It is far more efficient and cheaper to use human tumor cell lines – cell lines derived from human tumors many years ago – to grow vaccines.
FDA Briefing Document, Vaccines and Related Biological Products Advisory Committee Meeting September 19, 2012; a balanced summary is: 1. human cancer cell lines don’t generally form tumors in humans, 2. if they had this potential then they would still be liable to rejection by the host immune system, 3. chemicals, such as formaldehyde, are used to inactivate any potential viruses, 4. the threat remains a theoretical concern, because cell DNA could contain infectious genomes which could lead to initiation of an infection that originally led to the formation of the cancer from which the cell lines were derived. i.e unlikely that any vaccine would contain sufficient DNA from the cells in which its virus was grown to cause cancer (total cellular DNA transmitted is in the region of 10-12 grams per dose of vaccine, which is extremely low). FDA Briefing Document Vaccines and Related Biological Products Advisory Committee Meeting September 19, 2012.
HeLa cells are a common human cancer cell line derived from a woman named Henrietta Lacks, who died of cervical cancer in the 1950s. They were injected into prisoner ‘volunteers’ without reports of any subsequent malignant cancer formation; i.e. the human immune system rejected them as it would any transplant of a foreign body. Is this, then, a no-fail safety net? No, because most cancers have reduced their immunogenicity as part of their ‘survival’ mutation, and could be potentially harmful if transmitted to immunocompromised patients.
HeLa cells are unlike normal human cells. Normal human cells have 46 chromosomes, while HeLa has 76 to 80 mutated chromosomes, triggered by the human papilloma virus (HPV), the cause of nearly all cervical cancers. HPV inserts its DNA (infectious genome) into a host cell, causing it to producing a protein that inactivates the p53 protein which prevents mutations and suppresses tumors. Inactivated p53 protein is a time-bomb of cancer formation:
Many human cancers involve the inactivation of p53. Mutant p53 not only does not function as a tumor suppressor but may also exert tumor-promoting effects. Approximately half of all cancers have inactivated p53 (T. Soussi and C. Béroud, “Assessing TP53 status in human tumours to evaluate clinical outcome,” Nature Reviews Cancer, vol. 1, no. 3, pp. 233–240, 2001). This anti-cancer protein also prevents premalignant lesions from developing into malignant (K. H. Vousden and C. Prives, “Blinded by the light: the growing complexity of p53,” Cell, vol. 137, no. 3, pp. 413–431, 2009).
It is vital, therefore, that scientists are satisfied of the complete safety of introducing very small amounts of an infectious genome into a vaccine recipient.
The aforementioned FDA briefing document makes it very clear that there are strict limits on the amount of DNA allowed in each vaccine dose, and that each dose has been treated with am array of filtering and inactivation substances –
aluminium, polysorbate 80, formaldehyde, aspartame, benzethonium chloride, glutaraldehyde, thimerosal, MSG, squalene, cetyltrimethylammonium bromide and phenoxyethanol – so no problems, it’s as safe as drinking tap water.
What certainly does not give reassurance are the views of doctors given at this FDA meeting:
Dr. Pedro Piedra, Baylor College of Medicine: ‘This is much downstream, but it goes with the issue of public perception. At the end of the day, information will need to be included in the vaccine safety information and the package insert’.
Dr. Phil Krause, Acting Deputy Director of the FDA office of vaccines: I think we would have to work that out, depending on whether or not we believe there is a risk for potential induction of tumor. Listening to Dr. Gruber’s earlier comment, I think we would be very reluctant, and I’m sure manufacturers would be very reluctant, to proceed if they really thought there was a significant risk of a potential induction of a tumor. Normally the package inserts describe ingredients in products which are safety factors, that have some role in assessing the safety of the product. So I can’t answer your question directly, because it will depend on that final assessment. But the hope would be that if one could proceed with these cells, one would have addressed those issues’.
Dr. Marion Gruber, Acting director of the FDA office of vaccines: I would like add to this …it goes back to the earlier point I made — I think the minute that we think that we have to address any of these concerns in the clinic, — we would be very reluctant for a cell substrate such as these cells to be used for vaccine production, if we are not reasonably assured that the characterization done, as we have discussed today, is adequate. The minute you describe something in the package insert in terms of potential clinical safety concerns, I think that really precludes using these cell substrates’.
Put very simply, if we believe our studies, and are reasonably assured such vaccines are safe, then there is no need to inform the public of details that may effect vaccine uptake (manufacturers profit).
Thus, it all boils down to how much weight can be given to the US Centres for Disease Control (CDC) being reasonably assured about the safety of human cancer cell lines in manufacturing vaccines.
The CDC, between 1989-1991, used high potency Edmonston-Zagreb measles vaccine as a test on 1,500 impoverished children in Los Angeles. The World Health Organisation (WHO) had previously injected this vaccine into children in Mexico, Haiti, and Africa. The vaccine was withdrawn in 1992 when it was found that it caused long-term suppression of the children’s immune system, and these children died from other diseases in greater numbers than children who had not received the vaccine.
The CDC and WHO were ‘reasonably assured‘ about the safety of this vaccine.
How vigourously had it been tested?
Was it tested totally independently of its manufacturers?
What percentage equates to ‘reasonably assured‘? 70%? 80%? 95%? 99.9%?
Vital questions, obviously, for, if scientists are wrong again, the downstream effect of a mass-scale inactivation of the human immune system will be devastating.
lenin nightingale 2015