Related Experiment Video
Updated: Jul 11, 2026

Induction of Paralysis and Visual System Injury in Mice by T Cells Specific for Neuromyelitis Optica Autoantigen Aquaporin-4
Published on: August 21, 2017
Delayed allergic reaction to natalizumab associated with early formation of neutralizing antibodies
Markus Krumbholz1, Hannah Pellkofer, Ralf Gold
1Institute for Clinical Neuroimmunology, Ludwig Maximilian University, Marchioninistrasse 15, 81377 Munich, Germany. krumbholz@neuro.mpg.de
Background:
Natalizumab is a new therapeutic option for relapsing-remitting multiple sclerosis. As with other antibody therapies, hypersensitivity reactions have been observed. In the Natalizumab Safety and Efficacy in Relapsing-Remitting Multiple Sclerosis (AFFIRM) trial, infusion-related hypersensitivity reactions developed in 4% of patients, usually within 2 hours after starting the infusion.
Objective:
To report a significant, delayed, serum sickness-like, type III systemic allergic reaction to natalizumab.
Design:
Case report describing clinical follow-up and the serial measurement of antinatalizumab antibodies.
Patient:
A 23-year-old man with relapsing-remitting multiple sclerosis developed a fever, arthralgias, urticarial exanthema, and a swollen lower lip during several days after his second infusion of natalizumab.
Results:
The patient developed a delayed, serum sickness-like, type III systemic allergic reaction to natalizumab. Five weeks after initiation of this therapy, he tested positive for antinatalizumab antibodies and exhibited persistent antibody titers 8 and 12 weeks later. His symptoms completely resolved with a short course of oral glucocorticosteroids.
Conclusion:
Clinicians and patients should be alert not only to immediate but also to significantly delayed substantial allergic reactions to natalizumab.
Related Concept Videos
Drug Toxicity: Allergic Reactions
Hypersensitivity Reactions: Delayed Hypersensitivity Reactions
Development of Immunocompetence
The initial cells that migrate from the fetal thymus settle within the skin and epithelial tissues lining the mouth, digestive tract, and in females, the uterus and vagina. These cells, including skin-based dendritic cells, serve as antigen-presenting cells, playing a key role in T cell activation.
Subsequent T...
Hypersensitivity Reactions: Immune-Complex Reactions
Hypersensitivities
Types of Hypersensitivities
Hypersensitivity reactions are categorized into four types: Type 1, Type 2, Type 3, and Type 4. Each type has a distinct mechanism...
Allergic Drug Reactions

