Alterations of NK Cell Phenotype During Pregnancy in Multiple Sclerosis.

In multiple sclerosis (MS), relapse rate is decreased by 70-80% in the third trimester of pregnancy. However, the underlying mechanisms driving this effect are poorly understood. Evidence suggests that CD56bright NK cell frequencies increase during pregnancy. Here, we analyze pregnancy-related NK cell shifts in a large longitudinal cohort of pregnant women with and without MS, and provide in-depth phenotyping of NK cells. In healthy pregnancy and pregnancy in MS, peripheral blood NK cells showed significant frequency shifts, notably an increase of CD56bright NK cells and a decrease of CD56dim NK cells toward the third trimester, indicating a general rather than an MS-specific phenomenon of pregnancy. Additional follow-ups in women with MS showed a reversal of NK cell changes postpartum. Moreover, high-dimensional profiling revealed a specific CD56bright subset with receptor expression related to cytotoxicity and cell activity (e.g., CD16+ NKp46high NKG2Dhigh NKG2Ahigh phenotype) that may drive the expansion of CD56bright NK cells during pregnancy in MS. Our data confirm that pregnancy promotes pronounced shifts of NK cells toward the regulatory CD56bright population. Although exploratory results on in-depth CD56bright phenotype need to be confirmed in larger studies, our findings suggest an increased regulatory NK activity, thereby potentially contributing to disease amelioration of MS during pregnancy.

Four reasons why too many informed consents to clinical research are invalid: a critical analysis of current practices.

OBJECTIVE: Informed consent (IC) is a central ethical and legal requirement for clinical research that aims to protect the autonomy of participants. To enable an autonomous decision and valid consent, adequate understanding must be ensured. However, a considerable proportion of participants do not understand the relevant aspects about participation in research, for example, approximately 45% could not name at least one risk. As such, the inadequate understanding of IC has been known for several decades, and it still constitutes a severe problem for the ethical conduct of research. Through delineating the most pressing deficits of current IC procedures that lead to insufficient understanding, we aim to encourage the discussion among stakeholders, for example, clinical researchers, and to provide the grounds for practical solutions. MAIN ARGUMENTS: (1) IC documents are too long to be read completely, thus, make it very difficult for potential participants to identify the material facts about the trial. (2) The low readability of the IC documents disadvantages persons with limited literacy. (3) The therapeutic misconception frequently prevents participants to realise that the primary purpose of clinical research is to benefit future patients. (4) Excessive risk disclosures, insufficient information about expected benefits and framing effects compromise a rational risk/benefit assessment. CONCLUSION: Due to these deficits, practices of IC in clinical research too often preclude adequate understanding of prospective participants, thus, invalidating IC. The gap between the well-specified ethical norm to enable IC and its insufficient translation into practice can no longer be accepted, as participant rights and the public trust in responsible research are at stake. Hence, immediate action is needed to address the prevailing deficits.

Challenges and proposed solutions in making clinical research on COVID-19 ethical: a status quo analysis across German research ethics committees.

BACKGROUND: In the course of the COVID-19 pandemic, the biomedical research community's attempt to focus the attention on fighting COVID-19, led to several challenges within the field of research ethics. However, we know little about the practical relevance of these challenges for Research Ethics Committees (RECs). METHODS: We conducted a qualitative survey across all 52 German RECs on the challenges and potential solutions with reviewing proposals for COVID-19 studies. We de-identified the answers and applied thematic text analysis for the extraction and synthesis of challenges and potential solutions that we grouped under established principles for clinical research ethics. RESULTS: We received an overall response rate of 42%. The 22 responding RECs reported that they had assessed a total of 441 study proposals on COVID-19 until 21 April 2020. For the review of these proposals the RECs indicated a broad spectrum of challenges regarding (1) social value (e.g. lack of coordination), (2) scientific validity (e.g. provisional study planning), (3) favourable risk-benefit ratio (e.g. difficult benefit assessment), (4) informed consent (e.g. strict isolation measures), (5) independent review (e.g. lack of time), (6) fair selection of trial participants (e.g. inclusion of vulnerable groups), and (7) respect for study participants (e.g. data security). Mentioned solutions ranged from improved local/national coordination, over guidance on modified consent procedures, to priority setting across clinical studies. CONCLUSIONS: RECs are facing a broad spectrum of pressing challenges in reviewing COVID-19 studies. Some challenges for consent procedures are well known from research in intensive care settings but are further aggravated by infection measures. Other challenges such as reviewing several clinical studies at the same time that potentially compete for the recruitment of in-house COVID-19 patients are unique to the current situation. For some of the challenges the proposed solutions in our survey could relatively easy be translated into practice. Others need further conceptual and empirical research. Our findings together with the increasing body of literature on COVID-19 research ethics, and further stakeholder engagement should inform the development of hands-on guidance for researchers, funders, RECs, and further oversight bodies.

Fingolimod Therapy in Multiple Sclerosis Leads to the Enrichment of a Subpopulation of Aged NK Cells.

Fingolimod is an approved oral treatment for relapsing-remitting multiple sclerosis (RRMS) that modulates agonistically the sphingosin-1-phosphate receptor (S1PR), inhibiting thereby the egress of lymphocytes from the lymph nodes. In this interventional prospective clinical phase IV trial, we longitudinally investigated the impact of fingolimod on frequencies of NK cell subpopulations by flow cytometry in 17 RRMS patients at baseline and 1, 3, 6, and 12 months after treatment initiation. Clinical outcome was assessed by the Expanded Disability Status Scale (EDSS) and annualized relapse rates (ARR). Over the study period, median EDSS remained stable from month 3 to month 12, and ARR decreased compared to ARR in the 24 months prior treatment. Treatment was paralleled by an increased frequency of circulating NK cells, due primarily to an increase in CD56dimCD94low mature NK cells, while the CD56bright fraction and CD127+ innate lymphoid cells (ILCs) decreased over time. An unsupervised clustering algorithm further revealed that a particular fraction of NK cells defined by the expression of CD56dimCD16++KIR+/-NKG2A-CD94-CCR7+/-CX3CR1+/-NKG2C-NKG2D+NKp46-DNAM1++CD127+ increased during treatment. This specific phenotype might reflect a status of aged, fully differentiated, and less functional NK cells. Our study confirms that fingolimod treatment affects both NK cells and ILC. In addition, our study suggests that treatment leads to the enrichment of a specific NK cell subset characterized by an aged phenotype. This might limit the anti-microbial and anti-tumour NK cell activity in fingolimod-treated patients.