**2. Cell sources for transplantation**

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 marrow transplants for the treatment of some specific cancers.

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 options.

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 hard and slow work.

**5**

**Table 1.**

**Cell type**

iPSC Skin biopsy

MSC Bone marrow or adipose tissue

EpPC Donor tissue

**Harvest method**

*Current Status of Stem Cell Therapy for Sepsis and Acute Respiratory Distress Syndrome*

Several pharmaceutical companies hold a number of stem cell lines and work to advance in cell therapies. Finding new culture mediums that able to maintain or differentiate into the desired cell type with high throughput and also diminish the risk of causing cancer is quite difficult. Afterwards, the laboratories and the companies will need to implement several protocols to work under good manufacturing practice guidelines (GMP) and follow specific storage rules of products that want to be used as a therapy. Several delicate conditions need to be fulfilled for these cells, to be approved by health authorities, and to be used in humans and in clinical trials. First, we want to review the different cell types, their potential sources, and characteristics and underlie why mainly mesenchymal stem/stromal cells are used for the treatment of sepsis and ARDS. Some pre-clinical studies using induced pluripotent stem cells (iPSC) for the treatment of both syndromes and alveolar type II cells for ARDS treatment also presented some interesting results. The different

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

A new type of pluripotent cells, iPSCs, can be obtained by reprogramming animal and human somatic (differentiated) cells. Usually, iPSCs are obtained from dermal fibroblasts because it is an easy source and did not produce any damage to the donor when we obtain them. The cells should be dedifferentiated following

**Advantages Disadvantages Benefits in ARDS Benefits in sepsis**

Easy to differentiate to AEC2. No tested *in vivo*

Easy to differentiate to AEC2. No tested *in vivo*

Immunomodulatory effect. Reduces inflammation and lung

Maintains the integrity of the lung and improves the

edema

lung function

AEC2 cells were tested improving lung function and reducing inflammation

Reduces mortality and decreases lung inflammation

Reduces mortality and inflammation. Antibacterial activity and antiapoptotic activity

Reduces the sepsis damage re-establishing micro and macrocirculation

—

—

significant ethical issues regarding the use of these cells [17–19].

potential. Ethical problem

High tumorigenic potential

High tumorigenic potential

small amount

Nontumorigenic Difficult isolation and small amount

*DOI: http://dx.doi.org/10.5772/intechopen.86108*

cell subsets are summarized in **Table 1.**

**2.2 Induced pluripotent stem cells (iPSC)**

ESC Embryos Totipotent High tumorigenic

Easy isolation No rejection

Easy isolation No rejection

*Summary of the cell sources and their benefits.*

EnPC Blood Nontumorigenic Difficult isolation and

**2.1 Embryonic stem cells (ESCs)**
