Technical pitfalls when collecting, cryopreserving, thawing, and stimulating human T-cells.

The collection, cryopreservation, thawing, and culture of peripheral blood mononuclear cells (PBMCs) can profoundly influence T cell viability and immunogenicity. Gold-standard PBMC processing protocols have been developed by the Office of HIV/AIDS Network Coordination (HANC); however, these protocols are not universally observed. Herein, we have explored the current literature assessing how technical variation during PBMC processing can influence cellular viability and T cell immunogenicity, noting inconsistent findings between many of these studies. Amid the mounting concerns over scientific replicability, there is growing acknowledgement that improved methodological rigour and transparent reporting is required to facilitate independent reproducibility. This review highlights that in human T cell studies, this entails adopting stringent standardised operating procedures (SOPs) for PBMC processing. We specifically propose the use of HANC's Cross-Network PBMC Processing SOP, when collecting and cryopreserving PBMCs, and the HANC member network International Maternal Pediatric Adolescent AIDS Clinical Trials (IMPAACT) PBMC Thawing SOP when thawing PBMCs. These stringent and detailed protocols include comprehensive reporting procedures to document unavoidable technical variations, such as delayed processing times. Additionally, we make further standardisation and reporting recommendations to minimise and document variability during this critical experimental period. This review provides a detailed overview of the challenges inherent to a procedure often considered routine, highlighting the importance of carefully considering each aspect of SOPs for PBMC collection, cryopreservation, thawing, and culture to ensure accurate interpretation and comparison between studies.

Engineering the Signal Resolution of a Paper-Based Cell-Free Glutamine Biosensor with Genetic Engineering, Metabolic Engineering, and Process Optimization.

Specialized cancer treatments have the potential to exploit glutamine dependence to increase patient survival rates. Glutamine diagnostics capable of tracking a patient's response to treatment would enable a personalized treatment dosage to optimize the tradeoff between treatment success and dangerous side effects. Current clinical glutamine testing requires sophisticated and expensive lab-based tests, which are not broadly available on a frequent, individualized basis. To address the need for a low-cost, portable glutamine diagnostic, this work engineers a cell-free glutamine biosensor to overcome assay background and signal-to-noise limitations evident in previously reported studies. The findings from this work culminate in the development of a shelf-stable, paper-based, colorimetric glutamine test with a high signal strength and a high signal-to-background ratio for dramatically improved signal resolution. While the engineered glutamine test is important progress towards improving the management of cancer and other health conditions, this work also expands the assay development field of the promising cell-free biosensing platform, which can facilitate the low-cost detection of a broad variety of target molecules with high clinical value.

Long-term follow-up of VIALE-A: Venetoclax and azacitidine in chemotherapy-ineligible untreated acute myeloid leukemia.

Venetoclax-azacitidine is approved for treatment of patients with newly diagnosed acute myeloid leukemia (AML) ineligible for intensive chemotherapy based on the interim overall survival (OS) analysis of the VIALE-A study (NCT02993523). Here, long-term follow-up is presented to address survival benefit and long-term outcomes with venetoclax-azacitidine. Patients with newly diagnosed AML who were ineligible for intensive chemotherapy were randomized 2:1 to receive venetoclax-azacitidine or placebo-azacitidine. OS was the primary endpoint; complete remission with/without blood count recovery (CR/CRi) was a key secondary endpoint. This final analysis was conducted when 100% of the predefined 360 OS events occurred. In VIALE-A, 431 patients were enrolled to venetoclax-azacitidine (n = 286) or placebo-azacitidine (n = 145). At 43.2 months median follow-up, median OS was 14.7 months (95% confidence interval [CI], 12.1-18.7) with venetoclax-azacitidine, and 9.6 months (95% CI, 7.4-12.7) with placebo-azacitidine (hazard ratio, 0.58 [95% CI, 0.47-0.72], p < .001); the estimated 24-month OS rate was 37.5% and 16.9%, respectively. Median OS for patients with IDH1/2 mutations and those with measurable residual disease responses was reached in this final analysis. CR/CRi rate was similar to interim analysis. Any-grade hematologic and gastrointestinal adverse events were most common in venetoclax-azacitidine and placebo-azacitidine arms, including thrombocytopenia (47% and 42%) and neutropenia (43% and 29%). No new safety signals were identified. Long-term efficacy and safety confirm venetoclax-azacitidine is an improvement in standard-of-care for patients with AML who are not eligible for intensive chemotherapy because of advanced age or comorbidities.

