Characterising B cell expression and prognostic significance in human papillomavirus positive oropharyngeal cancer

OBJECTIVES

The incidence of human papillomavirus positive oropharyngeal cancer (HPV+OPC) is increasing, and new biomarkers are required to better define prognostic groups and guide treatment. Infiltrating T cells have been well studied in head and neck cancer, however the presence and role of B cells and tertiary lymphoid structures (TLS) in the tumor microenvironment has not, even though the interplay between T and B cells is increasingly being recognised.

MATERIALS AND METHODS

Using CD20 immunohistochemistry (IHC) to identify B cells and TLS in a cohort of 159 HPV + OPC patients, we semi-quantitatively scored abundance and location (intra-tumoral or stromal) and correlated findings with patient survival.

RESULTS

32% (51/157) of patients had high intra-tumoral (IT) abundance of CD20+ B cells (≥5%) and this was prognostic for improved overall survival (OS) with an adjusted hazard ratio (HR) of 0.2 (95 % CI 0.0-0.7, p = 0.014). We validated our results in an independent cohort comprising 171 HPV + OPC where 14% (23/171) were IT CD20+ high, again showing improved survival with an adjusted HR for OS of 0.2 (95 % CI 0.0-1.4, p = 0.003). Neither stromal abundance nor the presence of TLS were prognostic in either cohort. B cells were subtyped by multispectral IHC, identifying CD20+CD27+ cells, consistent with memory B cells, as the predominant subtype. Combined with validated biomarker CD103, a marker of tissue-resident memory T cells, IT CD20+ B cells abundance was able to prognostically stratify patients further.

CONCLUSIONS

CD20+ B cell abundance has the potential to be used as a biomarker to identify good and poor prognosis HPV + OPC patients.

Neuregulin-1 (NRG1) polymorphisms linked with psychosis transition are associated with enlarged lateral ventricles and white matter disruption in schizophrenia

BACKGROUND

Two single-nucleotide polymorphisms (SNPs) (rs4281084 and rs12155594) within the neuregulin-1 (NRG1) gene have been associated with psychosis transition. However, the neurobiological changes associated with these SNPs remain unclear. We aimed to determine what relationship these two SNPs have on lateral ventricular volume and white matter integrity, as abnormalities in these brain structures are some of the most consistent in schizophrenia.

METHODS

Structural (n = 370) and diffusion (n = 465) magnetic resonance imaging data were obtained from affected and unaffected individuals predominantly of European descent. The SNPs rs4281084, rs12155594, and their combined allelic load were examined for their effects on lateral ventricular volume, fractional anisotropy (FA) as well as axial (AD) and radial (RD) diffusivity. Additional exploratory analyses assessed NRG1 effects on gray matter volume, cortical thickness, and surface area throughout the brain.

RESULTS

Individuals with a schizophrenia age of onset ⩽25 and a combined allelic load ⩾3 NRG1 risk alleles had significantly larger right (up to 50%, p adj = 0.01) and left (up to 45%, p adj = 0.05) lateral ventricle volumes compared with those with allelic loads of less than three. Furthermore, carriers of three or more risk alleles, regardless of age of onset and case status, had significantly reduced FA and elevated RD but stable AD in the frontal cortex compared with those carrying fewer than three risk alleles.

CONCLUSIONS

Our findings build on a growing body of research supporting the functional importance of genetic variation within the NRG1 gene and complement previous findings implicating the rs4281084 and rs12155594 SNPs as markers for psychosis transition.

Striatal but not frontal cortical up-regulation of the epidermal growth factor receptor in rats exposed to immune activation in utero and cannabinoid treatment in adolescence

In utero maternal immune activation (MIA) and cannabinoid exposure during adolescence constitute environmental risk factors for schizophrenia. We investigated these risk factors alone and in combination ("two-hit") on epidermal growth factor receptor (EGFR) and neuregulin-1 receptor (ErbB4) levels in the rat brain. EGFR but not ErbB4 receptor protein levels were significantly increased in the nucleus accumbens and striatum of "two-hit" rats only, with no changes seen at the mRNA level. These findings support region specific EGF-system dysregulation as a plausible mechanism in this animal model of schizophrenia pathogenesis.

Percutaneous re-circulating isolated limb perfusion of gentamicin in a large animal model: targeted delivery of gentamicin to limb

OBJECTIVE

We have developed a percutaneous recirculation system (V-Vascular, V-V) to enable delivery of high levels of antibiotic to the limb in an isolated and targeted manner for the treatment of limb infection.

BACKGROUND

Chronic and acute limb infections are relatively commonplace in a variety of wound types. Infection can become refractory to existing treatment strategies and can cause complications associated with wound healing, lead to amputation and even death.

METHODS

Gentamicin was delivered to the ovine hind limb (4 mg/kg) using the V-V system, a 'closed' recirculatory catheter system that draws blood from the venous system and returns it to the artery via an oxygenator, or via intra-venous (IV) infusion. Samples of muscle, bone and synovial fluid of the limb were collected at 30 and 60 min post administration of gentamicin.

RESULTS

There was a significantly greater concentration of gentamicin observed in the bone and skeletal muscle of limbs receiving the antibiotic via V-V at 30 min post administration compared to IV delivery, (bone V-V 0.05 ± 0.04, I.V 0.004 ± 0.001 mg/L p<0.05; muscle V-V 0.005 ± 0.001, I.V 0.002 ± 0.0005 mg/L p<0.05) and bone and synovial fluid at 60 min post administration (bone V-V 0.06 ± 0.02, I.V 0.005 ± 0.001 mg/L p<0.05; synovial fluid V-V 34.58 ± 14.9, I.V 3.03 ± 0.59 mg/L p<0.05).

CONCLUSIONS

These results suggest that the use of percutaneous recirculation is a safe and effective method for delivering a greater concentration of antibiotic to the limb without systemic implications.

Host rather than graft origin of Matrigel-induced adipose tissue in the murine tissue-engineering chamber

We have recently shown that Matrigel-filled chambers containing fibroblast growth factor-2 (FGF2) and placed around an epigastric pedicle in the mouse were highly adipogenic. Contact of this construct with pre-existing tissue or a free adipose graft was required. To further investigate the mechanisms underpinning formation of new adipose tissue, we seeded these chambers with human adipose biopsies and human adipose-derived cell populations in severe combined immunodeficient mice and assessed the origin of the resultant adipose tissue after 6 weeks using species-specific probes. The tissues were negative for human-specific vimentin labeling, suggesting that the fat originates from the murine host rather than the human graft. This was supported by the strong presence of mouse-specific Cot-1 deoxyribonucleic acid labeling, and the absence of human Cot-1 labeling in the new fat. Even chambers seeded with FGF2/Matrigel containing cultured human stromal-vascular fraction (SVF) labeled strongly only for human vimentin in cells that did not have a mature adipocyte phenotype; the newly formed fat tissue was negative for human vimentin. These findings indicate that grafts placed in the chamber have an inductive function for neo-adipogenesis, rather than supplying adipocyte-precursor cells to generate the new fat tissue, and preliminary observations implicate the SVF in producing inductive factors. This surprising finding opens the door for refinement of current adipose tissue-engineering approaches.