Typical Vaccine Ingredients Explained

Written by Dr Steven L. Robertson on September 29, 2025. Posted in Current News

Vaccines are one of the most heatedly discussed medical topics today, and there’s often confusion about what they actually contain

Some people worry about “aborted fetal cells” or chemicals like mercury and aluminum.

As a physician I was asked countless times about vaccines, to which my canned response was, ‘lots of research and staunch opinions for them and against them..but at the end of the day you are putting your baby to bed so that’s a question for you and your family to decide.’

So let’s break it down.

Fetal Cell Lines: What They Are and Are Not

• Fetal cell lines are special cell cultures that scientists grow in laboratories.
• They were originally created decades ago (1960s–1980s) from tissue obtained after elective abortions.
• Commonly used cell lines include:
  • WI-38 (fetal lung, 1962)
  • MRC-5 (fetal lung, 1966)
  • HEK 293 (fetal kidney, 1973)
  • PER.C6 (fetal retina, 1985)

These cells are not “new fetal tissue.” They are many generations removed and have been grown in labs for decades.

Important: Vaccines do not contain fetal cells. Instead, certain viruses are grown in these cells during production, and then the vaccine is purified. Very tiny DNA fragments may remain, but not intact cells.

Here’s a list of Vaccines That Have Used Fetal Cell Lines in case you feel like you’re running low on fetal cell line DNA fragments.

Some vaccines have historically used these human cell lines in their development or production:

• MMR (Rubella component) – WI-38 or MRC-5
• Varicella (Chickenpox) – MRC-5
• Hepatitis A (Havrix, Vaqta, Twinrix) – MRC-5
• Shingles (Zostavax, older version) – MRC-5
• Rabies (Imovax, some versions) – MRC-5
• COVID-19 vaccines
  • Pfizer & Moderna: tested using HEK 293, not produced in them.
  • Johnson & Johnson / AstraZeneca: produced using HEK 293 or PER.C6.

Most other vaccines are produced in chicken eggs, yeast, or other cell cultures.

Common Ingredients in Vaccines

Vaccines typically contain more than just the virus (or viral protein). To ensure effectiveness and stability, they may include:

1. Adjuvants

• Aluminum salts (aluminum hydroxide, aluminum phosphate, aluminum potassium sulfate)← look those up 👀
  • Used in vaccines like DTaP, hepatitis A & B, HPV, pneumococcal.
  • Helps the body create a stronger, longer-lasting immune response. 🧐

2. Preservatives (prevent contamination)

• Thimerosal (a mercury-containing compound)👀
  • Once common in multi-dose vials of vaccines.
  • Removed or reduced to trace amounts in nearly all U.S. childhood vaccines since the early 2000s.
  • Still used in some multi-dose flu vaccines….

3. Stabilizers

• Sugars (sucrose, lactose)
• Gelatin (often from pork)
• Proteins (such as human serum albumin or bovine serum albumin)

4. Residuals from the manufacturing process

• Egg protein (in flu vaccines grown in chicken eggs)
• Yeast proteins (in vaccines made using yeast, like HPV and Hepatitis B)
• Cell culture material (tiny DNA/protein traces from human or animal cell lines used to grow viruses)

5. Other components

• Formaldehyde
• Antibiotics

So vaccines do not contain whole fetal cells. Some have been researched, developed, or produced using fetal-derived cell lines and yes dna is left in small amounts. Another way of looking at that is it’s usually a small human that’s getting injected.

• Actual vaccine ingredients typically include adjuvants (like aluminum salts), preservatives (like thimerosal in some multi-dose vials), stabilizers, and trace residuals from the manufacturing process.
• Most vaccines today are produced using chicken eggs, yeast, or other cultures rather than human cell lines.

History

Here’s the background of the abbreviations and which aborted fetuses these cells originated from…you’d think the Churches would have something to say about this but then again most are given government funding to support and follow the party line (and that’s left and right).

HEK 293

• Name meaning: “HEK” = Human Embryonic Kidney, 293 = the 293rd experiment performed by the scientist (Dr. Frank Graham, 1973).
• Origin: Kidney cells from a female fetus aborted in the Netherlands in 1973.
• Use: Used in biotechnology and medical research, including testing and production of some COVID-19 vaccines.

PER.C6

• Name meaning: Derived from “PER” = Per.C6 designation by Crucell (a Dutch company).
• Origin: Retinal cells from an 18-week fetus, elective abortion in 1985 in the Netherlands.
• Use: Used in gene therapy, monoclonal antibody production, and in some vaccine platforms (e.g., Johnson & Johnson COVID-19 vaccine).

MRC-5

Medical Research Council — 5 (the fifth cell culture developed by that team).

• Origin / year: Derived in 1966 at the UK Medical Research Council (National Institute for Medical Research).
• Fetus details / tissue: Lung tissue from a 14-week fetus (elective abortion).
• Cell type / properties: Human diploid fetal lung fibroblast cell strain (a finite cell strain, not an immortal cell line).
• Used in: Historically used to grow viruses for vaccine development and production — examples include Hepatitis A, Varicella (chickenpox), older Zostavax (shingles), and some rabies vaccines, among other research uses.
• WI-38 & MRC-5 = fetal lung cell lines from the 1960s → used in rubella, chickenpox, Hepatitis A, and some rabies/shingles vaccines.
• HEK 293 & PER.C6 = kidney/retina cell lines from the 1970s–1980s → widely used in biotech research and certain COVID-19 vaccines.

Thanks for taking the time to go through this article as it’s not always easy to dig into details like these, but your effort to learn and educate yourself is something worth applauding and your future generations will appreciate your knowledge.

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