Results of a Multi-institutional Randomized Phase 3 Trial of Parotid-Sparing Whole Brain Radiotherapy

PURPOSE/OBJECTIVE(S)

Observational studies have reported that xerostomia is common after conventional whole brain radiotherapy (WBRT) and associated with parotid dose. In this multi-institutional, single-blind randomized controlled trial, we hypothesized that patient-reported xerostomia is reduced in patients randomized to parotid-sparing vs. standard WBRT fields.

MATERIALS/METHODS

Between 2018 and 2021, patients receiving conventional WBRT (30-35 Gy in 10-15 fractions) for any diagnosis were enrolled at 3 academic institutions. Patients were randomized between standard WBRT fields covering the C1 vertebra with no prospective parotid delineation (control) vs. parotid-sparing fields without C1 coverage (experimental). Patients completed the University of Michigan Xerostomia Questionnaire (Scored 0-100, higher is worse) at baseline, EndRT, 2 weeks, 1 month, 3 months, and 6 months. Patients were excluded from toxicity analyses if baseline xerostomia score was >50 or if they did not complete any post-baseline questionnaires. The primary endpoint was proportion of patients with ≥15 point absolute increase in xerostomia score from baseline to 1 month; 108 patients were needed for an 80% power to detect a 22% absolute difference (1-sided significance of 0.05). The secondary endpoint was the rate of marginal failures.

RESULTS

The study closed early after 56 patients were randomized. Median survival was 4.6 months. 46 patients (23 in each arm) were eligible for analysis. Mean parotid dose was 17 vs. 10 Gy in the standard vs. parotid-sparing arms, respectively. The table below shows mean xerostomia score and proportion of patients with ≥15 increase in xerostomia score at each time point. There was no difference in the proportion of patients experiencing ≥15 increase in xerostomia score at 1 month, though there was a trend toward lower xerostomia score at 1 month in patients randomized to parotid-sparing fields (p = 0.07, Table). Xerostomia rates were also significantly improved in the parotid-sparing arm at EndRT (p = 0.03), but no longer-term difference was observed with greater attrition at 3 and 6 months. On linear regression, there was a trend toward association between mean parotid dose and xerostomia score at 1 month (p = 0.06). There were no reported marginal failures in either arm.

CONCLUSION

Parotid-sparing without coverage of the C1 vertebra appears safe and may meaningfully reduce acute xerostomia in patients with limited life expectancy who are candidates for conventional WBRT, although the study was underpowered to detect a significant difference at 1 month.

Exploring barriers to vaccine delivery in adult migrants: a qualitative study in primary care

Background

The COVID-19 pandemic has highlighted shortfalls in the delivery of vaccine programmes to older migrant groups. Guidelines exist, however, little is known around care pathways and engagement of these older cohorts in routine vaccinations in primary care, including catch-up programmes. We explored the views of primary care professionals around barriers and facilitators to catch-up vaccination in adult migrants (defined as foreign born; 18+ years) with incomplete or uncertain vaccination status.

Methods

We did a qualitative interview study with purposive sampling and thematic analysis in UK primary care (50 practices included nationally; 1 hour qualitative interviews) with 64 primary care professionals (PCPs): 48 clinical staff including GPs, Practice Nurses and healthcare assistants (HCAs); 16 administrative staff including practice managers and receptionists (mean age 45 years; 84.4% female; a range of ethnicities).

Results

Participants highlighted direct and indirect barriers to catch-up vaccines in adult migrants who may have missed vaccines as children, missed boosters, and not be aligned with the UK's vaccine schedule, from both a personal and service-delivery level, with themes including: lack of training and knowledge of guidance around catch-up vaccination among staff; unclear or incomplete vaccine records; and lack of incentivization (including financial reimbursement) and dedicated time and care pathways. Adult migrants were reported as being excluded from many vaccination initiatives, most of which focus exclusively on children. PCPs noted that migrants expressed to them a range of views around vaccines, from positivity to uncertainty, to refusal.

Conclusions

Vaccine uptake in adult migrants could be improved through implementing new financial incentives, strengthening care pathways and training, and working directly with local community groups to improve understanding around the benefits of vaccination at all ages.

Key messages

The use of social media platforms by migrant populations during the COVID-19 pandemic

Background

The rapid expansion of internet and social media use has meant that both useful and potentially harmful health information can spread rapidly. Groups experiencing barriers to health systems may be more reliant on social media as a source of health information. We did a systematic review to determine the extent and nature of social media use in migrant and ethnic minority communities for COVID-19 information, and implications for preventative health measures including vaccination intent and uptake.

Methods

We reviewed published and grey literature following PRISMA guidelines (PROSPERO registered CRD42021259190). Global research was included that reported on the use of social media by migrants and/or ethnic minority groups in relation to COVID-19.

Results

1849 unique records were screened, and 21 data sources included in our analysis involving studies from the UK, US, China, Jordan, Qatar, and Turkey. We found evidence of consistent use of a range of social media platforms for COVID-19 information in some migrant and ethnic minority populations (including WeChat, Facebook, WhatsApp, Instagram, Twitter, YouTube), which may stem from difficulty in accessing COVID-19 information in their native languages or from trusted sources. There were positive and negative associations with social media use reported, with some evidence suggesting circulating misinformation and social media use may be associated with lower participation in preventative health measures, including vaccine intent and uptake, findings of which are likely relevant to multiple population groups.

Conclusions

Urgent actions and further research are now needed to better understand the use of social media platforms for accessing health information by groups who may be marginalised from health systems, effective approaches to tackling circulating misinformation, and to seize on opportunities to make better use of social media platforms to support public health communication.

Key messages

Strategies to increase catch-up vaccination among migrants: a qualitative study and rapid review

Background

WHO’s Immunization Agenda 2030 has placed renewed focus on catch-up vaccination across the life course to meet global targets for reduction in vaccine-preventable diseases through increased vaccine coverage, including among migrant groups who may require catch-up vaccination to align them with host country vaccination schedules.

Methods

We did a global rapid review (01/2010 to 04/2022) to explore drivers of vaccine hesitancy among migrants followed by an in-depth qualitative study (semi-structured, telephone interviews) among recently arrived adult migrants (foreign-born, >18 years old, residing in the UK < 10 years). Interviews explored views on routine vaccination including accessibility, confidence and awareness. Data were analysed iteratively using thematic analysis.

