Human innate-defense peptide; alpha-defensin
Alpha-defensin 1
Alpha-defensin 1, also called HNP-1, is a human neutrophil peptide. It should be distinguished from HNP-2, HNP-3 and preparations containing the HNP-1–3 mixture.
This is a research reference, not a product offered in the Asciende catalog. Published studies do not establish the identity, purity or availability of a commercial preparation.
Activity in a model and assay conditions
Separate result and explanation. Activity under particular conditions does not define a specification for every material using the same name.
- Does the observation come from a cellular system, microorganism or whole organism?
- Are vehicle, medium and controls that may change the readout reported?
- Does the observed marker demonstrate the proposed mechanism or merely remain compatible with it?
Mechanism described in the literature
Purified HNP-1 showed in vitro microbicidal activity comparable to that of the mixture in the cited experiments. A survival readout demonstrates a functional response, but does not identify a unique molecular target.
Other names in the literature
- HNP-1
- Human neutrophil peptide 1
Closely related sequences remain distinct identities
Structural characterization identified amino-terminal differences among HNP-1, HNP-2 and HNP-3. Similarity across the remaining chain does not make findings automatically transferable among the three peptides. The identity of the purified material remains part of the interpretation (PMID 4056036).
A mixture is not an exhaustive characterization of one component
Responses to the HNP-1–3 mixture depended on the microorganism and nutrient conditions. The original work also examined individual defensins, but conditions established for a mixture do not exhaustively characterize HNP-1 by itself (PMID 2997278).
Localization and individual quantification answer different questions
Granular staining of neutrophils with reagents recognizing HNP-1–3 locates the group. It does not necessarily quantify HNP-1 individually. Interpretation depends on whether the antibody discriminates among individual peptides or detects a shared family signal.
Questions and answers
Is HNP-1–3 another name for HNP-1?
No. HNP-1–3 denotes a mixture of three peptides; HNP-1 identifies one component. Their experimental results should remain separately attributed.
Does a microbicidal response establish a unique target?
No. A functional survival assay requires additional mechanistic evidence before the response can be assigned to a specific molecular target.