The Role of Temperature, Wind Speed, and Precipitation on the Abundance of Culex Species and West Nile Virus Infection Rate in Rural West-Central Illinois.

While most research on West Nile virus (WNV) and its main vector, the Culex mosquito, has been conducted in laboratory or urban settings, studies with field-caught mosquitoes in rural areas, such as west-central Illinois, are lacking. The objective of this research was to investigate key abiotic factors using macroclimate data, including temperature, precipitation, and wind speed, to determine their influence on field-caught mosquito abundance in 4 rural counties in Illinois from 2014 to 2016. Additionally, the relationship between minimum infection rate (MIR) and thermal time was examined. Using gravid traps at 15 sites, Culex mosquitoes were collected twice a week. A total of 5,255 adult female Culex mosquitoes (Cx. pipiens, Cx. quinquefasciatus, and Cx. restuans) were collected in 2014; 9,138 in 2015; and 5,702 in 2016. Regression models were developed based on outcomes of relationships between field-caught mosquitoes and abiotic factors. Precipitation and thermal time had the most significant relationship with mosquito abundance (r2 = 0.993 and r2 = 0.993, respectively), while wind speed was less (r2 = 0.714). The greatest number of Culex and the highest annual MIR were observed in 2015, which was also the driest of the 3 sampling seasons. Mosquito abundance was observed to increase with warmer degree days and MIR was found to increase with abundance in mosquitoes. These models can be used for other mosquito surveillance and monitoring studies in various climate types and environments.

A review of the distal femur in Australopithecus.

In 1938, the first distal femur of a fossil Australopithecus was discovered at Sterkfontein, South Africa. A decade later, another distal femur was discovered at the same locality. These two fossil femora were the subject of a foundational paper authored by Kingsbury Heiple and Owen Lovejoy in 1971. In this paper, the authors discussed functionally relevant anatomies of these two fossil femora and noted their strong affinity to the modern human condition. Here, we update this work by including eight more fossil Australopithecus distal femora, an expanded comparative dataset, as well as additional linear measurements. Just as Heiple and Lovejoy reported a half-century ago, we find strong overlap between modern humans and cercopithecoids, except for inferiorly flattened condyles and a high bicondylar angle, both of which characterize modern humans and Australopithecus and are directly related to striding bipedalism. All other measured aspects of the femora are by-products of these key morphological traits. Additional fossil material from the early Pliocene will help to inform the evolution of the hominin distal femur and its condition in the Pan-Homo common ancestor that preceded bipedal locomotion.

Loperamide Misuse Mimicking Symptoms of Severe Malnutrition.

Loperamide, an oral over-the-counter µ-opioid receptor agonist used to treat diarrhea, acts primarily in the gut and, when used as recommended, has little to no systemic effect. At high doses, it may cause a "high" like other opioids. Recent literature describes an increasing incidence of loperamide misuse and overdose in the setting of the US opioid epidemic. In this case, we describe a 16-year-old with anorexia nervosa who developed dizziness, syncope, and constipation at the time of weight loss. These symptoms were originally attributed to malnutrition; however, after weight restoration, her symptoms worsened. She did not respond to initial management of suspected postural orthostatic tachycardia syndrome (POTS). She then developed acute urinary retention requiring hospitalization. Her symptoms were ultimately found to be caused by chronic surreptitious high-dose loperamide use. Her symptoms rapidly improved after cessation. This case illustrates the non-specific symptoms associated with loperamide misuse and the potential overlap with other common adolescent conditions. Adolescent medicine clinicians must be aware of the signs and symptoms of loperamide misuse as well as familiar with recommendations for both the management of acute complications and the treatment of the substance misuse.

Long-Term Safety and Efficacy of Initial and Repeat Treatment Courses With Zuranolone in Adult Patients With Major Depressive Disorder: Interim Results From the Open-Label, Phase 3 SHORELINE Study.

