An Introduction to Cord Blood
What is Cord It?
Cord blood, also called placental blood, is found in the umbilical cord and placenta of newborn babies. After a baby is born, and the umbilical cord cut, the baby has no more use for the blood that remains in these organs. Although cord blood is made up of the same components as any other blood, the plethora of hematopoietic cells present is what makes it special. Hematopoietic are immature, or primitive, cells which still have the potential to form into platelets, or red or white blood cells. With some scientific intervention, they may even be able to for into other cell types that make up your body.
Normal blood is made up of red and white cells, platelets, and plasma. Until a few years ago, it was believed that only cord blood contained hematopoietic stem cells. Medical science now knows that venous blood and menstrual blood also contains some blood-forming cells that can be used as stem cell sources, but cord blood remains the best option. This is because cord blood contains a much higher concentration of hematopoietic cells.
Hematopoietis is the process by which new, healthy blood cells are generated, and only naturally occurs in the blood marrow after a person is born. Extracting bone marrow is an invasive and painful procedure, and must be collected from a healthy subject who is a donor match to treat ailments. Cord blood is so valuable because it can be gathered easily and painlessly, versus the difficulty of extracting marrow. Banking a person's cord blood for personal use upon their birth also eliminates the need to find a donor match.
Why Save it?
As a natural, simple source of blood-forming stem cells, there is currently no better source than cord blood. Parents have the option of either saving their cord blood, or donating it for public use. Just like any blood bank, saving cord blood helps save lives every day.
Uses and Applications
There are over 80 different diseases that can be treated with cord blood, with more expected to be discovered in the near future. Currently, those 80 fall into 14 categories of disease.
- Bone Marrow Failure Syndromes
- Immune Deficiencies
- Metabolic/Storage Diseases
- Platelet Disorders
- Neutrophil Disorders
- Autoimmune Diseases, such as HIV
- Epidermolysis Bullosa
- Other Malignancies, Including: Breast Cancer, Plasma Cell Disorder, Neuroblastoma
Although cord blood cannot necessarily treat every disease in each category, new treatment vectors are always being researched to expand the number of treatable conditions. Research is currently ongoing in its use for treating traumatic brain injuries, type one diabetes, stroke-induced brain damage, hearing loss, and cardiovascular repair related to a myocardial infarction.
Cord blood is also being studied for treatment efficacy outside of diseases of the blood. However, while still considered promising, its use in other regenerative stem cell applications remains challenging for scientists. Donating cord blood for public use gives scientists a supply of hematopoietic cells from which they may derive these new treatments.
The Importance of Cord Blood for Ethnic Minorities
Every ethnic group shares certain markers in their genetic code, and this is reflected in the HLA type of their blood. The HLA, or human leukocyte antigen, system is a major component of your immune system, and each group type is indicative of the proteins that a person’s body recognizes as native or foreign. Your HLA determines from whom you can and can’t receive transplants. Because certain HLA types are largely present only in one ethnic population, this can make it difficult for minority populations to find a blood-producing stem cell match when needed for medical treatment. Treatments for diseases such as leukemia, lymphoma, sickle cell, and other disorders of the blood, all require such donors.
Due to their ancestor’s historic isolation from genetic intermingling, African Americans often have an especially difficult time finding donor matches. Not only is their HLA type variation much greater, many African-Americans carry unique mixes of European and African ancestry, creating novel HLA combinations. The end result is that a person with African ancestry may require at least three times as many donors to find a bone marrow match than a Caucasian patient. Sickle cell treatment, in particular, benefits from a patient receiving cord blood from a closely related donor.
The difficulty in finding a donor match stems not only from uncommon HLA types, but most importantly, is a factor of sheer numbers. There are simply not as many potential donors for minority patients in the United States. Although there are occasionally matches between ethnic groups, they are rare. For this reason, minority patients, especially those with no Caucasian ancestors, can benefit from cord blood programs established in the global region from which their ancestors originate.
Due to these factors, a compelling argument for private cord blood banking for minority patients can be made. As it pertains to the general argument in the medical and cord blood industry, this is another reason why cord blood donation by minority mothers is also strongly encouraged. The most beneficial aspect of cord blood versus bone marrow donation for minority patients is that cord blood. only be a partial match for the recipient’s body to accept it.
