Protective outcomes of high-affinity monoclonal antibodies against drug-resistant plague strains

To evaluate the protective efficacy of monoclonal antibodies (mAbs) against drug-resistant strains of Yersinia pestis.

At a dosage of 100 µg, mAbs Fm3 and Fm25 provided 100% protection against Y. pestis strain 141.
At a dosage of 20 µg, Fm3 showed partial protection with a 25% survival rate, while all mice at 4 µg died within approximately 10 days.
Fm25 at 100 µg resulted in total survival against the drug-resistant strain S19960127, while Fm3 provided 75% protection at the same dosage.

The study indicates that mAbs Fm3 and Fm25 may offer protection against both virulent and drug-resistant variants of Y. pestis.

The study primarily focused on mouse models, which may not fully replicate human responses.
The efficacy of mAbs at lower dosages was not demonstrated.

Fm3 and Fm25 may serve as candidates for further investigation in therapeutic strategies against drug-resistant Y. pestis infections.