**2.1 Embryonic stem cells (ESCs)**

*Innovations in Cell Research and Therapy*

new cases are identified per year [1, 5, 8].

and extracorporeal membrane oxygenation [11–14].

tration into the lung) were used as a treatment.

ies in ARDS and in sepsis and future directions.

row transplants for the treatment of some specific cancers.

**2. Cell sources for transplantation**

syndrome characterized by increased lung permeability, hypoxemia, the absence of cardiogenic pulmonary edema, the disruption of the alveolar-capillary barrier, and widespread inflammation. Every year between 1.5 and 4.5 cases per 100,000 inhabitants/year in Europe is detected and in the United States approximately 200,000

There is no definitive therapy that targets the underlying pathobiology of sepsis exists. Nowadays, the treatment is based on antibiotics, infection source control, fluid resuscitation, and organ support [9, 10]. Moreover, several patients die due to secondary infections during the year after the hospital discharge. After decades of research, and numerous pre-clinical and clinical trials, sepsis and ARDS remain without a specific and effective pharmacotherapy and essentially the management remains supportive. Nowadays, patients with ARDS have been treated with several ventilator interventions such as lower tidal volumes, higher positive end-expiratory pressure (PEEP), and adjuncts such as prone positioning, neuromuscular blockade,

Current advances in the study and knowledge of stem cells have permitted to start using them as a novel treatment for ARDS and sepsis. Based on numerous pre-clinical studies, there is a growing evidence of the potential benefits of cellbased therapies for the treatment of sepsis and ARDS. Several cell types are used in the last years for the treatment of both syndromes showing high efficiency

In animal models, cell therapies have demonstrated noteworthy therapeutic properties including the modulation of the immune system, the release of several factors with growth factor, and antibiotic and anti-inflammatory properties. Cell therapies were tested in several animal models, such as mouse, rat, sheep, and pig models, using several septic and ARDS models. Moreover, different cell types and different administration pathways (intravenously, intraperitoneal, or local adminis-

Furthermore, in the last years, a couple of clinical studies started using cell therapies for the treatment of sepsis and ARDS, and some safety and efficient

This chapter summarizes the different progenitor cells that can be used as a therapy, the mechanisms of action, and the results in pre-clinical and clinical stud-

We define cell therapy as a therapeutic product containing cells, which usually is administered into the patients to replace or repair damaged tissues or cells. Nowadays, several diseases are treated with cell therapies, for example, bone mar-

In the last years, several researchers and physicians are working to convert some cell therapies from potential treatments to real therapies. There is an effort to detect the factors that the cells are secreting and have this beneficial effect and also to set up the safety and efficacy. Additionally, these therapies are really expensive, and there are several problems associated such as the difficulty to obtain, expand, purify, and manipulate these cells. So, we also have to work on the cost-effective

Cell therapies have shown their potential in biomedicine, and their utility for several indications has been demonstrated and this utility will expand in the future. Nevertheless, progressing cell therapies from bench to bedside takes decades of

**4**

options.

hard and slow work.

[15, 16].

results are published.

ESCs are pluripotent cells derived from the inner blastocyst cell mass and constitute a potentially unlimited source of cells that could be differentiated into any progenitor cell and used in the clinical trials. ESCs have high plasticity and theoretically unlimited capacity for self-renewal; ESCs have been suggested for regenerative medicine and tissue replacement; however, their embryologic origin is linked to significant ethical issues regarding the use of these cells [17–19].
