Cysteine-rich secretory proteins (CRISPs) represent a family of evolutionarily conserved proteins that may play a role in the innate immune system and are transcriptionally regulated by androgens in several tissues. CRISP proteins are highly expressed in the mammalian reproductive tract and in the venom secretory ducts of some reptiles. CRISP-11 (cysteine-rich secretory protein 11), also known as cysteine-rich secretory protein LCCL domain-containing 2 (CRISPLD2 or LCRISP2), is a 497 amino acid protein containing 2 LCCL domains, which are thought to function as autonomous folding domains used to construct modular proteins through exon shuffling. Serum concentrations of CRISP-11 have been shown to be an indicator of a patient’s exposure to lipopolysaccahride (LPS), the immunostimulatory component of Gram-negative bacteria, and can determine one’s sensitivity to it.