in patients with ALCL overall and in patients with ALK-negative ALCL. CD99 expression was more frequent in ALK-positive ALCL but had no prognostic significance. Conclusion This is the first study to evaluate phospho-β-catenin-S552 expression in ALCL. The results of this study, although limited by small patient size, suggest that β-catenin and p53 may play a role in pathogenesis and may be helpful in risk stratification of ALCL patients.

Nanoparticles (NPs) play expanding roles in biomedical applications including imaging and therapy, however, their long-term fate and clearance profiles have yet to be fully characterized in vivo. NP delivery via the airway is particularly challenging, as the clearance may be inefficient and lung immune responses complex. Thus, specific material design is required for cargo delivery and quantitative, noninvasive methods are needed to characterize NP pharmacokinetics. Here, biocompatible poly(acrylamidoethylamine)-b-poly(DL-lactide) block copolymer-based degradable, cationic, shell-cross-linked knedel-like NPs (Dg-cSCKs) were employed to transfect plasmid DNA. Radioactive and optical beacons were attached to monitor biodistribution and imaging. The preferential release of cargo in acidic conditions provided enhanced transfection efficiency compared to non-degradable counterparts. In vivo gene transfer to the lung was correlated with NP pharmacokinetics by radiolabeling Dg-cSCKs and performing quantitative biodistribution with parallel positron emission tomography and Čerenkov imaging. Quantitation of imaging over 14 days corresponded with the pharmacokinetics of NP movement from the lung to gastrointestinal and renal routes, consistent with predicted degradation and excretion. This ability to noninvasively and accurately track NP fate highlights the advantage of incorporating multifunctionality into particle design.

Early immune responses are important in shaping long-term outcomes of human lung transplants. To examine the role of early immune responses in lung rejection and acceptance we developed a method to retransplant mouse lungs. Retransplantation into T cell-deficient hosts showed that for lungs and hearts alloimmune responses occurring within 72 hours of transplantation are reversible. In contrast to hearts, a 72-hour period of immunosuppression with costimulation blockade in primary allogeneic recipients suffices to prevent rejection of lungs upon retransplantation into untreated allogeneic hosts. Long-term lung acceptance is associated with induction of bronchus-associated lymphoid tissue, where Foxp3+ cells accumulate and recipient T cells interact with CD11c+ dendritic cells. Acceptance of retransplanted lung allografts is abrogated by treatment of immunosuppressed primary recipients with anti-CD25 antibodies. Thus, events contributing to lung transplant acceptance are established early in the graft and induction of bronchus-associated lymphoid tissue can be associated with an immune quiescent state.

Silver is a centuries old antibiotic agent currently used to treat infected burns. The sensitivity of a wide range of drug-resistant microorganisms to silver killing suggests that it may be useful for treating refractory lung infections. Toward this goal, we previously developed a methylated caffeine silver acetate compound, SCC1, that exhibits broad-spectrum antimicrobial activity against clinical strains of bacteria in vitro and when nebulized to lungs in mouse infection models. Preclinical testing of high concentrations of SCC1 in primary culture mouse tracheal epithelial cells (mTEC) showed selective ciliated cell death. Ciliated cell death was induced by both silver- and copper-containing compounds, but not by the methylated caffeine portion of SCC1. We hypothesized that copper transporting P-type ATPases, ATP7A and ATP7B, play a role in silver detoxification in the airway. In mTEC, ATP7A was expressed in non-ciliated cells, whereas ATP7B was expressed only in ciliated cells. The exposure of mTEC to SCC1 induced the trafficking of ATP7B, but not ATP7A, suggesting the presence of a cell-specific silver uptake and detoxification mechanisms. Indeed, the expression of the copper uptake protein CTR1 was also restricted to ciliated cells. A role of ATP7B in silver detoxification was further substantiated when treatment of SCC1 significantly increased cell death in ATP7B shRNA treated HepG2 cells. Additionally, mTEC from ATP7B-/- mice showed enhanced loss of ciliated cells compared to wild type. These studies are the first to demonstrate a cell-type specific expression of the Ag+/Cu+ transporters ATP7A, ATP7B and CTR1 in airway epithelial cells, and a role for ATP7B in detoxification of these metals in the lung.