| Effector Molecule |
Source |
Activity |
Target Organisms |
| Lysozyme
13 µg/mL in vaginal fluid, 1 mg/mL in mucus plug [92] |
Secreted by serous cells in submucosal glands [11] |
Cleaves bonds in peptidoglycan component of cell walls, cationic disruption of microbial membranes [93] |
Gram-negative bacteria [93]
Weak at normal concentrations against bacteria, some antiviral (HIV) [94] |
Lactoferrin
1 µg/mL in vaginal fluid, 100 µg/mL in cervical plug [92] |
Secreted by serous cells in submucosal glands [11]* |
Sequesters iron, also disrupts microbial membranes [11]
Inhibits cellular fusion and entry by virus [95] |
Gram negative bacteria [93] , virus [95] |
Calprotectin
34 µg/mL [11] |
Component of neutrophils, monocytes and keratinocytes [95] |
Sequesters zinc [11] |
Inhibits growth of fungi and yeast [96] |
| Human Alpha Defensins HPN 1,2,3,4
about 2 µg/mL [59] |
Synthesized in bone marrow [97] |
Comprise contents of phagocytic vacuoles that effect microbicidal activity [98]
increase the production of TNF and IL-1 |
Bacteria, fungi, viruses [11] |
5 HD5
10 to 40 ng/mL |
Columnar epithelium of endocervix [99] |
Binds electrostatically to negatively charged microbial particle, forming pores in cell membrane and eventually causing lysis [100] |
Bacteria, fungi, viruses [11] |
| Human Beta Defensins |
vaginal epithelial cells leukocytes [11]
HBD‑1 is produced constitutively in mucosa [11]
Human defensins HBD2 and 3 are induced at inflamed sites [11] |
Antimicrobial activity, inhibition of HIV-infectivity of immunocompetent cells, chemoattraction of T cells immature dendritic cells B cells neutrophils and macrophages [101,102] |
Gram-positive or Gram- negative bacteria, mycobacteria. yeast, enveloped viruses viral (in vitro) [103] |
SLPI
10 to 100 µg/mL in vaginal secretions, as high as 1000 µg/mL in cervical mucus plug [11] |
Found in epithelial secretions, also produced by macrophages [11] |
Blocks action of hostile enzymes released by invading organisms [3] Suppresses central transcription factor of inflammatory response [104] |
Bacteria and fungi (weak at normal concentrations) [11]
Antiviral (HIV-1) [61] |
| Surfactin Protein A |
In vaginal secretions [105, 106] |
Facilitates phagocytosis of microbes, increases chemotaxis, increases oxidative burst by phagocytes, modulates pro- inflammatory cytokine production by immune cells [105- 107] |
Bacteria, viruses [105, 106] |
| Surfactin Protein D |
In vaginal secretions [108] |
Increases permeability of bacterial cell membranes [107]
stimulates oxygen radical release, contributing to destruction of virus [109] |
Bacteria [107], viruses [108] |
| MBL |
Transudate from liver |
Facilitates complement activation and opsonization by binding to pathogenic microbes [63] |
|
| Elafin |
Epithelial cells |
Antimicrobial , inhibits inflammation-related tissue damage by blocking elastase [3] |
|
Cathelicidin (LL-37)
1 µg/mL[11] |
Components of neutrophils[11] |
Postcoital processing from hCAP18 precursor to functional form, targeting specifically microbes which may have been introduced by intercourse [110] |
Bacteria and fungi [11] |