Objective: Zuranolone is a positive allosteric modulator of both synaptic and extrasynaptic γ-aminobutyric acid (GABA) type A receptors and a neuroactive steroid approved in the United States as an oral, once-daily, 14-day treatment course for adults with postpartum depression and under investigation for adults with major depressive disorder (MDD). Interim results from the open-label, longitudinal, phase 3 SHORELINE Study (NCT03864614) that evaluated the long-term safety and efficacy of zuranolone in adults with MDD are reported.Methods: This interim report includes patients who were enrolled and had the opportunity to be on study for up to 1 year between February 2019 and September 2021. Adults aged 18-75 years with MDD diagnosed per DSM-5 criteria and a 17-item Hamilton Rating Scale for Depression (HAMD-17) total score ≥ 20 received an initial 30-mg or 50-mg 14-day zuranolone course. HAMD-17 responders (≥ 50% reduction from baseline) at Day (D)15 of the initial treatment period were allowed to continue in the study beyond D28 and were followed up for ≤ 1 year, during which repeat treatment courses were permitted. The primary endpoint was safety and tolerability of the initial and repeat treatment courses through 1 year. Secondary endpoints included change from baseline (CFB) in HAMD-17 total score and need for repeat treatment course(s).Results: As of September 2021, among patients in the 30-mg (n = 725) and 50-mg (n = 199) Cohorts who received a zuranolone dose, 493 (68.0%) and 137 (68.8%), respectively, reported a treatment-emergent adverse event (TEAE); most patients who experienced TEAEs reported mild/moderate events (30-mg Cohort, 90.9% [448/493]; 50-mg Cohort, 85.4% [117/137]). Mean (standard deviation) CFB HAMD-17 total score at D15 of the initial treatment period was -15.2 (7.1) and -16.0 (6.0) for the 30-mg and 50-mg Cohorts, respectively; similar improvements were observed after repeat treatment courses. The proportion of patients who received only 1 treatment course during their time on study was 42.9% (210/489) in the 30-mg Cohort and 54.8% (80/146) in the 50-mg Cohort; 57.1% (279/489) and 45.2% (66/146) patients, respectively, received 2-5 total treatment courses. The majority of patients who initially responded to zuranolone received ≤ 2 total treatment courses (30-mg Cohort, 68.5% [335/489]; 50-mg Cohort, 79.5% [116/146]).Conclusions: Of patients who experienced TEAEs, most reported mild or moderately severe events, and responders to zuranolone experienced improvements in depressive symptoms with initial and repeat treatment courses.Trial Registration: ClinicalTrials.gov identifier: NCT03864614.

The Mental Health Implications of Obstetric Brachial Plexus Injuries (OBPI) on Parents.

BACKGROUND: Obstetric brachial plexus injuries (OBPI) can have mental health implications on parents coping with this injury to their newborn. The purpose of this study was to assess the mental health of mothers with newborns with an OBPI and identify resources that can help screen and treat mental health needs. MATERIAL AND METHODS: Three groups of mothers were prospectively given a self-reported survey: 1) Newborns with OBPI; 2) Newborns in the nursery without OBPI; 3) Newborns in the neonatal intensive care unit (NICU). The survey consisted of demographic questions, the PHQ-9 and PCL-S screening tools, and parents' exposure to community violence, family support and use of drugs or alcohol. RESULTS: Fifty-seven mothers were prospectively enrolled, and 30% (17/57) of mothers screened in for post-traumatic stress disorder (PTSD). OBPI mothers had significantly higher rates of PTSD symptoms when compared to mothers of children in the full-term nursery (difference = 36.4%; p < 0.01). No statistically significant difference was found between groups regarding depression symptoms. CONCLUSIONS: OBPI can be very difficult to cope with for parents and family members. Forty-two percent of mothers with newborns with OBPI or children in the NICU screened in for PTSD symptoms. OBPI clinics should be staffed similarly to the NICU with clinical social workers to appropriately screen and treat parents with PTSD and depression symptoms.

Effect of Bergenin on Human Gingival Fibroblast Response on Zirconia Implant Surfaces: An In Vitro Study.

The poor quality of life associated with the loss of teeth can be improved by the placing of dental implants. However, successful implantation relies on integration with soft tissues or peri-implant inflammatory disease that can lead to the loss of the implant. Pharmacological agents, such as antibiotics and antiseptics, can be used as adjunct therapies to facilitate osseointegration; however, they can have a detrimental effect on cells, and resistance is an issue. Alternative treatments are needed. Hence, this study aimed to examine the safety profile of bergenin (at 2.5 µM and 5 µM), a traditional medicine, towards human gingival fibroblasts cultured on acid-etched zirconia implant surfaces. Cellular responses were analysed using SEM, resazurin assay, and scratch wound healing assay. Qualitative assessment was conducted for morphology (day 1) and attachment (early and delayed), and quantitative evaluation for proliferation (day 1, 3, 5 and 7), and migration (0 h, 6 h and 24 h). The concentrations of bergenin at 2.5 µM and 5 µM did not demonstrate a statistically significant effect with regard to any of the cellular responses (p > 0.05) tested. In conclusion, bergenin is non-cytotoxic and is potentially safe to be used as a local pharmacological agent for the management of peri-implant inflammatory diseases.