Cord Blood Drawbacks
While there are many reasons to recommend cord blood storage and use, patients should be aware of the limitations and possible drawbacks of treatments derived from cord blood. Cord blood is not always the best option for some treatments, or may be best used in conjunction with other treatment options.
Unlike bone marrow, the volume of cord blood is comparatively small and, of course, fixed. This means that the population of available stem cells viable for transplant is also limited, as they can't be reproduced. The total nucleated cells per kilogram of a patient's weight equals only about a tenth of a bone marrow cell graft. What this means for the patient is an elevated risk of infection immediately after transplant, because the replication return rate is slower, lengthening the engraftment period. Cord blood treatments are therefore least problematic in infants and small children. By adolescence, the typical patient is of a size that the required number of cells needed for a graft outstrips that of the cord blood's maximum effectiveness.
Additionally, because cord blood donation, by its very nature, is a one time event, multiple donors may be necessary. Should a patient need an additional donation, due to treatment failure or to help fight off a recurrence of lymphoma, a cord blood match from another donor needs to be found.
Another possible complication that must be considered is the possibility of the recipient developing diseases of the blood or immune system carried by the donor. This is, of course, only a factor in patients receiving cord blood that was not collected at the time of their birth. Testing for genetic diseases in all cord blood collected is of the utmost importance for this reason. Medical science continues to move forward, though, and even cord blood thoroughly screened may carry a disease which may not be screened for, or even known, at the time of collection. The danger here should not be overblown, however, as all medical procedures carry some risk. Any genetic disease that would not be caught with current screening procedures is exceptionally rare.
Umbilical Cord Tissue Collection
The collection and use of umbilical cord tissue is a relatively new procedure, and offers a new branch from which to develop disease treatments. Collected cord tissue is an excellent source of mesenchymal stromal cells, or MSC. These cells, as defined by the Mesenchymal and Tissue Stem Cell Committee of the International Society for Cellular Therapy, offer considerable potential in future therapeutic uses for building bone, cartilage, connective tissues, and inflammatory disorders. Although no human clinical trials using umbilical MSC cells have been done yet, recent clinical trials using MSC collected from adult bone marrow have yielded results in treatments for stroke, bone diseases and injuries, heart disease, diabetes, multiple sclerosis, and Crohn's disease. Additionally, over 50 clinical trials using animal-derived umbilical MSC have been conducted, and have successfully treated, the animal corollary versions of Parkinson's disease, lung cancer, rheumatoid arthritis, type 1 diabetes, and cartilage injuries.
New parents should consider collecting the tissue in addition to cord blood, as it can also potentially double the amount of stem cells collected. Parents should also be aware that there is currently no set standard for cord tissue storage. A facility may extract stem cells before storage, or freeze a complete section of cord tissue. The former has the advantage of harvesting stem cells immediately in compliance with FDA regulations for therapeutic use, but may not be useful for future treatment methods. Storing a complete tissue sample has the advantage of possibility of being useful for future therapeutic treatments, but is dependent upon cell separation technological developments.
Cord Blood Banking
How Is It Collected and Tested?
Until the uses of cord blood were discovered, the umbilical cord and placenta were just thrown out. The cord blood collection procedure simply adds a step between birth and discarding the afterbirth. After the baby is delivered, but before the mother passes the placenta, the attending physician extracts the blood from the cord. Using a small needle, a tube is attached to the umbilical cord, which feeds the blood into the same type of silicon bag used when adults donate blood. This procedure only takes a few minutes, and is non-invasive for mother and child, as the cord has already been severed from the baby. Many hospitals take at least a small sample of cord blood whether or not the mother is donating, to test for any blood-borne disease, especially when there have been complication during pregnancy or birth.
Once collected, technicians test a small sample of the blood. Tests include, but under certain circumstances, may not be limited to:
- HLA-A, -B and -DRB1 Typing. This tests for the blood’s human leukocyte antigen (HLA) type, which are the proteins found on the surface of white blood cells. These are related to a person's immune system antibodies. The mother's type will also be taken to ensure that the “mother's” sample wasn't mistakenly taken from someone else, and acts as a safety measure to insure against mix-ups should the blood be used.
- CD34+ Cell Number. This assesses CD34+ cell viability and count both before and after processing.
- Bacterial Culture. The sample is screened for bacterial infection, and is sent off to a microbiology laboratory for further testing if it tests positive.
- Nucleated Cell Total. This assesses the sample’s total nucleated cell count (TNC), and screens for a normal population.
