Navigation Links
A Functional Immune System Can Be Derived From Embryonic Stem Cells, Preliminary Study Finds
Date:2/12/2008

WASHINGTON, Feb. 12 /PRNewswire-USNewswire/ -- A new study demonstrates for the first time that embryonic stem cells can be used to create functional immune system blood cells, a finding which is an important step in the utilization of embryonic stem cells as an alternative source of cells for bone marrow transplantation. This hopeful news for patients with severe blood and immune disorders, who need these transplants for treatment, was prepublished online in Blood, the official journal of the American Society of Hematology.

Embryonic stem cells (ESCs) are being intensely investigated as a renewable source of primitive cells theoretically able to regenerate all tissues and organs. The use of ESC-derived blood-forming cells may have an important advantage over traditional transplants that use bone marrow, umbilical cord blood, and peripheral blood from donors. The antigens on the surface of donated cells must be compatible (determined by a method called HLA matching) with those of the patient to prevent rejection. The use of embryonic stem cells, which have low levels of these antigens and may therefore be less likely to provoke a defensive reaction by the patient's body, may allow patients who can't find suitable HLA-matched donors to receive transplants.

Previous studies have shown that mouse ESCs can be coaxed to form blood-forming hematopoietic cells by introducing a protein called HOXB4, known for its unique ability to greatly enhance cell proliferation, into them. These cells could then be transplanted into mice whose own marrow had been destroyed by radiation, rescuing their marrow function and beginning to produce necessary blood cells. However, previous studies have not investigated whether ESC-derived bone marrow in these mice could regenerate normal immune function -- in particular, if they could allow the mice to respond to viruses or vaccines. Because fetuses have no need for a functional immune system as they are protected from the environment while in the womb, it was unclear if ESC-derived marrow would recreate an immune system at all or just very slowly.

In this study, a team of scientists from Iowa, Taiwan, and Germany used HOXB4-containing ESCs to engraft the bone marrow and rescue mice that genetically lacked any immune system and had been irradiated to destroy their bone marrow. Only cells containing HOXB4 were able to engraft, rescue the mice, and produce blood cells long term. These engrafted cells were shown to be derived from the transplanted ESC-derived cells.

To determine if these transplants were able to rebuild the defunct immune system, the scientists injected the mice with LCMV, a common rodent virus, and watched for T-cell activity, a sign that the body was defending itself against the infection. Although the number of T cells generated by the new hematopoietic cells was low, they were able to respond effectively to the virus. In addition, the transplanted hematopoietic cells were also able to produce B cells and other defensive cells called antigen-presenting cells, which have a role in signaling T cells to action. They also tested the ability of the mice to respond to vaccination and demonstrated the induction of specific immune cells. Although the level of immune response was not what is seen in normal adult mice after exposure to the virus or vaccine, it was measurable and effective.

The study was also encouraging in that none of the 70 transplanted mice followed for more than 200 days developed any tumors -- another concern when using ESCs for tissue regeneration.

"These results show, for the first time, that functional white blood cells, the key players in the body's immune system, can be successfully derived from embryonic stem cells expressing HOXB4," said lead study author Nicholas Zavazava, MD, PhD, Professor of Internal Medicine and Director of Transplant Research at the University of Iowa Hospitals and Clinics in Iowa City and Staff Physician at the Iowa City VA Medical Center. "Therefore, we're hopeful that these exciting findings are the first step toward new, improved therapies for patients."

This study was supported by grant RO1 HL073015 (NIH/NHLBI), a VA Merit Review, and a grant from the Roche Organ Transplantation Research Foundation (ROTRF).

The American Society of Hematology (http://www.hematology.org) is the world's largest professional society concerned with the causes and treatment of blood disorders. Its mission is to further the understanding, diagnosis, treatment, and prevention of disorders affecting blood, bone marrow, and the immunologic, hemostatic, and vascular systems, by promoting research, clinical care, education, training, and advocacy in hematology.