Utilization of street-based COVID-19 vaccination clinics in Phoenix's homeless population.

The novel Coronavirus (COVID-19) is a highly contagious viral illness that has caused the most significant global health crisis in recent human history. Individuals experiencing homelessness represent one of the more vulnerable populations for COVID-19 infection and morbidity. Amongst individuals experiencing homelessness in Phoenix, a student-led interprofessional organization called Street Medicine Phoenix (SMP) sought to both reduce the risk of COVID-19 transmission and morbidity/mortality related to infection. Through collaborations with the Maricopa County Department of Public Health and various community organizations, SMP developed a format for street-based vaccination clinics. SMP deployed these clinics on numerous occasions to the streets directly surrounding the community homeless shelter, allowing SMP to vaccinate individuals directly in their encampments. Through SMP's efforts starting in February 2021, 400 individuals experiencing homelessness have received at least one COVID-19 vaccine. Challenges encountered included low health literacy, lack of established rapport and trust, low vaccine confidence, difficulty verifying patients' vaccination status, difficulty obtaining sufficient information from patients to create a record in the Arizona State Immunization Information System (ASIIS), monitoring patients post-vaccination, transporting vaccine supplies from encampment to encampment, and lack of patient awareness of the mobile vaccine clinic services. Despite challenges, SMP's outreach efforts have demonstrated the feasibility and importance of mobile public health services to reach homeless encampments, particularly mobile vaccination clinics in response to disease outbreaks, and the necessity of strategic partnerships with community agencies to effectively meet the needs of underserved populations.

Insights into Spt6: a histone chaperone that functions in transcription, DNA replication, and genome stability.

Transcription elongation requires elaborate coordination between the transcriptional machinery and chromatin regulatory factors to successfully produce RNA while preserving the epigenetic landscape. Recent structural and genomic studies have highlighted that suppressor of Ty 6 (Spt6), a conserved histone chaperone and transcription elongation factor, sits at the crux of the transcription elongation process. Other recent studies have revealed that Spt6 also promotes DNA replication and genome integrity. Here, we review recent studies of Spt6 that have provided new insights into the mechanisms by which Spt6 controls transcription and have revealed the breadth of Spt6 functions in eukaryotic cells.

The Role of Autopsy in Quality Assurance: Pilot Study of a Method for Prospective Reporting of Diagnostic Errors Discovered at Autopsy.

ABSTRACT: Hospital autopsies frequently reveal errors in diagnosis that could have affected the patient's clinical outcome. The aims of this study were (1) to investigate the ability of autopsy at our institution to elucidate unrecognized antemortem diagnoses and (2) to pilot a method for tabulating diagnostic discrepancies on a prospective basis. The study sample consisted of 296 cases from our hybrid hospital/forensic autopsy service during the period 2016 to 2018. Discrepancies in autopsy and clinical diagnosis were reported by pathologists at the time of autopsy report generation using a standard form. The rates of major discrepancies between autopsy and clinical diagnoses were 37.5% for in-hospital cases and 25% for patients who died outside our hospital (P < 0.05). The most common discrepant category was infection. The overall rates of discrepant causes of death were 14% (in hospital) and 8% (out of hospital) (ns). Overall percentages of cases with major diagnostic discrepancies were higher in our study than have been previously reported. It is possible that the nature of our patient population plays a role in this result. This study describes an important prospective reporting tool that will allow us to track rates of medical errors and improve diagnosis and treatment of the critically ill.

Hominin fossils from Kromdraai and Drimolen inform Paranthropus robustus craniofacial ontogeny.