Results

63 papers were included in the rapid review, including data from 22 countries/regions. Multiple factors driving under-immunisation and hesitancy in migrants were reported, including language barriers, low health literacy, social exclusion, low cultural competency and accessibility in healthcare systems. Our qualitative study recruited 40 migrants (mean age: 36.7 years; 62.5% female) resident in the UK (6 refugees, 19 asylum-seekers, 8 undocumented, 7 labour migrants). Major barriers to catch-up vaccination included a lack of provider recommendation and low awareness, with vaccination viewed as only relevant to children. Hesitancy around specific vaccines, such as MMR, was often influenced by misinformation. Participants suggested that novel strategies such as walk-in or mobile access points, consistent provider recommendations, and translation of information into relevant languages, may enhance accessibility and uptake of routine vaccinations.

Conclusions

Targeted and tailored information campaigns, versatile and proactive access pathways and education for healthcare staff on cultural competency will be needed to ensure uptake of catch-up vaccination among marginalised migrant groups.

Key messages

• Newly arrived adult migrants face barriers to catch-up vaccination in host countries, which may hinder immunisation coverage and increase the risk of vaccine-preventable disease outbreaks.

• Health systems must develop novel mechanisms to proactively offer culturally competent and accessible catch-up vaccination services to adult migrants on and after arrival.

Keratinocyte-associated protein 3 plays a role in body weight and adiposity with differential effects in males and females

Despite the obesity crisis in the United States, the underlying genetics are poorly understood. Our lab previously identified Keratinocyte-associated protein 3, Krtcap3, as a candidate gene for adiposity through a genome-wide association study in outbred rats, where increased liver expression of Krtcap3 correlated with decreased fat mass. Here we seek to confirm that Krtcap3 expression affects adiposity traits. To do so, we developed an in vivo whole-body Krtcap3 knock-out (KO) rat model. Wild-type (WT) and KO rats were placed onto a high-fat (HFD) or low-fat diet (LFD) at 6 weeks of age and were maintained on diet for 13 weeks, followed by assessments of metabolic health. We hypothesized that Krtcap3-KO rats will have increased adiposity and a worsened metabolic phenotype relative to WT. We found that KO male and female rats have significantly increased body weight versus WT, with the largest effect in females on a HFD. KO females also ate more and had greater adiposity, but were more insulin sensitive than WT regardless of diet condition. Although KO males weighed more than WT under both diet conditions, there were no differences in eating behavior or fat mass. Interestingly, KO males on a HFD were more insulin resistant than WT. This study confirms that Krtcap3 plays a role in body weight regulation and demonstrates genotype- and sex-specific effects on food intake, adiposity, and insulin sensitivity. Future studies will seek to better understand these sex differences, the role of diet, and establish a mechanism for Krtcap3 in obesity.

Analysing drivers of routine and COVID-19 vaccination in migrants to develop tailored interventions

Background

Migrants in Europe are at risk of under-immunisation and may also have lower COVID-19 vaccination intent and uptake. There is an urgent need to better understand the drivers of uptake in these groups to inform the development of migrant-sensitive interventions for COVID-19 vaccination and routine vaccination beyond the pandemic.

Methods

We did a systematic review (PROSPERO: CRD42020219214) following PRISMA guidelines to explore factors influencing vaccine uptake in migrants in the EU/EEA and identify determinants of under-immunisation. We also held 3 participatory workshops with multinational migrant community leaders (n = 23) in London, to explore solutions and approaches to strengthen COVID-19 vaccine roll-out.

Results

We included 66 papers reporting data on 262,761 migrants in the review. Numerous access-related factors (e.g. government policy, communication barriers) influenced uptake. Vaccine hesitancy was attributed to lack of information, concerns about side-effects, and cultural beliefs/stigma around specific vaccinations. Migrants who had recently arrived, were older, female or of African and Eastern Mediterranean origin were at risk for under-immunisation for key vaccine-preventable diseases. Migrant community leaders reported considerable hesitancy towards COVID-19 vaccination in their communities and misinformation circulating via social media. Leaders requested support in producing simple COVID-19 guidance that could be translated and adapted locally, alongside more meaningful engagement and partnership-working.

Conclusions

Access barriers and vaccine hesitancy may affect vaccine uptake in some migrant populations in Europe, which needs to be urgently addressed for COVID-19 vaccine roll-out but also beyond the pandemic to strengthen uptake of routine vaccinations. Actively involving migrant communities in the planning, co-production and implementation of tailored and targeted approaches will be essential.

On behalf of ESGITM.

Key messages

Access barriers and vaccine hesitancy (from information gaps, cultural factors) contribute to low vaccine uptake in some migrant populations in the EU/EEA, with implications for COVID-19 vaccination. Meaningful engagement and co-production of tailored approaches with under-immunised migrants are urgently needed to ensure their inclusion in COVID-19 and routine vaccination programmes.

Impact of COVID-19 on migrant populations in high-income countries: a systematic review

Background

Migrants in high-income countries (HICs) may have been disproportionately affected by the COVID-19 pandemic, yet the extent to which they are impacted, and their predisposing risk factors, are not clearly understood. We did a systematic review to assess clinical outcomes, indirect health and social impacts, and key risk factors in migrants.

Methods

Our systematic review following PRISMA guidelines (PROSPERO CRD42020222135) identified peer-reviewed and grey literature relating to migrants (foreign-born) and COVID-19 in 82 HICs. Primary outcomes were cases, hospitalisations and deaths from COVID-19 involving migrants; secondary outcomes were indirect health and social impacts and risk factors.

Results

3016 data sources were screened with 158 from 15 countries included in the analysis. We found migrants are at increased risk of SARS-CoV-2 infection and are over-represented among cases (e.g. constituting 42% of cases in Norway [to 27/4/2020], 26% in Denmark [to 7/9/2020], and 32% in Sweden [to 7/5/2020]); some datasets from Europe show migrants may be over-represented in deaths with increased all-cause mortality in migrants in some countries in 2020. Undocumented migrants, migrant health and care workers, and migrants housed in camps have been especially affected, with certain nationality groups disproportionately impacted. Migrants experience a range of risk factors for COVID-19, including high-risk occupations, overcrowded accommodation, and barriers to healthcare including inadequate information, language barriers, and reduced entitlement.

Conclusions

Migrants in HICs are at high risk of COVID-19, with a range of specific risk factors that have not been well-considered in the public health response to date. These data are of immediate relevance to the policy response to the pandemic, with strategies urgently needed to reduce transmission. Migrant populations must also be better considered in national plans for COVID-19 vaccination roll-out.

On behalf of ESGITM

Key messages

Migrants in high-income countries may be disproportionately represented in COVID-19 infections and deaths, with higher levels of many vulnerabilities and risk factors.

Migrants must be better included in all aspects of the pandemic response, including vaccination roll-out.

