The HeLa cell line is a good example, it was developed using cancerous cells from a woman named Henrietta Lacks without her consent. Cancer tissue does not behave the same way as normal cells and this is what makes it unsuitable for certain types of research or vaccine development. This is what created the need for a normal human cell line.
Leonard Hayflick was able to make impactful contributions to scientific understanding of cell functions and research through his development of this cell line, both directly and indirectly.
Dr. Hayflick’s primary contributions to science is the development of WI-38 cell line and the “Hayflick Limit”, which provides essential insight into the human ageing process on a cellular level. He made many other contributions during his career, however these are the big ones.
The Hayflick Limit is the number of times a cell culture can undergo sub-division before it stops growing. Cancer tissue is not subject to the hayflick limit, it can undergo unlimited sub-divisions. This is a useful property for certain types of research. If there is a need for a specific type of cancer cell they can “transform” them, which is to, in effect make them artificially cancerous.
www.Webofstories.com has published a long series of videos that contain an interview with Dr. Hayflick. The videos are not in the order that he spoke so the clips that are most relevant to the topic of this article are 55, 57, 82, 115, 116, 117, 118, 122, 124, 125, 127, 129, 130, 143, 144, though I fully encourage the reader to watch all of the videos because he led a fascinating life.
If you decided to skip the videos, then you may not know what the name WI-38 means.
The cell line was developed while Dr. Hayflick worked at the Wistar Institute (WI), and the number tells us how many came before it. Some of the previous cell lines simply were not successful, and in this case a fire destroyed many as well.
Dr. Stanley Plotkin also worked at the Wistar Institute at the same time as Dr. Hayflick and utilized Dr. Hayflick’s work in cell cultures to start developing the current rubella vaccine.
Human cell lines are used for developing human virus vaccines.
The full list for vaccines developed on human cells that are licensed for the USA can be found here: http://www.cdc.gov/vaccines/pubs/pinkbook/downloads/appendices/B/excipient-table-2.pdf
Many times if a vaccine is approved in the USA it will also be licensed in Canada.
The exact product monographs for Canadian vaccines can be found in the Drug Product Database (DPD), using the search tips they advise can be very useful.
It was more challenging finding clear tables for vaccine excipients for the UK, however the University of Oxford does have an entire website dedicated to vaccines titled:
Vaccine knowledge project with an article on the ingredients.
There is no tidy excipient (ingredient) table for Australia, however you can look up the package inserts by simply typing “product name package insert”. All of the licensed Australian vaccines can be found in the Australian Immunisation Handbook, section 4.
The moral and ethical considerations cannot be covered effectively in a written piece like this. As such each individual will need to determine where they stand morally, and ethically on the use of human cell lines used for vaccine manufacture. An article published in Nature did attempt to address the matter; http://www.nature.com/news/a-culture-of-consent-1.13262
The Hayflick Limit does mean that at some point in the future, new tissue will be required to create new cell lines. Indeed there was a rapid realization of this, a paper published in 1978, titled “Comparison of WI-38, MRC-5, and IMR-90 cell strains for isolation of viruses from clinical specimens”, compared cell lines for potential candidates in replacing WI-38.
Other current human cell lines used in vaccine manufacture and research include MRC-5, IMR-90, and many more. It is imperative that I clarify most cell lines are used for research and do not come from aborted foetuses.
MRC-5 was also developed in the 1960’s by J. P. Jacobs with the intention of creating a similar cell line to WI-38. Dr. Jacobs and his co-authors sent a very brief letter to Nature Publishing Group pertaining to the development of MRC-5 titled: “Characteristics of a Human Diploid Cell Designated MRC-5”.
“The stability and integrity of the human foetal cell strain WI-38, which has been well demonstrated in the past ten years, and its susceptibility to viruses infective for man, explain the value of such material for the isolation of viruses and in the development of vaccines. We have developed another strain of cells, also derived from foetal lung tissue, taken from a 14-week male foetus removed for psychiatric reasons from a 27 year old woman with a genetically normal family history and no sign of neoplastic disease both at abortion and for at least three years afterwards. The criteria used for characterizing the cells are those recommended internationally.”
IMR-90 was developed after the previous 2, and is being used to research new vaccines. The primary vaccine that comes up, is one being developed for Clostridium Difficile Toxoid.
C. difficile is defined by MedLinePlus as “This infection is a common cause of diarrhea after antibiotic use.”
Patient.co.uk has a full write up on it as well; “Infection with Clostridium difficile most commonly occurs in people who have recently had a course of antibiotics and are in hospital. Symptoms can range from mild diarrhoea to a life-threatening inflammation of the bowel. No treatment may be needed in mild cases except drinking plenty of fluids. However, treatment with specific antibiotics is needed in more severe cases.”
This cell line is not in any of the currently licensed vaccines for north america.
Large catalogues of human and animal cell lines are kept all over the world, one can be found here, the DSMZ catalogue is searchable. The Cell Line Data Base: structure and recent improvements towards molecular authentication of human cell lines paper can go into some more depth on these catalogues.
Only viral vaccines are grown using human or animal cell lines. Bacteria do not require a host cell to replicate. After the virus is isolated the cell tissue is filtered out and is technically not present in the finished vaccine.
However, there are frequently various contaminants in any vaccine (bacterial or viral), so it is possible that some tissue can remain in any given batch. The potential implications for viral mutation and recombinant viruses, or epigenetics have not been explored in any depth and what little that has been done is not giving any new selling points. Autism rates have been sky-rocketing since 1988, Dr. Deisher conducted a study to examine a possible connection between vaccines produced using human cell lines and autism titled “Impact of environmental factors on the prevalence of autistic disorder after 1979”. Sound Choice Pharmaceutical, where Dr. Deisher works also did a press release after the paper was published. In this press release Dr. Deisher is quoted as saying
“There are a large number of publications about the presence of HERV (human endogenous retrovirus - the only re-activatable endogenous retrovirus) and its association with childhood lymphoma," noted Dr Deisher. "The MMR II and chickenpox vaccines and indeed all vaccines that were propagated or manufactured using the fetal cell line WI-38 are contaminated with this retrovirus. And both parents and physicians have a right to know this!” This statement must be considered as still needing more studies to further prove or disprove her results.
This adds another point to consider regarding contaminants; human retroviruses. You can access an older textbook on retroviruses here. It is essential that studies on the potential implications of these things are conducted if the health and welfare of future generations is to be secured. You can read more on the history of human cell lines in a paper titled “A brief history of human diploid cell strains” and the guideline document titled “Derivation and characterization of cell substrates used for production of biotechnological/biological products” can also be interesting if you like really getting into finer details.