Ontogeny provides critical information about the evolutionary history of early hominin adult morphology. We describe fossils from the southern African sites of Kromdraai and Drimolen that provide insights into early craniofacial development in the Pleistocene robust australopith Paranthropus robustus. We show that while most distinctive robust craniofacial features appear relatively late in ontogeny, a few do not. We also find unexpected evidence of independence in the growth of the premaxillary and maxillary regions. Differential growth results in a proportionately larger and more postero-inferiorly rotated cerebral fossa in P. robustus infants than in the developmentally older Australopithecus africanus juvenile from Taung. The accumulated evidence from these fossils suggests that the iconic SK 54 juvenile calvaria is more likely early Homo than Paranthropus. It is also consistent with the hypothesis that P. robustus is more closely related to Homo than to A. africanus.

Mpox Case Reports in an Urban Homeless Population and a Proof of Concept for a Street-Based Mobile Mpox Vaccination Clinic.

Mpox is a new public health outbreak that particularly threatens the homeless population. Street Medicine Phoenix (SMP) is a student-led interprofessional volunteer organization that provides medical care and other essential services to individuals experiencing homelessness in Phoenix, Arizona. In addition to core services such as wound care; health screenings (blood pressure and blood glucose.); vision screenings; HIV testing; naloxone education and distribution; flu, COVID-19, and Hepatitis A vaccinations; and community resource referrals, SMP began offering mpox education and vaccination at outreach events. During an outreach event shortly after the onset of the mpox outbreak, SMP identified 2 suspected mpox cases. Accordingly, SMP has partnered with the Maricopa County Public Health Department to set up mobile mpox vaccination clinics on the streets outside of Phoenix Arizona's largest homeless shelter. We share the details of these 2 cases along with our early efforts vaccinating individuals experiencing homelessness for mpox via our mobile vaccination clinic. Our experiences demonstrate the importance of community agencies providing direct outreach to underserved populations where they are at, particularly the homeless population, to address public health concerns such as emerging disease outbreaks like mpox. In addition, these cases highlight the potential significant impact that street medicine programs can have on their respective homeless communities in the context of infectious disease mitigation and emphasize the importance of partnerships with local health departments.

Distribution of Invasive Aedes Mosquitoes in West-Central Illinois, 2014-18: Record Updates for Aedes japonicus and Ae. albopictus.

A comprehensive surveillance of Aedes mosquitoes in west-central Illinois has not been conducted in recent years, resulting in incomplete distribution records for several Illinois counties. As of 2014, out of 102 Illinois counties, active populations of Ae. japonicus had been confirmed in 15 counties, and Ae. albopictus confirmed in 34 counties. The Miller laboratory at Western Illinois University (WIU) began the WIU Vector Biology Initiative (WIU-VBI) in 2014 to address the lack of mosquito surveillance in west-central Illinois. Through this effort, the presence of Ae. japonicus was confirmed for the 1st time in Fulton, Hancock, and Schuyler counties, IL, from 2014 to 2018. Actively breeding populations were confirmed in Cass, Fulton, McDonough, and Schuyler counties, IL. Additionally, Ae. albopictus was observed for the 1st time in Cass, Fulton, Hancock, McDonough, and Schuyler counties, IL, in 2016 and 2017, with active breeding populations in Cass and McDonough counties, IL.

Student-led interprofessional global health course: learning impacts during a global crisis.

BACKGROUND: This study assesses the impact of the Interprofessional Global Health Course (IPGHC) on students' fundamental global health knowledge and personal viewpoints on global health domains. It explores the evolution of students' understanding of global health specifically in relation to the COVID-19 pandemic. METHODS: Ninety-nine students were selected from 123 McGill student applicants based on their motivation and commitment to take part in IPGHC's ten-week 2020 curriculum. These IPGHC students were eligible to participate in the study. The study's design is sequential explanatory mixed methods. The cross-sectional survey (quantitative phase) appraises students' global health learning outcomes using pre- and post-course surveys, with the use of 5-point Likert-scale questions. The descriptive qualitative survey (qualitative phase) further explores the impact of IPGHC on student's understanding of global health and the reflections of students on the COVID-19 pandemic after IPGHC. The post-course survey included a course evaluation for quality improvement purposes. RESULTS: Of the 99 students, 81 students across multiple undergraduate and graduate disciplines participated in the study by completing the course surveys. Mean knowledge scores of the following 11 global health topics were increased between pre- and post-course survey: Canadian Indigenous health (P < 0.001), global burden of disease (P < 0.001), global surgery (P < 0.001), infectious diseases and neglected tropical diseases (P < 0.001), refugee and immigrant health (P < 0.001), research and development of drugs (P < 0.001), role of politics and policies in global health (P = 0.02), role of technology in global health (P < 0.001), sexual violence (P < 0.001), systemic racism in healthcare (P = 0.03), and trauma in the global health context (P < 0.001). A positive change in student viewpoints was observed in response to questions regarding their perception of the importance of global health education in their own professional health care programs (P < 0.001), and their understanding of the roles and responsibilities of other healthcare professionals (P < 0.001). In the post-course survey open-ended questions, students exemplified their knowledge gained during the course to create a more informed definition of global health. Several recurring themes were identified in the student reflections on the COVID-19 pandemic, notably policy and politics, followed by access to healthcare and resources. CONCLUSION: This study emphasizes the need for interprofessional global health education at the university level and demonstrates how rapidly global health learners can apply their knowledge to evolving contexts like the COVID-19 pandemic.