Digital screening tool (Health Catch-UP!) to promote multi-disease screening in migrants

Background

The ECDC has called for innovative strategies to deliver multi-disease screening (TB, LTBI, HIV, hepatitis B/C, Chagas, Strongyloidiasis and schistosomiasis) and catch-up vaccination (MMR, DTP) to adult migrants within the primary care context. We did a UK i qualitative study to explore current practice and seek views on a novel integrated digital tool to support delivery of screening recommendations for migrants https://emishealth.vids.io/videos/a49ad1bb1a18e4c72c/health-catch-up-with-requested-edits-mp4).

Methods

Phase 1 was conducted via telephone with clinical primary care practitioners (PCPs) (phase 1) and informed data collection and analysis for phase 2 with administrative staff. Data were analysed iteratively, informed by thematic analysis (Ethics no.20/HRA/1674).

Results

64 participants were recruited in Phase 1 (25 general practitioners [GPs], 15 nurses, 7 healthcare assistants, 1 pharmacist); Phase 2 comprised administrative staff (11 Practice-Managers, 5 receptionists). There was lack of consistency in delivery of screening and vaccination. Most GP practices adopted a practice-specific approach, or had no system in place; screening only for HIV and hepatitis B/C. Barriers to screening were perceived lack of knowledge/training and limited financial resources. Facilitators included having an infectious disease/migrant-health champion, incentivisation, and clear protocols. Participants responded positively to the integrated Health Catch-UP! tool, confirming that it would increase screening and vaccination, reduce missed opportunities for preventative healthcare, and raise awareness of migrant health.

Conclusions

Infectious disease screening and catch-up vaccination is not currently delivered well in primary care in high-migrant receiving European countries. Innovative digital tools like Health Catch-UP! could aid clinical decision-making and facilitating improved health outcomes for migrants. Further work is needed to evaluate this intervention.

Key messages

Infectious disease screening and catch-up vaccination is not currently delivered well in primary care in high-migrant receiving European countries. Innovative digital tools could aid clinical decision-making and facilitating improved health outcomes for migrants.

A systematic review of the association between mental health and tuberculosis disease risk

Background

Tuberculosis (TB) and mental illnesses are highly prevalent globally and often co-exist. Whilst poor mental health is known to modulate immune function, whether mental disorders causally increase TB incidence is unknown. This systematic review examines the association between mental health and TB disease risk to inform clinical and public health measures.

Methods

We carried out a systematic review following PRISMA guidelines (PROSPERO CRD42019158071). We searched MEDLINE, PsycINFO and PsycEXTRA databases alongside reference list and citation searching. Inclusion criteria were original research studies published 01/01/1970-11/05/2020 reporting data on the relationship between mental health and risk of TB disease. CASP and AXIS checklists were used to critically appraise included studies.

Results

We screened 1546 records published over 50 years, resulting in data synthesised from 607,184 individuals. Settings include Asia, South America, and Africa, and both mood (e.g. depression) and psychotic (e.g. schizophrenia) disorders are investigated. Robust evidence from cohort studies in Asia shows that depression and schizophrenia can increase risk of TB disease, with effect estimates ranging from HR = 1.15 [95% CI 1.03-1.28] to HR = 2.63 [95% CI 1.74-3.96] for depression and HR = 1.52 [95% CI 1.29-1.79] to RR = 3.04 for schizophrenia, and a dose-response relationship reported in one study. These data are consistent with data from cross-sectional studies, such as a large survey across low- and middle-income countries (n = 242,952) reporting OR = 3.36 [95% CI 3.01-4.50] for a depressive episode in those with TB versus those without.

Conclusions

Individuals with mental illnesses including depression and schizophrenia experience increased TB incidence and represent a high-risk population to target for screening and treatment. Integrated care for mental health and TB is needed, and interventions tackling mental illnesses and underlying drivers may help reduce TB incidence globally.

Key messages

This systematic review examines data from 607,184 individuals and finds evidence that mental health is a risk factor for TB disease. Those suffering from depression and schizophrenia are an at-risk population that could be identified and targeted for TB screening and treatment.

Meta-analysis of HIV-1 vaccine elicited mucosal antibodies in humans

We studied mucosal immune responses in six HIV-1 vaccine trials investigating different envelope (Env)-containing immunogens. Regimens were classified into four categories: DNA/vector, DNA/vector plus protein, protein alone, and vector alone. We measured HIV-1-specific IgG and IgA in secretions from cervical (n = 111) and rectal swabs (n = 154), saliva (n = 141), and seminal plasma (n = 124) and compared to corresponding blood levels. Protein-containing regimens had up to 100% response rates and the highest Env-specific IgG response rates. DNA/vector groups elicited mucosal Env-specific IgG response rates of up to 67% that varied across specimen types. Little to no mucosal IgA responses were observed. Overall, gp41- and gp140-specific antibodies dominated gp120 mucosal responses. In one trial, prior vaccination with a protein-containing immunogen maintained durability of cervical and rectal IgG for up to 17 years. Mucosal IgG responses were boosted after revaccination. These findings highlight a role for protein immunization in eliciting HIV-1-specific mucosal antibodies and the ability of HIV-1 vaccines to elicit durable HIV-1-specific mucosal IgG.

Early life stress induces hyperactivity but not increased anxiety-like behavior or ethanol drinking in outbred heterogeneous stock rats

Early life stress is known to impact vulnerability to psychopathological disorders in adulthood, including anxiety and alcohol use disorder (AUD), but the mechanisms underlying susceptibility to these outcomes are not fully understood. In the current study, we used adolescent social isolation (ASI) to determine whether Heterogeneous Stock (HS) rats, an outbred model used for genetic fine-mapping, could be used to study the genetics contributing to ASI-induced anxiety- and AUD-like behavior. We isolated (ASI) or group-housed (adolescent group-housed; AGH) 64 male HS rats at 4 weeks of age. After 5 weeks in these housing conditions, multiple anxiety and coping/despair-like behaviors were measured. All rats were then individually housed and assessed for voluntary ethanol self-administration. At euthanasia, synaptoneurosomes were isolated from a subset of brains to examine the expression of two proteins associated with alcohol drinking-related behaviors, GluA1 and SK2, in the dorsal (dHC) and ventral hippocampus (vHC). We found that ASI increased hyperactivity in the open field test relative to AGH, with no changes in other anxiety-like behaviors. Surprisingly, ASI rats demonstrated decreased immobility and increased climbing in the forced swim test relative to AGH. In contrast to prior studies by us and others, we found no difference in self-administration of 20% ethanol, with decreased ethanol self-administration in ASI relative to AGH rats at higher ethanol concentrations. Furthermore, while ASI in Long-Evans rats resulted in decreased SK2 expression in vHC synaptosomes, no differences were seen in vHC synaptosomes for SK2 or GluA1 in HS rats. These results demonstrate that HS rats are protected against many of the negative effects previously seen in response to ASI, namely anxiety-like behavior and increased ethanol self-administration. The current work suggests that a lack of change in SK2 and GluA1 expression levels in the vHC may play a role in conferring this protection.

