Fecal Microbiota Transplantation in Amyotrophic Lateral Sclerosis: Clinical Protocol and Evaluation of Microbiota Immunity Axis

The fecal microbial transplantation (FMT) is a therapeutic transplant of fecal microbiota from healthy donors to patients. This practice is aimed at restoring eubiosis and rebalancing the enteric and systemic immune responses, and then eliminating pathogenic triggers of multiple disease, including neurodegenerative diseases. Alterations of gut microbiota (GM) affect the central nervous system (CNS) health, impacting neuro-immune interactions, synaptic plasticity, myelination, and skeletal muscle function. T-regulatory lymphocytes (Treg) are among the most important players in the pathogenesis of amyotrophic lateral sclerosis (ALS), altering the disease course. Along with circulating neuropeptides, other immune cells, and the gut-brain axis, the GM influences immunological tolerance and controls Treg's number and suppressive functions. A double-blind, controlled, multicenter study on FMT in ALS patients has been designed to evaluate if FMT can modulate neuroinflammation, by restoring Treg number, thus modifying disease activity and progression.

Persistent human bocavirus 1 infection and tonsillar immune responses

BACKGROUND

Persistent human bocavirus 1 (HBoV1) infection is a common finding in patients suffering from chronic tonsillar disease. However, the associations between HBoV1 infection and specific immune reactions are not completely known. We aimed to compare in vivo expression of T-cell cytokines, transcription factors, and type I/III interferons in human tonsils between HBoV1-positive and -negative tonsillectomy patients.

METHODS

Tonsil tissue samples, nasopharyngeal aspirate (NPA), and serum samples were obtained from 143 immunocompetent adult and child tonsillectomy patients. HBoV1 and 14 other respiratory viruses were detected in NPAs and tonsil tissues by polymerase chain reaction (PCR). Serology and semi-quantitative PCR were used for diagnosing HBoV1 infections. Expression of 14 cytokines and transcription factors (IFN-α, IFN-β, IFN-γ, IL-10, IL-13, IL-17, IL-28, IL-29, IL-37, TGF-β, FOXP3, GATA3, RORC2, Tbet) was analyzed by quantitative reverse-transcription (RT)-PCR in tonsil tissues.

RESULTS

HBoV1 was detected by PCR in NPA and tonsils from 25 (17%) study patients. Serology results indicated prior nonacute infections in 81% of cases. Tonsillar cytokine responses were affected by HBoV1 infection. The suppression of two transcription factors, RORC2 and FOXP3, was associated with HBoV1 infection (p < 0.05). Furthermore, intratonsillar HBoV1-DNA loads correlated negatively with IFN-λ family cytokines and IL-13.

CONCLUSIONS

Our study shows distinctively decreased T-helper₁₇ and T-regulatory type immune responses in local lymphoid tissue in HBoV1-positive tonsillectomy patients. HBoV1 may act as a suppressive immune modulator.

Effect of low dose IL-2 loaded chitosan nanoparticles on natural killer and regulatory T cell expression in experimentally induced autoimmune type 1 diabetes mellitus

Introduction

Natural killer cells (NK) initiate pancreatic islets cell lyses in autoimmune type 1 diabetes mellitus (T1D). Loss of T regulatory cells (Treg) at disease onset facilitates activation and accumulation of NKs in the pancreatic microenvironment. A proper low dose interleukin 2 (IL-2) could enhance Tregs and enforce control and regulation of pro-inflammatory NKs. This relation needs to be studied to improve therapeutic strategies aimed at resetting the balance between Tregs and proinflammatory cells.

Material and methods

We used novel formulations of low dose IL-2 loaded on chitosan nanoparticles. The study included 116 T1D BALB/c mice experimentally induced by streptozotocin, divided into groups. Their splenocytes were maintained in a short-term culture for assessment of expression of CD4⁺Foxp3⁺ Treg and NKp46⁺NK by both flow cytometry and enzyme linked immunoassay (ELISA). In vitro suppressor-assay was used in order to assess the suppressor effect of Treg cells after exogenous IL-2 treatment.

Results

NK cell expression, NKp46 level and NK cell functions were modulated in mice injected with IL-2 loaded chitosan nanoparticles than other groups. A statistical inverse correlation was found between Treg and NK cell expression in IL-2 loaded chitosan with (0.3 µIU) (p = 0.047) and this correlation was related to Foxp3 expression on Treg cells. The modified expression of NK and NKp46 was noticed in mice injected with (0.3 µIU) for longer duration (three weeks) (p < 0.001) but the NK functions did not show any significant changes with prolonged treatment.

Conclusions

Low dose (0.3) µIU IL-2 nanoparticles effectively modulated NK and NKp46 expression. It selectively modulates the suppressive activity of Tregs indicating a significant role of Tregs in NK activation and function by controlling the availability of IL-2 in the microenvironment.

Factors involved in balance of Th17/Treg cells: Clinical implications in inflammatory bowel disease

T-helper 17 (Th17) cells promote tissue inflammation and T-regulatory (Treg) cells inhibit autoimmunity in inflammatory bowel disease (IBD). Thus, the balance between Th17 and Treg cells is crucial. Many factors that influence the generation and maintenance of these cells are also important for appropriate regulation of the Th17/Treg balance; these include TCR signals, costimulatory signals, cytokine signals, Foxp3 stability, metabolic processes, and the microbiota. This article will focus on what we know about these factors, their roles in regulating the Th17/Treg balance, and their clinical implications in IBD.

Circulating T-regulatory cells in neuroblastoma: a pilot prospective study

The objective of our study was to determine baseline Tregs in neuroblastoma patients and correlate with patient characteristics, their change with therapy and at relapse/progression. Flow-cytometric analysis for Treg cells [CD4+CD25+FoxP3+] was done in 14 de novo neuroblastoma patients at diagnosis, post-neoadjuvant chemotherapy and at relapse/progression, along with six healthy controls. Patients had significantly higher baseline Treg frequency than controls [Mean 9.84 ± 3.84 vs 3.16 ± 1.49, P < .001]; higher mean Treg frequency in patients with tumors >10 cm (P = .004) and there was significant reduction in Treg frequency with neoadjuvant chemotherapy when compared with the baseline value [Mean 3.07 ± 1.24 vs 9.72 ± 3.84, P = .007].