The conserved histone chaperone Spt6 is strongly required for DNA replication and genome stability.

Histone chaperones are an important class of proteins that regulate chromatin accessibility for DNA-templated processes. Spt6 is a conserved histone chaperone and key regulator of transcription and chromatin structure. However, its functions outside of these roles have been little explored. In this work, we demonstrate a requirement for S. cerevisiae Spt6 in DNA replication and, more broadly, as a regulator of genome stability. Depletion or mutation of Spt6 impairs DNA replication in vivo. Additionally, spt6 mutants are sensitive to DNA replication stress-inducing agents. Interestingly, this sensitivity is independent of the association of Spt6 with RNA polymerase II (RNAPII), suggesting that spt6 mutants have a transcription-independent impairment of DNA replication. Specifically, genomic studies reveal that spt6 mutants have decreased loading of the MCM replicative helicase at replication origins, suggesting that Spt6 promotes origin licensing. Our results identify Spt6 as a regulator of genome stability, at least in part through a role in DNA replication.

Racial Differences in Postoperative Opioid Prescribing Practices in Spine Surgical Patients.

BACKGROUND: As the opioid epidemic accelerates in the United States, numerous sociodemographic factors have been implicated its development and are, furthermore, a driving factor of the disparities in postoperative pain management. Recent studies have suggested potential associations between the influence of race and ethnicity on pain perception but also the presence of unconscious biases in the treatment of pain in minority patients. OBJECTIVE: To characterize the perioperative opioid requirements across racial groups after spine surgery. METHODS: A retrospective, observational study of 1944 opioid-naive adult patients undergoing a neurosurgical spine procedure, from June 2012 to December 2019, was performed at a large, quaternary care institute. Postoperative inpatient and outpatient opioid usage was measured by oral morphine equivalents, across various racial groups. RESULTS: Case characteristics were similar between racial groups. In the postoperative period, White patients had shorter lengths of stay compared with Black and Asian patients ( P < .05). Asian patients used lower postoperative inpatient opioid doses in comparison with White patients ( P < .001). White patients were discharged with significantly higher doses of opioids compared with Black patients ( P < .01); however, they were less likely to be readmitted within 30 days of discharge ( P < .01). CONCLUSION: In a large cohort of opioid-naive postoperative neurosurgical patients, this study demonstrates higher inpatient and outpatient postoperative opioid usage among White patients. Increasing physician awareness to the effect of race on inpatient and outpatient pain management would allow for a modified opioid prescribing practice that ensures limited yet effective opioid dosages void of implicit biases.

Bone Tissue Engineering Scaffolds: Function of Multi-Material Hierarchically Structured Scaffolds.

Bone tissue engineering (BTE) is a topic of interest for the last decade, and advances in materials, processing techniques, and the understanding of bone healing pathways have opened new avenues of research. The dual responsibility of BTE scaffolds in providing load-bearing capability and interaction with the local extracellular matrix to promote bone healing is a challenge in synthetic scaffolds. This article describes the usage and processing of multi-materials and hierarchical structures to mimic the structure of natural bone tissues to function as bioactive and load-bearing synthetic scaffolds. The first part of this literature review describes the physiology of bone healing responses and the interactions at different stages of bone repair. The following section reviews the available literature on biomaterials used for BTE scaffolds followed by some multi-material approaches. The next section discusses the impact of the scaffold's structural features on bone healing and the necessity of a hierarchical distribution in the scaffold structure. Finally, the last section of this review highlights the emerging trends in BTE scaffold developments that can inspire new tissue engineering strategies and truly develop the next generation of synthetic scaffolds.