Migration and outbreaks of vaccine-preventable disease in Europe: a systematic analysis (1990-2019)

Background

Migrant populations (defined as foreign-born) in the EU/EEA may be one of several under-immunised populations yet their role in outbreaks of vaccine-preventable diseases (VPDs) has been poorly defined to date.

Methods

We did both a temporal analysis to map published reports of migrant-related outbreaks against data from the ECDC's Surveillance Atlas of Infectious Disease, and a systematic review (PROSPERO CRD42019157473; 1990-2019) adhering to PRISMA guidelines, to explore whether migrants are involved in outbreaks in Europe and which particular subpopulations may be at increased risk. Studies on VPD outbreaks (measles, mumps, rubella, diphtheria, pertussis, polio, hepatitis A, N meningitidis, and H influenzae) in migrants residing in the EU/EEA were included.

Results

46 studies were included, reporting on 50 VPD outbreaks across 13 EU/EEA countries, of which 98% (n = 49) occured since January 2000. Measles had the highest number of reports of outbreaks involving migrants (n = 21; 5043 cases), followed by varicella (n = 10; 595 cases) and hepatitis A (n = 10; 1226 cases). 21 (40%) of outbreaks were reported from shelters for asylum seekers and refugees (mainly varicella or measles). Of 27 outbreaks where the index case was defined, 20 (74.1%) were migrants, including 9 (33.3%) from Eastern Europe and 6 (22.2%) from Africa. When mapped against the ECDC timeline of measles outbreaks, migrant-related outbreaks coincide with Europe-wide peaks in measles incidence (in 2006, 2010, and 2018).

Conclusions

Migrants represent one key group involved in VPD outbreaks, with refugees/asylum seekers residing in shelters or camps particularly at risk. Measles accounted for 38% of all reported outbreaks. Improved data collection on migrant status across Europe is crucial to understanding the complex relationship between migration and occurrence of VPD outbreaks to inform policy decisions on the most effective strategies to prevent future outbreaks.

Key messages

Migrants represent one key group involved in vaccine-preventable diseases outbreaks in Europe. Refugees and asylum seekers may be particularly at risk.

Reducing Cancer-related Financial Toxicity through Financial Navigation: Results from a Pilot Intervention

Our purpose was to pilot a novel patient-centered financial navigation (FN) intervention to decrease the burden of financial toxicity (FT) among uninsured and underinsured patients with cancer treated at the North Carolina Cancer Hospital (NCCH). Methods: Participants were recruited by cancer clinic nurses and social workers at the NCCH. Eligible patients scored less than 22 points (indicating significant FT) on the COmprehensive Score for financial Toxicity (COST) instrument. Fifty patients were enrolled in the intervention, which included an intake assessment of financial needs and vulnerability, initial one-on-one consultation with a trained financial navigator (i.e., financial counselor or social worker), triage to financial support services matching patients' needs, and multiple follow-up appointments. Navigator recommendations were based upon a detailed review of patients' financial status, billing information, insurance, and other indicators used to refer patients to appropriate financial and social services resources offered by the hospital, government, nonprofits and private corporations. Following the initial appointment, patients were given a checklist of resources they were eligible for and the required paperwork to complete applications. During follow-up appointments, application status was reviewed, and practical assistance was provided. Patients were re-contacted at 2-week intervals to assess progress toward financial assistance goals. Outcome data collection included pre/post-intervention COST scores, patient satisfaction with the intervention, and intervention fidelity and retention. Results: The first fifty patients approached all screened positive for FT (COST < 22). Baseline COST scores ranged from 0–19. Results indicated a significant improvement in COST scores following the FN intervention (average increase = 6.86, 95% CI = 4.30–9.42), P < 0.0001). Post-intervention questionnaires indicated excellent patient satisfaction and retention with the FN intervention, and navigator logs indicated high fidelity to the intervention protocol. Conclusions: A novel FN intervention was feasible, acceptable, and effective in reducing FT among uninsured and underinsured oncology patients.

Modification of the Association Between T-Cell Immune Responses and Human Immunodeficiency Virus Type 1 Infection Risk by Vaccine-Induced Antibody Responses in the HVTN 505 Trial

Background

HVTN 505 was a human immunodeficiency virus type 1 (HIV-1) preventive vaccine efficacy trial of a DNA/recombinant adenovirus serotype 5 (rAd5) vaccine regimen. We assessed antibody responses measured 1 month after final vaccination (month 7) as correlates of HIV-1 acquisition risk.

Methods

Binding antibody responses were quantified in serum samples from 25 primary endpoint vaccine cases (diagnosed with HIV-1 infection between month 7 and month 24) and 125 randomly sampled frequency-matched vaccine controls (HIV-1 negative at month 24). We prespecified for a primary analysis tier 6 antibody response biomarkers that measure immunoglobulin G (IgG) and immunoglobulin A (IgA) binding to Env proteins and 2 previously assessed T-cell response biomarkers.

Results

Envelope-specific IgG responses were significantly correlated with decreased HIV-1 risk. Moreover, the interaction of IgG responses and Env-specific CD8+ T-cell polyfunctionality score had a highly significant association with HIV-1 risk after adjustment for multiple comparisons.

Conclusions

Vaccinees with higher levels of Env IgG have significantly decreased HIV-1 risk when CD8+ T-cell responses are low. Moreover, vaccinees with high CD8+ T-cell responses generally have low risk, and those with low CD8+ T-cell and low Env antibody responses have high risk. These findings suggest the critical importance of inducing a robust IgG Env response when the CD8+ T-cell response is low.

Genetic Fine-Mapping and Identification of Candidate Genes and Variants for Adiposity Traits in Outbred Rats

OBJECTIVE

Obesity is a major risk factor for multiple diseases and is in part heritable, yet the majority of causative genetic variants that drive excessive adiposity remain unknown. Here, outbred heterogeneous stock (HS) rats were used in controlled environmental conditions to fine-map novel genetic modifiers of adiposity.

METHODS

Body weight and visceral fat pad weights were measured in male HS rats that were also genotyped genome-wide. Quantitative trait loci (QTL) were identified by genome-wide association of imputed single-nucleotide polymorphism (SNP) genotypes using a linear mixed effect model that accounts for unequal relatedness between the HS rats. Candidate genes were assessed by protein modeling and mediation analysis of expression for coding and noncoding variants, respectively.

