Read full article here on how stem cells can reverse the diabetes.

That makes it one almost a year of no posting.

I had been occupied. Too much occupied.

I would be regular now.

More on stem cells soon

That explains why tuberculous bacteria could lie dormant for decades all together.

What happens is master stem cells, produced by bone marrow make a barrier between the T-cells that are supposed to kill the bacteria, and the bacteria.

Proc Natl Acad Sci. Posted online December 6, 2010.

HIV entry into CD4+ cells requires interaction with a cellular receptor, generally either CCR5 or CXCR4.

Previously, the authors had reported a case of an HIV-infected patient in whom viral replication remained absent despite discontinuation of antiretroviral therapy after transplantation with CCR5{Delta}32/{Delta}32 stem cells.

In the present study, authors have demonstrate successful reconstitution of CD4+ T cells at the systemic level as well as in the gut mucosal immune system following CCR5Delta32/Delta32 stem cell transplantation, while the patient remained asymptomatic.

The results strongly suggest that cure of HIV has been achieved in this patient.

Blood: DOI 10.1182/blood-2010-09-309591.

This video explains nicely about cord blood cells.

Click here to view the embedded video.

Click here to view the embedded video.

Almost a year has passed since that post and the site went on to sheer neglect for whatever reasons.

Today I came across a news so exciting, at Medscape that I could not hold myself from posting it.

There is an ongoing trial called Pilot Investigation of Stem Cells in Stroke (PISCES) trial. There is a good news that first patient of the trial has been treated with neural stem cell therapy.

The study is looking at the safety aspects,  neurological effects, clinical and imaging changes.

The stem cells are from a genetically modified immortalized cell line derived from a tissue sample from 12-week fetal cortex.

The PISCES trial is funded by ReNeuron, a company involved in stem cell medical therapy development.

we  must be able to manipulate stem cells so that they possess the necessary characteristics for successful differentiation, transplantation, and engraftment.

The following is a list of steps in successful cell-based treatments that scientists will have to learn to control to bring such treatments to the clinic.

To be useful for transplant purposes, stem cells must be reproducibly made to:

• Proliferate extensively and generate sufficient quantities of tissue.
• Differentiate into the desired cell types.
• Survive in the recipient after transplant.
• Integrate into the surrounding tissue after transplant.
• Function appropriately for the duration of the recipient’s life.
• Avoid harming the recipient in any way.

Graft rejection is a major problem and the methods need to be designed  to avoid the problem. Scientists are experimenting different strategies to overcome the problem.

One of the primary goals of stem cells is to identify how undifferentiated stem cells become the differentiated cells that form the tissues and organs. Here are the areas where stem cells can help the medicine and human race.

Understanding Disease Processes

Some of the most serious medical conditions, such as cancers  are due to abnormal cell division and differentiation. A more complete understanding of the genetic and molecular controls of these processes may provide us with better understanding of the diseases and the enable us to build new therapies.

Additional basic research on the molecular and genetic signals that regulate cell division and specialization would let us identify the steps, triggeres and factors related to these events. we can then effectively control the processes at least in theory.

Test New Drugs

New medications could be tested for safety on differentiated cells generated from human pluripotent cell lines. An in use example of this is testing of anticancer medicines agianst cancer cell lines. The availability of pluripotent stem cells would allow drug testing in a wider range of cell types.

However,for effective drug testing, the precise control of the differentiation of stem cells into the specific cell type on which drugs will be tested would be required.

We lack this precision as of now.

Transplant of Organs/Tissues

This is perhaps the most important, most advertidsed and most talked about potential benefit of stem cells. It involves the generation of  the generation of cells and tissues that could be used for cell-based therapies.

As of today, donated organs and tissues are often used to replace ailing or destroyed tissue, but the need is far more than the available supply.

Stem cells, directed to differentiate into specific cell types, offer the possibility of a renewable source of replacement cells and tissues to treat diseases including Alzheimer’s diseases, spinal cord injury, stroke, burns, heart disease, diabetes, osteoarthritis, and rheumatoid arthritis.

For example, in people with type 1 diabetes, the cells of the pancreas that normally produce insulin are destroyed. It may be possible to direct the differentiation of human embryonic stem cells in cell culture to form insulin-producing cells that eventually could be used in transplantation therapy for persons with diabetes.

Although these cells meet the defining criteria for pluripotent stem cells, it is not known if iPSCs and embryonic stem cells differ in clinically significant ways.

Mouse iPSCs were first reported in 2006, and human iPSCs were first reported in late 2007.

Mouse iPSCs demonstrate important characteristics of pluripotent stem cells, including expressing stem cell markers, forming tumors containing cells from all three germ layers, and being able to contribute to many different tissues when injected into mouse embryos at a very early stage in development.

Human iPSCs also express stem cell markers and are capable of generating cells characteristic of all three germ layers.

Although additional research is needed, iPSCs are already useful tools for drug development and modeling of diseases, and scientists hope to use them in transplantation medicine.

Viruses are currently used to introduce the reprogramming factors into adult cells, and this process must be carefully controlled and tested before the technique can lead to useful treatments for humans.

In animal studies, the virus used to introduce the stem cell factors sometimes causes cancers. Researchers are currently investigating non-viral delivery strategies.

In any case, this breakthrough discovery has created a powerful new way to “de-differentiate” cells whose developmental fates had been previously assumed to be determined. In addition, tissues derived from iPSCs will be a nearly identical match to the cell donor and thus probably avoid rejection by the immune system.

The iPSC strategy creates pluripotent stem cells that, together with studies of other types of pluripotent stem cells, will help researchers learn how to reprogram cells to repair damaged tissues in the human body.

Source: NIH