Loading ...Is destroying the immune system using the tolerance built up over time of being exposed to something like bee stings or chronic pain meds to block or calm the immune system to respond when needed by increasing the levels of IgG4…
Pfizer Vaccine Triggers MORE IgG4 Than Moderna But WHY?What the Latest Research on IgG4 Class Switching Reveals About the mRNA Vaccines
Every time we think we’ve unraveled the complexities of the immune response to COVID-19 vaccines, new data emerges that forces a reevaluation. This week, a new study published on July 16th, 2025, did exactly that—highlighting a striking difference between the Pfizer (BNT162b2) and Moderna (mRNA-1273) vaccines in how they influence antibody class switching. Once again, the focus is on IgG4—an antibody subclass typically associated with immune tolerance, not immune activation. We see IgG4 in beekeepers, for instance, who develop tolerance after repeated stings. It’s a protective adaptation that prevents overreaction to repeated exposure. But what happens when that tolerance mechanism is applied to a virus like SARS-CoV-2, which the body needs to clear, not ignore? The Study’s Findings: Pfizer Induces More IgG4This latest research compared immune responses in individuals boosted with either Pfizer or Moderna. The key finding?
That surprised many of us. Moderna uses more mRNA (100 µg vs. Pfizer’s 30 µg)—so logically, one might expect it to cause more immune tolerance. But it didn’t. The IgG4 response was markedly higher in the Pfizer group. So why would a lower-dose vaccine lead to more immune tolerance? Siebner, Alex S., et al. “Class switch towards IgG2 and IgG4 is more pronounced in BNT162b2 compared to mRNA-1273 COVID-19 vaccinees.” International Journal of Infectious Diseases. The Molecular Detail That May Hold the AnswerDigging deeper into the vaccine design reveals a crucial difference: the 5′ untranslated region (UTR) of the mRNA.
This 5′ UTR acts as a “start signal” for the ribosome, guiding how spike protein is produced. The theory is that Pfizer’s globin UTR enables longer-lasting, lower-intensity spike protein expression. Over time, this prolonged exposure may nudge the immune system into a tolerogenic state, increasing IgG4 production. It’s a small molecular detail—but one with large immunological consequences.
Why Does This Matter?Earlier studies have already shown that repeated mRNA vaccination can lead to IgG4 making up as much as 45% of the antibody profile, compared to just 1% after natural infection. This latest paper adds that Pfizer’s formulation may be driving this shift even more strongly than Moderna’s.
Why? Because IgG4 is non-inflammatory. It blocks rather than destroys. Your immune system stops treating the spike protein as a threat—and starts tolerating it. Could Spike Protein Persist as a Result?That leads to the next question: If the body becomes tolerant, could the spike protein linger? A growing body of data suggests that in some individuals, spike protein can still be detected in the blood nearly two years after vaccination. This isn’t true for everyone—but it’s true for enough people to raise serious concerns. The implication is that Pfizer’s vaccine design may be promoting a form of long-term antigen exposure, coupled with a muted immune response. That’s a setup for chronic immune confusion—or worse, immune exhaustion. |
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