Phase 1 clinical study of cell therapy with effective-mononuclear cells (E-MNC) for radiogenic xerostomia (first-in-human study) (FIH study on E-MNC therapy for radiogenic xerostomia)

BACKGROUND

Treatment for most patients with head and neck cancers includes ionizing radiation with or without chemotherapy. This treatment causes irreversible damage to salivary glands in the irradiation field accompanied by a loss of fluid-secreting acinar cells and a considerable decrease of saliva secretion. There is currently no adequate conventional treatment for this condition. In recent years, we developed an effective culture method to enhance the anti-inflammatory and vasculogenic phenotypes of peripheral blood mononuclear cells (PBMNCs), and such effectively conditioned PBMNC (E-MNC) therapy has shown promising improvements to the function of radiation-injured salivary glands in preclinical studies. However, the safety and effect of E-NMC therapy have yet assessed in human. The objective of this ongoing first-in-man study is to assess the safety, tolerability, and in part the efficacy of E-MNC therapy for treating radiation-induced xerostomia.

METHODS/DESIGN

This phase 1 first-in-man study is an open-label, single-center, two-step dose escalation study. A total of 6 patients, who had no recurrence of head and neck cancer over 5 years following radiation therapy and suffered from radiation-induced xerostomia, will receive a transplantation of E-NMCs derived from autologous PBMNCs to a submandibular gland. The duration of the intervention will be 1 year. To analyze the recovery of salivary secretion, a gum test will be performed. To analyze the recovery of atrophic salivary glands, computed tomography (CT), and magnetic resonance imaging (MRI) of salivary glands will be conducted. The primary endpoint is the safety of the protocol. The secondary endpoints are the changes from baseline in whole saliva secretion and salivary gland atrophy.

DISCUSSION

This will be the first clinical study of regenerative therapy using E-MNCs for patients with severe radiation-induced xerostomia. The results of this study are expected to contribute to developing the low-invasive cell-based therapy for radiation-induced xerostomia.

TRIAL REGISTRATION

This study was registered with the Japan Registry of Clinical Trials (http://jrct.niph.go.jp) as jRCTb070190057.

Implication of altered α7 nicotinic receptors and amyloid deposition in the Alzheimer's brain

Introduction

Brain amyloid-β protein (Aβ) deposition is a key pathology of Alzheimer's disease (AD). Cholinergic degeneration, including reductions in α7 nicotinic acetylcholine receptors (α7-nAChR), is also known as a pathophysiology of AD. Recent imaging studies have shown cognitively normal subjects with Aβ depositions, indicating a missing link between Aβ deposition and cognitive decline.

Objectives

To clarify relationships among the Aβ burden, α7-nAChR availability, and cognitive declines in AD.

Aims

To measure brain Aβ deposition and α7-nAChR availability in the same patients with AD using positron emission tomography (PET).

Methods

Twenty AD patients and age-matched 20 healthy adults were studied. The α7-nAChR availability and Aβ deposition were evaluated using PET with [11C]MeQAA and [11C]PIB, respectively. Levels of specific binding were estimated by a simplified reference tissue method (BPND) for [11C]MeQAA and a tissue ratio method (SUVR) for using [11C]PIB. The values were compared with clinical measures of various cognitive functions using regions of interest (ROIs)-based and statistical parametric mapping (SPM) analyses.

Results

[11C]MeQAA BPND levels were extensively lower in the cholinergic projection regions of AD. There was a significant negative correlation between [11C]PIB SUVR and [11C]MeQAA BPND in the nucleus basalis of Mynert (NBM). The NBM [11C]PIB SUVR was negatively correlated with the [11C]MeQAA BPND level in the anterior and posterior cingulate cortices, whereas the relation within the same region showed weak correlation. Also we found significant correlation between cognitive decline and [11C]MeQAA BPND levels in the NBM.

Conclusions

Aβ deposition-linked α7-nAChR dysfunction may account for cognitive decline in AD.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Structural relationship of kappa-type light chains with AL amyloidosis: multiple deletions found in a VkappaIV protein

Two amyloidogenic Bence Jones proteins (Am37 VkappaIV and NIG1 VkappaI) and one non-amyloidogenic protein (NIG26 VkappaIII) were characterized. The protein Am37 had four deletions when compared with the translated germ-line gene sequence: two Ser residues following position 27 (27e, 27f) in CDR1 and two amino acids Pro-44, and Tyr-49 in FR2 were deleted. A strictly conserved salt-bridge-forming amino acid, Asp-82, was replaced by the hydrophobic residue Leu. In a comparative study of amyloidogenic and non-amyloidogenic proteins, five amino acids (Ser-10, Ala-13, Ser-65, Gln-90, and Ile-106) were found to be unique to NIG1 and several other amyloidogenic proteins. Additional substitutions also occur within these proteins. These substitutions might be significant in altering protein folding as well as in contributing to their aggregation as amyloid fibrils.

Structural relationship of lambda-type light chains with AL amyloidosis

Three human amyloidogenic Bence Jones proteins, NIG76 VlambdaII, NIG204 VlambdaI, and NIG250 VlambdaV, were characterized. In a comparative study, three amino acids, Ser-25a, Thr-68, and Val-95, were found to be common to amyloidogenic proteins of the VlambdaII subgroup. NIG204 had an insertion of Pro residue following position 30 (30a). Proteins having an insertion at this position are invariantly amyloidogenic. NIG250 had a characteristic VlambdaV VL domain, with Mcg+ and KERN+ CL domain isotypes. Following the protein DEL, this is the second example of this subgroup. No common residue is found in the other subgroup proteins but unique substitutions do occur. It would seem that any substitution that causes an alteration in the protein conformation may lead to its being more prone to association with the amyloid processes.