- Colony Forming Unit Assay. This detects how many colony-forming erythroid lineage units are present in the sample, and helps detect hematopoietic disorders.
- Infectious Diseases. All samples should undergo the same tests for virus antigens and antibodies that blood received from a traditional donation.
- Hemoglobinopathies Screening. This tests for the presence of C and E sickle cell hemoglobins.
- Nucleic Acid Testing. This is only done on the mother’s sample, and detects HVC, HIV, and West Nile Virus.
- RH Type and ABO Blood Grouping. These are the basic classifications for blood types matching.
- Cytomegalovirus Testing. This tests both the cord blood and mother’s blood samples for the antibody which indicate any exposure to the virus. Many companies also take and test the infant’s saliva.
How Long Can It Be Stored?
Because cord blood use is still a relatively new medical procedure, the expiration date for viability is still unknown. So far, the oldest frozen units used were 13 years old, but tested samples collected as early as 1993 have yet to show any deterioration, and are likely still viable. Liquid nitrogen storage is an exceptionally effective method of preserving biological samples for extended periods of time, as long as they are left undisturbed. The industry standard in cord blood storage mandates that each sample is kept in its own self-contained cryogenic device within a larger unit, so as to keep conditions constant.
The cord blood banking industry has grown by leaps and bounds since the year 2000, and there are many options for those who would like to store or donate their cord blood. Although this growth in the industry means a better selection of service providers, it means you must be more careful when selecting a company.
Should You Use a Public or Private Facility?
The cord blood industry is tightly regulated, so when deciding between companies, your first concern should be if they meet the national certification requirements of your country. In the United States, the collection, storage, processing, packaging, and distribution is regulated by the FDA, and applies to both public and private banks, but should not be mistaken for an endorsement.
While the United States doesn't have a national cord blood stem cell bank, 17 states have enacted legislation to ensure that expectant parents are informed and educated regarding their cord blood options. The Health Resources and Services Administration department of Health and Huuman Services also actively funds marrow and cord blood donor registration. The medical community in the United States is currently in support of creating, at minimum, a national registry which would serve to keep make finding a potential match easier for patients, and possibly, allow them to contact those with privately stored blood.
Privately storing stem cells remains controversial. This largely stems from the fact that aside from rare genetic occurrences, a patient is likely to find a public match, because of the nature of a cord blood match. According to a study published in the Biology of Blood and Marrow Transplantation medical journal, the probability of an individual, with a life expectancy of 70 years, requiring a stem cell transplant is 1 in 217. Matched versus collected from the patient's own cord blood, this breaks down as patients needing transplantation from their own stem cells at 1 in 435, while the odds of requiring a donation from a matching donor is a remarkably similar 1 in 400.
Additionally, stem cells collected from a patient's cord blood, also known as autologous cord blood, cannot be used to treat diseases that stem from genetic conditions, such as childhood leukemia. This is because the therapeutic effect of the stem cells is derived from introducing cells which do not carry those genetic defects. Exceptions for autologous stem cell use apply for the treatment of pediatric cancers and conditions which have been acquired, and do not have genetic signatures. It may also be used for type one diabetes, brain injuries, and cerebral palsy.
For these reasons, the World Marrow Donor Association, and general scientific community, strongly recommend public donation over private storage, unless a disease which can be treated with autologous stem cells runs in your family. Some facilities also offer private storage for families which allow the cells to be used by any member of the family you authorize. Still, according to the University of California, San Francisco, the odds are only 1 in 2,500 per family member that they will be able to make use of family stem cells. Whether the expense of private storage is justified or not is still up to the individual.
How Much Does it Cost to Save?
Public storage costs per cord blood unit generally costs a facility about $1,500 total for collection, processing, and storage. While private institutions do not release data in this regard, it can be safely assumed that the their expenses are comparable. Private cord blood bank rates vary, but generally run between $775 to $2,150 for enrollment, and then an ongoing annual fee that ranges anywhere from $85 to $150 per year. Annual payments can often be lowered by putting down a larger down payment at enrollment, or may offer a payment plan. Some companies also offer free of discounted banking for families in immediate need of the cord blood for donation.
What to Look for in a Cord Blood Bank?
Should you decide to privately bank your baby's cord blood, you should discuss it with your medical practitioner, as they may have some local recommendations. The decision should, ideally, be made before the third trimester, in order to ensure everything is in place when the baby is born. Most doctors and midwives are willing and able to collect cord blood, but some may charge a fee, so make sure you're prepared.
