Natural killer (NK) cells have multifaceted roles within the complex tumor milieu. They are pivotal components of innate immunity and shape the dynamic landscape of tumor-immune cell interactions, and thus can be leveraged for use in therapeutic interventions. NK-based immunotherapies have had remarkable success in hematological malignancies, but these therapies are met with many challenges in solid tumors, including neuroblastoma (NB), a childhood tumor arising from the sympathetic nervous system. With a focus on NB, this review outlines the mechanisms employed by NK cells to recognize and eliminate malignant cells, delving into the dynamic relationship between ligand-receptor interactions, cytokines, and other molecules that facilitate the cross talk between NK and NB cells. We discuss the immunomodulatory functions of NK cells and the mechanisms that contribute to loss of this immunosurveillance in NB, with a focus on how this dynamic has been utilized in recent immunotherapy advancements for NB.

BACKGROUND:Outcome reports for Alpha Ankle Arthroplasty (AAA), a third-generation implant relying on a mobile bearing design for total ankle replacement, are sparse. This retrospective study evaluated the midterm survivorship, clinical, and radiologic outcomes after implantation of this implant.METHODS:For 64 patients who received 65 Triple A ankle implants between 2009 and 2020, implant survival was calculated using the Kaplan-Meier curve. Clinical outcomes were evaluated by measuring the range of motion, stability, Western Ontario and McMaster Universities Osteoarthritis Questionnaire score (WOMAC), and American Orthopaedic Foot & Ankle Society ankle-hindfoot score (AOFAS). The average pain level and satisfaction with the postoperative result were rated on a numeric rating scale (0-10). Additionally, radiologic analysis was performed using anteroposterior and lateral radiographs and tibiotalar alignment was assessed.RESULTS:The implant-survival rate was 61.5% at a mean follow-up of 8.2 years. Twenty-five patients (38.5%) required revision surgery (average time to revision, 3.1 years, 95% CI 2.1-4.1 years). For patients without revisions, the average range of motion in dorsiflexion and plantarflexion were 3.6 ± 4.2 degrees and 21.9 ± 7.8 degrees, respectively. The mean WOMAC and AOFAS scores were 44.7 ± 47.5 and 75.1 ± 14.0, respectively. The average pain and subjective satisfaction scores were 2.0 ± 1.7 and 8.5 ± 1.9, respectively. Mean alignment values did not differ significantly for patients who required revision surgery.CONCLUSION:We found a high revision rate with use of the AAA. However, patients who did not require revision surgery had, on average, high satisfaction and good functional outcomes.LEVEL OF EVIDENCE:Level IV, case series.