RESULTS

HS rats exhibited large variation in adiposity traits, which were highly heritable and correlated with metabolic health. Fine-mapping of fat pad weight and body weight revealed three QTL and prioritized five candidate genes. Fat pad weight was associated with missense SNPs in Adcy3 and Prlhr and altered expression of Krtcap3 and Slc30a3, whereas Grid2 was identified as a candidate within the body weight locus.

CONCLUSIONS

These data demonstrate the power of HS rats for identification of known and novel heritable mediators of obesity traits.

Safety, pharmacokinetics, and immunological activities of multiple intravenous or subcutaneous doses of an anti-HIV monoclonal antibody, VRC01, administered to HIV-uninfected adults: Results of a phase 1 randomized trial

BACKGROUND

VRC01 is an HIV-1 CD4 binding site broadly neutralizing antibody (bnAb) that is active against a broad range of HIV-1 primary isolates in vitro and protects against simian-human immunodeficiency virus (SHIV) when delivered parenterally to nonhuman primates. It has been shown to be safe and well tolerated after short-term administration in humans; however, its clinical and functional activity after longer-term administration has not been previously assessed.

METHODS AND FINDINGS

HIV Vaccine Trials Network (HVTN) 104 was designed to evaluate the safety and tolerability of multiple doses of VRC01 administered either subcutaneously or by intravenous (IV) infusion and to assess the pharmacokinetics and in vitro immunologic activity of the different dosing regimens. Additionally, this study aimed to assess the effect that the human body has on the functional activities of VRC01 as measured by several in vitro assays. Eighty-eight healthy, HIV-uninfected, low-risk participants were enrolled in 6 United States clinical research sites affiliated with the HVTN between September 9, 2014, and July 15, 2015. The median age of enrollees was 27 years (range, 18-50); 52% were White (non-Hispanic), 25% identified as Black (non-Hispanic), 11% were Hispanic, and 11% were non-Hispanic people of diverse origins. Participants were randomized to receive the following: a 40 mg/kg IV VRC01 loading dose followed by five 20 mg/kg IV VRC01 doses every 4 weeks (treatment group 1 [T1], n = 20); eleven 5 mg/kg subcutaneous (SC) VRC01 (treatment group 3 [T3], n = 20); placebo (placebo group 3 [P3], n = 4) doses every 2 weeks; or three 40 mg/kg IV VRC01 doses every 8 weeks (treatment group 2 [T2], n = 20). Treatment groups T4 and T5 (n = 12 each) received three 10 or 30 mg/kg IV VRC01 doses every 8 weeks, respectively. Participants were followed for 32 weeks after their first VRC01 administration and received a total of 249 IV infusions and 208 SC injections, with no serious adverse events, dose-limiting toxicities, nor evidence for anti-VRC01 antibodies observed. Serum VRC01 levels were detected through 12 weeks after final administration in all participants who received all scheduled doses. Mean peak serum VRC01 levels of 1,177 μg/ml (95% CI: 1,033, 1,340) and 420 μg/ml (95% CI: 356, 494) were achieved 1 hour after the IV infusion series of 30 mg/kg and 10 mg/kg doses, respectively. Mean trough levels at week 24 in the IV infusion series of 30 mg/kg and 10 mg/kg doses, respectively, were 16 μg/ml (95% CI: 10, 27) and 6 μg/ml (95% CI: 5, 9) levels, which neutralize a majority of circulating strains in vitro (50% inhibitory concentration [IC50] > 5 μg/ml). Post-infusion/injection serum VRC01 retained expected functional activity (virus neutralization, antibody-dependent cellular cytotoxicity, phagocytosis, and virion capture). The limitations of this study include the relatively small sample size of each VRC01 administration regimen and missing data from participants who were unable to complete all study visits.

CONCLUSIONS

VRC01 administered as either an IV infusion (10-40 mg/kg) given monthly or bimonthly, or as an SC injection (5 mg/kg) every 2 weeks, was found to be safe and well tolerated. In addition to maintaining drug concentrations consistent with neutralization of the majority of tested HIV strains, VRC01 concentrations from participants' sera were found to avidly capture HIV virions and to mediate antibody-dependent cellular phagocytosis, suggesting a range of anti-HIV immunological activities, warranting further clinical trials.

TRIAL REGISTRATION

Clinical Trials Registration: NCT02165267.

Distinct genital tract HIV-specific antibody profiles associated with tenofovir gel

The impact of topical antiretrovirals for pre-exposure prophylaxis on humoral responses following HIV infection is unknown. Using a binding antibody multiplex assay, we investigated HIV-specific IgG and IgA responses to envelope glycoproteins, p24 Gag and p66, in the genital tract (GT) and plasma following HIV acquisition in women assigned to tenofovir gel (n=24) and placebo gel (n=24) in the CAPRISA 004 microbicide trial to assess if this topical antiretroviral had an impact on mucosal and systemic antibody responses. Linear mixed effect modeling and partial least squares discriminant analysis was used to identify multivariate antibody signatures associated with tenofovir use. There were significantly higher response rates to gp120 Env (P=0.03), p24 (P=0.002), and p66 (P=0.009) in plasma and GT in women assigned to tenofovir than placebo gel at multiple time points post infection. Notably, p66 IgA titers in the GT and plasma were significantly higher in the tenofovir compared with the placebo arm (P<0.05). Plasma titers for 9 of the 10 HIV-IgG specificities predicted GT levels. Taken together, these data suggest that humoral immune responses are increased in blood and GT of individuals who acquire HIV infection in the presence of tenofovir gel.

Abstract PD6-07: Genomic sequencing in metastatic breast cancer patients to inform clinical practice at the University of North Carolina at Chapel Hill

Background: An increasing number of molecularly-targeted therapies for metastatic breast cancer (MBC) are clinically-available (approved and investigational). These anti-cancer agents target specific molecular abnormalities such as mutated, amplified, deleted, or rearranged genes. Reporting of unique tumor genetic alterations is not included in routine clinical/diagnostic panels. In MBC, knowledge of mutational status may foster efficient transitions in clinical care and trial enrollment at disease progression. We describe the development and implementation of a clinically-integrated genomic sequencing program and report how information regarding targetable genomic aberrations in MBC patients (pts) is used to improve clinical practice in an academic setting.

Methods: Genomic sequencing of investigative biomarkers was prospectively offered to pts with MBC. DNA libraries were prepared separately from a retrieved archival FFPE tumor sample and a matched normal sample from each pt. Relevant targets were enriched by custom Agilent SureSelect hybrid capture baits using standard protocols. Samples were sequenced on Illumina HiSeq 2000/2500 platforms. Mutational findings were reviewed by a molecular tumor board (MTB); variants identified to be potentially actionable underwent confirmatory testing in a CLIA-approved laboratory. Confirmed findings were inserted into the pt's EMR accessible by both the pt and the treating oncologist.