Blood, the official journal of the American Society of Hematology, is the most cited peer-reviewed publication in the field. Blood is issued to Society members and other subscribers twice per month, available in print and online at http://www.bloodjournal.org.


'/>"/>
SOURCE American Society of Hematology
Copyright©2008 PR Newswire.
All rights reserved

Related medicine technology :

1. Genetic Immunity Presents Clinical Data on DermaVir Patch Immune Therapy at 15th Annual Conference on Retroviruses and Opportunistic Infections
2. Pixantrone Shows Activity in a Preclinical Study of Experimental Autoimmune Myasthenia Gravis (EAMG)
3. Steps Toward Stopping Autoimmune Disease: International Consortium Identifies Genes Linked to Lupus
4. Rigel Announces Initiation of Phase 1 Clinical Trial of R348 for Rheumatoid Arthritis, Psoriasis and Other Immune Disorders
5. Researchers Train the Immune System to Deliver Virus That Destroys Cancer in Lab Models
6. Bristol-Myers Squibb, New Jersey Childrens Hospital Launch Center for Immune System Disorders & Infectious Diseases Including HIV/AIDS
7. MedImmune Initiates First Clinical Trial of Monoclonal Antibody Targeting GM-CSFR in Patients with Rheumatoid Arthritis
8. The New England Journal of Medicine Publishes First Clinical Results for MedImmunes Chitinase-like Protein YKL-40 in Patients With Asthma
9. MedImmune Presents New Pharmaco-Economic Data at American Academy of Pediatrics Regarding Infants at High Risk for RSV
10. MedImmune Announces Phase 2 Safety Data for Anti-RSV Antibody and National RSV Surveillance Results
11. Peptimmune Initiates Phase I Study With a Novel Peptide Copolymer for the Treatment of Multiple Sclerosis
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/26/2016)... 2016 A key trend that ... emergence of new treatments. Cardax, a development stage life ... The therapy is expected to fulfil large unmet medical ... conducting studies to develop new treatments for osteoarthritis. One ... involved in osteoarthritis are being investigated, and early trials ...
(Date:5/25/2016)... India , May 25, 2016 ... Animation Market by Type (3D, 2D, 4D), by Therapeutic ... Education), by End User (Medical Device Manufacturers, Hospitals/ Clinics) ... studies the global Medical Animation Market for the forecast ... to reach USD 301.3 Million by 2021 from USD ...
(Date:5/25/2016)... According to market research "Global ... Demand Forecast to 2022 - Industry Insights by Type ... by P&S Market Research, the global insulin delivery device ... it is expected to grow at a CAGR of ... segment is expected to witness the fastest growth at ...
Breaking Medicine Technology:
(Date:5/28/2016)... ... May 28, 2016 , ... May 26, 2016- In search of the ... with theme event of “K Warriors” on June 4, 2016 at Ashbury Hotel and ... event is sponsored and hosted by Shaolin Institute and sanctioned by KSF (Kungfu Sanda ...
(Date:5/27/2016)... ... , ... Two director-level employees of Horizon Blue Cross Blue Shield of New ... honorees. The award recognizes businesswomen who excel in their fields and who have ... MLTSS (Managed Long-Term Services and Supports) Program at Horizon NJ Health and Theresa Ponton, ...
(Date:5/27/2016)... ... May 27, 2016 , ... An educational campaign aimed ... human-interest stories, courtesy of awareness-driven celebrities and thought leaders. It also provides insight ... and industry leaders such as Bioness. , As patients feel increasingly concerned ...
(Date:5/27/2016)... ... May 27, 2016 , ... ... to students studying complementary medicine. Allison Outerbridge is this year’s Life University ... on May 18 at the university’s Student Leadership Awards ceremony. , Outerbridge is ...
(Date:5/26/2016)... (PRWEB) , ... May 26, 2016 , ... ... with discovery of thousands of defective respirators, according to court documents and SEC ... case of William and Becky Tyler v. American Optical Corporation, Case No. BC588866, ...
Breaking Medicine News(10 mins):