Is the Meningococcal polysaccharide (MPSV4) vaccine associated with mast cell activation?

MPSV4 and Mast Cell Activation: Literature Review

Direct Answer

There is no published literature establishing an association between the meningococcal polysaccharide vaccine (MPSV4) and mast cell activation. The available guidelines and research focus on standard contraindications—specifically severe allergic reactions to vaccine components or dry natural rubber latex—but do not identify mast cell activation disorders as a recognized adverse effect or contraindication 1.

Evidence from Guidelines

The Advisory Committee on Immunization Practices (ACIP) guidelines comprehensively address MPSV4 contraindications and precautions but make no mention of mast cell activation 1:

• The only absolute contraindication is a known severe allergic reaction to any vaccine component, including dry natural rubber latex 1
• Vaccination should be deferred for moderate or severe acute illness until clinical improvement, but minor acute illnesses (diarrhea, mild upper respiratory infections with or without fever) are not contraindications 1
• MPSV4 can be safely administered to immunosuppressed individuals, though immune response may be suboptimal 1

Safety Profile in Clinical Trials

Research studies evaluating MPSV4 safety have not reported mast cell activation as an adverse event 2, 3:

• In controlled trials comparing conjugate vaccines to MPSV4, local reactions occurred in 60-62% and systemic reactions in 46-59% of MPSV4 recipients, with no mention of mast cell-mediated reactions 2
• Historical field trials in epidemic settings (21,640 vaccinated individuals) documented excellent safety profiles without reports of mast cell activation 3

Clinical Context

The absence of literature does not mean the association cannot exist in individual cases, but it indicates:

• Mast cell activation has not been recognized as a pattern in post-marketing surveillance systems like VAERS 1
• No mechanistic studies have investigated polysaccharide vaccines as mast cell triggers
• Standard allergy precautions (screening for severe allergic reactions to components) remain the primary safety consideration 1

Practical Approach for Patients with Mast Cell Disorders

In the absence of specific guidance, exercise clinical caution:

• Screen for prior severe allergic reactions to vaccine components or latex before administering MPSV4 1
• Consider using MenACWY conjugate vaccines instead when age-appropriate (ages 2-55 years), as they may have different immunologic profiles 1
• For adults ≥56 years requiring single-dose vaccination where MPSV4 is preferred, weigh individual risk factors 1
• Ensure appropriate monitoring and emergency equipment availability as with any vaccination in patients with known allergic or mast cell disorders 1

Important Caveats

• MPSV4 is increasingly being replaced by conjugate vaccines (MenACWY) in most age groups due to superior immunogenicity and duration of protection 1, 4
• MPSV4 remains the only licensed option for adults >55 years, though MenACWY may be used off-label in certain high-risk situations 1
• The polysaccharide vaccine can induce immunologic hyporesponsiveness with repeated doses, which is a separate concern from mast cell activation 1, 4