Results: Of the 725 MBC pts seen at UNC since 1/1/2012, 194 (27%) contributed samples for genomic sequencing. Of those whose tumors were sequenced, average age at MBC diagnosis was 54 (25 - 91); 73% were Caucasian, 16% African American. De novo MBC accounted for 39 (20%) sequenced pts. Of sequenced patients, sites of metastatic disease included bone only (7%), visceral only (46%), and both bone and visceral (47%). Approximately 1/3 of pts were consented for sequencing at time of initial MBC diagnosis, 1/4 after 1st line therapy for MBC, and the remaining at or beyond their 2nd line. In total, 131 (68%) pts have sequencing results available of which 43% of pts had reportable mutations deemed actionable by the MTB. Specific mutations and observed frequency by subtype are shown below. Pts (19%) whose tumors were sequenced were more commonly enrolled in a therapeutic clinical trial for MBC, a higher rate than seen in the non-sequenced group (7%) (p&lt;0.001). To date, 27% of pts' tumors harbored an alteration that is an eligibility requirement for a molecularly-targeted therapeutic trial accruing pts at UNC.

Observed Mutation by Clinical Subype Genes Total # (56 pts)HR+/HER2- (25 pts)HER2+ (13 pts)TNBC (18pts)PIK3CA15933TP5315456CCND19531NF-14103FGFR13300PTEN3012KRAS2011MDM22110PIK3R12002ROS12011TSC12011Other*14518TOTAL73281728*Mutations observed only once

Conclusion: Preemptive genomic sequencing can be integrated into the clinical and operational practice of a comprehensive cancer center. Currently this research tool and program provides valuable information that has the potential to foster both clinical trial eligibility and/or enrollment. With longer follow-up, we hope such an approach ultimately will improve patient outcomes.

Citation Format: Grilley-Olsen J, Keith KC, Hayward M, Dees EC, Deal A, Ivanova A, Benbow JM, Parker J, Patel NM, Eberhard D, Mieczkowski P, Weck KE, Hayes DN, Muss H, Jolly T, Reeder-Hayes K, Earp HS, Sharpless N, Carey L, Anders CK. Genomic sequencing in metastatic breast cancer patients to inform clinical practice at the University of North Carolina at Chapel Hill. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr PD6-07.

Abstract P5-12-06: Comprehensive assessment of the effect of genetic polymorphisms in drug metabolizing enzymes and transporters on tamoxifen activation to endoxifen

Background: Tamoxifen is the most commonly prescribed hormonal drug for estrogen receptor positive breast cancer treatment. Tamoxifen itself has weak anti-estrogenic activity, but is bioactivated to the more potent inhibitor endoxifen. Recent data suggest inferior efficacy of tamoxifen treatment in patients who have low systemic endoxifen concentration. Genetic variability in drug metabolizing enzymes and transporters, particularly CYP2D6, are known to effect serum endoxifen concentration. The association of CYP2D6 genotype and endoxifen concentration is well established; however, there is a paucity of data regarding the effects of genetic variants in other drug metabolizing enzymes and transporters on endoxifen concentrations. The objective of our study was to comprehensively screen known, functionally consequential polymorphisms and copy number variations in genes of interest to detect additional pharmacogenetic predictors of endoxifen concentration during tamoxifen treatment.

Methods: This analysis includes patients prospectively enrolled on the Lineberger Comprehensive Cancer Center 0801 trial. Patients had received tamoxifen for a minimum of 4 months prior to enrollment and were not concurrently taking strong or moderate CYP2D6 inhibitors. Samples were collected at enrollment for measurement of steady state endoxifen level and collection of germline DNA. Genotyping was performed for CYP2D6 using the Amplichip® CYP450 test (Roche Diagnostics) and for other candidate genes (CYP2C9, CYP3A4, CYP3A5, ABCB1, SLCO1B1, SULT1A1, SULT1A2, and UGT2B7) using the iPLEX® ADME PGx Pro Panel (Agena Bioscience). Activity phenotype for each gene was inferred from genotype data based on known activity of variant alleles or copy numbers. Metabolite concentrations were measured via LC/MS-MS assay at Indiana University and square root transformed prior to analysis to improve normality. Linear regression models were used to evaluate the association of each gene individually with endoxifen concentration, assuming an additive pharmacogenetic effect, after adjustment for CYP2D6 phenotype (EM/UM, IM or PM).

Results: 304 Patients with steady-state endoxifen concentration and successful genotyping were included in the analysis. After transformation and adjustment, endoxifen concentration was significantly associated with carrying low-activity CYP2C9 variant alleles (*2, *3, *5, *6, *8, *11, *12) (p=0.016). Predicted endoxifen concentration based on CYP2C9 and CYP2D6 genotype can be found in.

Predicted endoxifen concentration (ng/mL) based on CYP2C9 and CYP2D6 Phenotype CYP2D6 EM/UMCYP2D6 IMCYP2D6 PMCYP2C9 WT/WT9.716.553.41CYP2C9 WT/Var8.375.482.63CYP2C9 Var/Var7.134.481.96Abbreviations: WT= wild-type, Var=Variant allele for CYP2C9

Phenotype activity of other enzymes and transporters was not associated with endoxifen concentration (all p&gt;0.05).

Conclusions: Polymorphisms in CYP2C9 and CYP2D6, but not other enzymes or transporters, contribute to variation in endoxifen exposure. If endoxifen exposure is validated to predict tamoxifen efficacy, personalized tamoxifen dosing algorithms should include CYP2C9, in addition to CYP2D6 and clinical factors, to improve efficacy and minimize side effects.

Citation Format: Hertz DL, Danko W, Deal A, Walko CM, Flockhart DA, McLeod HL, Ibrahim JG, Irvin Jr WJ. Comprehensive assessment of the effect of genetic polymorphisms in drug metabolizing enzymes and transporters on tamoxifen activation to endoxifen. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-12-06.

Abstract P6-11-06: Efficacy of carboplatin alone or with ABT888 in an intracranial murine model of BRCA-mutated, basal-like, triple negative breast cancer (TNBC)

Background: TNBC frequently spreads to the central nervous system and is associated with poor outcome. Twenty percent of women with TNBC harbor a BRCA mutation(mut). BRCA dysfunction impairs repair of DNA double-strand breaks by homologous recombination(HR) and sensitizes tumor cells to DNA-damaging cytotoxic agents. Emerging evidence suggests that TNBC responds to platinums(Pt) and drugs potentiating efficiency of DNA damage, such as PARP inhibitors; combination therapy may enhance DNA damage and induce additional cytotoxicity. Recognizing that Pt and many PARP inhibitors penetrate the blood brain barrier(BBB), we evaluated the efficacy of carboplatin(Carbo) alone and with the PARP inhibitor, ABT888(ABT), in murine intracranial(IC) TNBC models characterized by BRCA status.