In the United States, your chosen cord blood bank should be accredited by the American Association of Blood Banks. You can find a list of member banks at their website. These include public and private institutions. Similar accreditation organizations oversee blood banking in every country, and should be consulted before deciding on a facility. Once you've narrowed your list of choices, contact the companies to learn about their rates and policies. Knowing what to ask is key. While you may have your own individual concerns, make sure you ask the following questions.
- Is the cord blood bank private or publicly held?
- Are they affiliated with a research group, hospital, or bio-technology research and development group? If so, do some research on the affiliated institution.
- How long have they been banking cord blood?
- Do the offer other medical services?
- Who is charged with the daily operations of the facility? Many banks are associated with big names in the medical community, but those individuals are often not involved in daily operations.
- What are their collection and storage policies? Are they in compliance with federal standards?
- How many cord blood units has the facility actually release for use? Do they have a good viability rate? While proper collection and storage are important, the proper pulling and delivery of a unit is equally vital.
- How large is their cord blood inventory? This statistic should include public and private stocks, as some companies may house both, and will give you an idea of how much experience they have in storage.
- How stable is the company? Banks with a long record of success are preferable, as they're less likely to out of business, but newer facilities may offer their own advantages. In either case, be sure that the company is in no immediate danger of folding.
- Should the company shut its doors, what happens to the cord blood stored with them?
Resources for Cord Blood Donors
Private Cord Blood Banking
After you've decided on which facility you will be baking with, you should immediately make arrangements. The bank should send you a collection kit in the mail, which should include medical forms and sealed supplies. Do not open these, as they need to remain sterile. Keeping this kit packed and ready with the rest of the items you'll be taking to the hospital at the onset of labor is advised. Also make sure that your practitioner is aware that you'll need the blood collected.
When you go into labor, someone should notify the cord blood bank, so that they can send a courier to transport the unit upon collection. As with any biological materials, time is essential to the health of the collected material. If you know whom the medical staff member is who will be collection the cord blood, give them this information as well. The unit should arrive at the storage facility within 36 hours of collection. The facility should contact you when the unit arrives, and be able to tell you how much they were able to store.
Public Cord Blood Donation
If you decide to donate, you will still need to make certain arrangements ahead of time, as much of the process is the same for public and private collection. Donation is free, but your options will vary depending on where you live. Donors will need to register by the 34th week of pregnacy and will have to meet donation criteria. The bank will also need you to sign a consent form, provide your medical history, and will collect a small blood sample right before delivery. Some public options may also send a collection kit, which should be treated in the same manner as kits provided by priavte banks.
Many hospitals are affiliated with the national cord blood donation program which is run by the National Marrow Donor Program. The collection and storage process will be easiest if you give birth at an affiliated hospital. If you are giving birth at home, or at an unaffiliated hospital, you will need to find another public bank which can take your donation. A list of these facilities can be found at the Parent's Guide to Cord Blood website. If there aren't any local public banks in your area, try contacting either Lifeforce Cryobanks or Lifebank USA.
On the big day, make sure you have someone designated to notify the blood bank so that they can send a courier to collect the unit from the medical staff. If you're working with a facility not affiliated with the NMDP program, you may need to arrange to give the cord blood directly to the medical courier. Once given to the courier, you need not have any more direct connection to the facility, but many banks will let you check on your donation to see if it was accepted for storage or used for treatement.
Resources for Cord Blood RecipientsThere are a few ways that patients in search of a cord blood donation may find a match. For indivduals and families, the best option is a public, or prelimiary, search. This is usually conducted by contactinf family, friends, and the general public and making it known that you are in search of a donation. A basic low resolution HLA typing profile should be used to narrow down possible donors.
Medical personnel have access to the National Cord Blood Program's online search engine, and is usually the initial resource for finding low and high resolution HLA matches. Transplant centers can submit a registry search directly through the NCBP via fax or their website. The results from these requests include the sample's nucleated cell dose in addition to HLA typing.
Canada, the United Kingdom, Japan, and various other countries have national cord blood banks which collect, process, and store cord blood. Many of these national banks will donate to patients in other countries, and are a good option for minority patients or anyone with uncommon genetic ancestry. International donation registries can be accesed by registered medical personell via the The Caitlin Raymond International Registry. This orgination also has the resources to facilitate international donor coordination.