Members of this family include: These proteins consist of N- and C-terminal domains, which share a similar two-layer alpha/beta structure, but show little sequence identity to each other.

[4] The fold contains apolar binding pockets that can interact with hydrophobic and amphipathic molecules, such as the acyl carbon chains of lipopolysaccharide found on Gram-negative bacteria.

PLUNC appears to be a secreted product of neutrophil granules that participates in an aspect of the inflammatory response that contributes to host defence.

[11] Bacterial permeability family member A1 (BPIFA1/SPLUNC1) is an innate protein that is secreted basolaterally from healthy, but not asthmatic, human bronchial epithelial cultures (HBECs).

It suppresses airway smooth muscle contractility by binding to and inhibiting the Ca2+ influx channel Orai1.