Methods: Athymic (nu/nu) mice(10wks) were inoculated intracerebrally with 2×105 SUM149(BRCA1mut, pTEN-; basal) cells expressing luciferase. On day14, tumor-bearing mice began treatment with Control(PBS IP weekly), Carbo(50mg/kg IP weekly) and ABT(25mg/kg OG daily) as single agents, or in combination. Survival and IC tumor growth via bioluminescence were compared by treatment. Net PAR levels(PARpg/ml/100ug total protein) were measured in IC tumor tissue(ELISA pharmacodynamic assay) 14days post ABT. Presence of Pt DNA adducts was measured in IC tumor tissue following Carbo+/-ABT by ICP-MS. Survival and IC tumor growth via bioluminescence of the MDA-MB468(BRCAnon-mut, pTEN-; basal) IC model treated with the same regimens were assessed.

Results: In the SUM149 TNBC IC model, Carbo+/-ABT resulted in improved survival compared to control (Table). Single agent ABT did not yield a survival benefit over control. Combination Carbo/ABT showed a modest advantage in survival compared to Carbo alone (p = 0.28). IC tumor mean net PAR levels ± SEM were significantly lower in ABT-treated animals compared to control (182.1 ± 91.3 vs 825.7 ± 174.7, p = 0.0043). Addition of ABT did not impair Carbo BBB penetration; Mean ± SEM Pt-DNA adducts were detected in IC tumor after administration of Carbo and Carbo/ABT (0.91±0.13 and 1.46±0.03 pgPt/ugDNA). In contrast to the SUM149 IC model, there was no survival improvement for the MDA-MB468 IC model treated with Carbo+/-ABT compared to control(p = 0.81).

 SUM149(BRCA1mut)MDA-MB468(BRCA1non-mut)TreatmentNMedian Survival (95%CI), dayspValueNMedian Survival (95%CI), daysControl1736(34-40)N/A535(29-57)ABT1039(30-46)p = 0.22544(33-57)Carbo1658(47-67)p&lt;.0001537(33-54)Carbo/ABT1764(59-75)p&lt;.0001537(33-50)

Conclusions: This study shows Pt analogues, specifically Carbo, represent a promising treatment strategy for TNBC brain metastases with BRCA dysfunction. Improved survival relies on the ability of Pt analogues to penetrate the BBB and higher cytotoxicity may be due to compromised HR in TNBC as compared to models with functional BRCA. Although inhibitory activity of ABT was detected in IC tumors, we did not observe a significant additive effect of ABT to Carbo when used in combination. Confirmatory studies in additional IC TNBC models, including claudin-low subtype, as well as mechanistic studies evaluating DNA damage via γH2AX foci and differential gene expression in response to treatment are ongoing.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-11-06.

P2-16-02: How Well Do Medical Oncologists and Plastic Surgeons Communicate about Their Patients?

Background: While complications of post-mastectomy breast reconstruction can affect the timing of adjuvant chemotherapy, chemotherapy can affect the wound healing process after reconstruction. Due to this interdependence, adequate communication between medical oncologists (MO) and plastic surgeons (PS) may be critical to optimize patient outcomes. In this study, we sought to evaluate the knowledge MO and PS have of each other's fields, the roles they expect of each other, and how often they communicate in treating breast reconstruction patients.

Methods: A cross-sectional survey was conducted in a convenience sample of MO who treat at least one breast cancer (BC) patient per month and PS who perform at least one breast reconstruction per year. Surveys were distributed via email, US mail, and at two professional meetings. The survey included knowledge questions about reconstruction and chemotherapy, questions about provider and patient responsibilities for timely chemotherapy initiation, and questions about communication with other specialties. Fisher's Exact and Wilcoxon Rank Sum tests were used to compare differences between groups.

Results: 53 medical oncologists and 23 plastic surgeons completed surveys (51% response rate). MO and PS had similar overall knowledge scores (MO 59%, PS 56%, p=0.5). 23% of MO knew the correct treatments for breast skin necrosis, and 60% knew the correct treatment for seromas. 32% of PS knew the approximate duration of Her2-directed therapy, and 14% of PS identified the usual adjuvant treatment for patients who have had neoadjuvant chemotherapy. Providers from both specialties who primarily practice in a rural setting scored significantly lower on the knowledge portion of the survey than those practicing in an academic medical center or urban/suburban area (51% rural versus 59%, p=0.03).

The MO and PS agreed on the MO's degree of responsibility for timely chemotherapy initiation (MO mean 4.6 versus PS mean 4.4 out of 5, p =0.2). However, they disagreed about the PS's responsibility for timely chemotherapy initiation (MO mean 3.8, PS mean 3.0 out of 5, p=0.01).

MO attributed low importance to a history of immediate breast reconstruction when planning chemotherapy treatment (mean 2.5 out of 10). PS placed little importance on the likelihood of post-operative chemotherapy when planning immediate breast reconstruction (mean 3.6 out of 10). Both MO and PS reported more frequent communication with each other about patients with complications than about uncomplicated patients (mean 3.9 times over first 6 month for complications versus mean 1.6 over first 6 months for uncomplicated). This translated to communicating about 2.5 times as often for complicated patients (p&lt;0.001).

Conclusion: Medical oncologists and plastic surgeons have substantial deficits in knowledge about each other's fields and differ in their opinion regarding the burden of responsibility in ensuring timely chemotherapy initiation. While MO and PS increase their communication when complications arise, these data suggest room for improvement in communication and understanding, which could improve the care of BC patients who undergo reconstruction and chemotherapy.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-16-02.

Hematologic toxicities before and during bevacizumab chemotherapy in women with gynecologic malignancy

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Background: Many women undergoing chemotherapy for gynecologic malignancy experience hematologic toxicity that delays therapy or requires supportive intervention. In animal models anti-VEGF antibodies increase erythropoietin levels. We examined the hematologic toxicities experienced by patients prior to (PR) and during bevacizumab (BR) treatment. Methods: Retrospective, single-institution study of women with gynecologic malignancy treated at the University of North Carolina with bevacizumab as part of their therapy from January 2005 to June 2007. Data collected included prior therapies, blood product and growth factor use, and interruptions in therapy. Comparisons were made between individual patients’ hematologic parameters during the PR and BR. Median differences between hematologic nadirs were compared using Wilcoxon Signed Rank Tests. Differences in proportions were compared by Chi-Square or Fisher's Exact tests. Results: 43 patients ware identified, 40 with complete data. Most women were Caucasian (88%) and had ovarian or primary peritoneal carcinoma (77%); median (range) age was 53 (23–73). 32 (74%) received three or more different chemotherapy drugs before starting bevacizumab. The median difference in HCT nadir (31.2 vs. 33, p = 0.01) and ANC nadir (1.2 vs. 1.4, p = 0.04) during the PR and BR were significant in favor of the bevacizumab regimens. The median nadir differences for WBC (2.7 vs. 3.1, p = 0.1) and PLT (129 vs. 150, p = 0.07) were non-significant favoring BR. For HCT toxicity grades, 22 (55%) had the same grade during their PR and BR, 15 (38%) had a lower grade during BR, and 3 (7%) had a higher grade during BR (p = 0.001). Similar trends were seen for WBC (p = 0.27), ANC (p = 0.1), and PLT (p = 0.15). During BR there was a trend toward fewer patients receiving darbepoetin (66% vs. 44%, p = 0.07) and filgastrim (29% vs. 14%, p = 0.1). Conclusions: Patients receiving bevacizumab had no worse hematologic toxicity compared to their prior regimens and may have had less severe anemia. While not statistically significant, there were trends toward less growth factor use with bevacizumab. Patients who have had prior hematologic toxicity should be considered for bevacizumab. The effect of bevacizumab on hematologic toxicity should be evaluated with prospective data.

No significant financial relationships to disclose.

The expression of fetuin in the development and maturation of the hemopoietic and immune systems

The distribution and expression of fetuin, a fetal plasma protein that has been shown to have a wide-spread intracellular presence in many developing tissues including the central nervous system, has been studied in the developing immune and hemopoietic organs of fetal and adult sheep. The presence of fetuin was demonstrated using immuno-cytochemistry and expression of fetuin was studied using northern blot analysis and in situ hybridization. In the developing sheep fetus, fetuin was shown to be expressed first in the hemopoietic cells of the fetal liver and subsequently in the forming spleen. The very first stromal, bone marrow-forming cells, also expressed fetuin mRNA. These cells became more numerous during gestation and by embryonic day (E)115 (term is 150 days), fetuin-expressing cells were identified morphologically to be monocytes/macrophages. Fetuin protein, on the other hand, was present in all hemopoietic and immune organs from the earliest age studied (E30) but was confined initially to matrix, mesenchymal tissue. Fetuin-positive cells could be identified in the spleen at E60 as early hemopoietic cells, in the lymph nodes at E60 as stromal cells and macrophages, and at E115 in the thymus as macrophages and squamous cells. In the adult, fetuin mRNA was only detectable by northern blot in the liver and the bone marrow. Using in situ hybridization in adult tissue, fetuin mRNA-positive cells were identified in the bone marrow to be monocytes/macrophages. Additionally, in the spleen germinal centres, fetuin mRNA was identified in cells with the morphology of dendritic cells. Using three separate cellular markers: lysozyme, S-100, and alpha 1-antitrypsin, the cellular identification of fetuin-positive cells was confirmed to be in the monocyte/macrophage lineage.

Repair and recovery following spinal cord injury in a neonatal marsupial (Monodelphis domestica)

1. Repair and recovery following spinal cord injury (complete spinal cord crush) has been studied in vitro in neonatal opossum (Monodelphis domestica), fetal rat and in vivo in neonatal opossum. 2. Crush injury of the cultured spinal cord of isolated entire central nervous system (CNS) of neonatal opossum (P4-10) or fetal rats (E15-E16) was followed by profuse growth of fibres and recovery of conduction of impulses through the crush. Previous studies of injured immature mammalian spinal cord have described fibre growth occurring only around the lesion, unless implanted with fetal CNS. 3. The period during which successful growth occurred in response to a crush is developmentally regulated. No such growth was obtained after P12 in spinal cords crushed in vitro at the level of C7-8. 4. In vivo, in the neonatal (P4-8) marsupial opossum, growth of fibres through, and restoration of, impulse conduction across the crush was apparent 1-2 weeks after injury. With longer periods of time after crushing a considerable degree of normal locomotor function developed. 5. By the time the operated animals reached adulthood, the morphological structure of the spinal cord, both in the region of the crush and on either side of the site of the lesion, appeared grossly normal. 6. The results are discussed in relation to the eventual longterm possibility of devising effective treatments for patients with spinal cord injuries.

Expression and distribution of fetuin in the developing sheep fetus

Tissue distribution and developmental expression of fetuin were studied in the sheep fetus from embryonic day (E) 30 to adult (gestational period is 150 days). The presence of fetuin was demonstrated immunocytochemically using anti-fetuin antibodies; in situ hybridisation using short anti-sense oligonucleotide probes labelled with digoxigenin was used to study the ability of the developing tissue to synthesise fetuin, and reverse transcription-polymerase chain reaction (RT-PCR) was used to estimate the level of fetuin mRNA in selected tissues. Tissue distribution of fetuin was widespread in the younger fetuses (E30 to E40). The most prominent presence due to in situ synthesis was demonstrated in the liver, central nervous system (CNS) including anterior horn cells, dorsal root ganglia and in skeletal muscle cells. Other developing tissues and organs that showed evidence of fetuin synthesis and presence of the protein included mesenchyme, kidney, adrenal, developing bone, gut, lung and heart. In the immature liver (E30-40) there was a strong signal for fetuin mRNA in hepatocytes and also in numerous haemopoietic cells; the proportion of these latter cells that was positive for fetuin mRNA increased between E30 and E40. Only some hepatocytes and a proportion of the haemopoietic stem cells were immunoreactive for fetuin itself at E30-40; immunoreactive hepatocytes were more frequently observed in the more mature outer regions of the developing liver. Lung and gut contained scattered fetuin-positive epithelial cells, especially at E30; a weak fetuin mRNA signal could be detected above background in many of these cells up to E40, but not at E60-E115 or in the adult. Particularly at E30 to E40, mesenchymal tissue both within organs such as the gut and lung and around forming bone and skeletal muscle contained cells that were positive for fetuin mRNA. Mesenchyme at these ages was also very strongly stained for fetuin protein, much of which may reflect fetuin in tissue extracellular spaces and be derived from the high concentration in plasma. By E80 fetuin mRNA was mainly present in the liver and the CNS; staining of the muscle tissue was becoming less pronounced. However in developing bone tissue, staining of chondrocytes for fetuin mRNA was still prominent in older (E80) fetuses; there was also fetuin protein staining of chondrocytes at the growing surfaces of bones and in bone marrow at this age. In the adult, weak immunocytochemical staining for fetuin itself was present in hepatocytes, but the mRNA signal was barely above the threshold limit of detection.(ABSTRACT TRUNCATED AT 400 WORDS)