Table 1.

Summary of host defense functions examined for RNase A family ribonucleases.

RNase A Ribonuclease	Species	PI	Host Defense Activities
Eosinophil-derived neurotoxin (RNase 2)	Human	9.0	Chemoattractant for immature human dendritic cells [2].
			Enhances maturation of dendritic cells [3]1
			Reduces infectivity for RNA viruses (HRSV, HIV) in tissue culture assays [4 - 6]2
			Produced in macrophages in response to LPS and TNF-α [3]
			Activates TLR2 and augments Th2 biased immune responses [7]
Eosinophil cationic protein (RNase 3)	Human	10.8	Cytotoxin for helminthes [8 -14], strong bactericidal activity [15]
			Reduces infectivity for HRSV in tissue culture assay [16]
Eosinophil-associated RNase 2	Mouse	9.70	Chemoattractant for immature human dendritic cells [2]
Eosinophil-associated RNase 11	Mouse	9.10	Produced by alveolar macrophages in response to Th2 cytokine stimulation [17]
			Produced in response to respiratory virus infection, up-regulated in the absence of type I interferon signaling [18]
Eosinophil-associated RNases 1 and 2	Rat	8.6	Moderate bactericidal activity against E. coli and S. aureus [19, 20]
Angiogenin (RNase 5)	Human	10.1	Moderate bactericidal activity against S. pneumoniae [21]; conflicting report [22]
Angiogenin-4	Mouse	9.0	Moderate bactericidal activity against L. monocytogenes and E. faecalis [21]
			Produced in response to bacterial LPS [21].
RNase 7	Human	10.3	Broad spectrum strong bactericidal activity, very strong against E.faecium [23]
RNase 8	Human	8.4	Broad spectrum moderate bactericidal activity [24]
Leukocyte RNase A-2	Chicken	10.9	Bactericidal against E. coli, S. aureus [25] and Salmonella sps. (unpublished data)
Dr-RNases 1, 2, and 3	zebrafish	9.0, 9.2, 8.8	Broad spectrum moderate bactericidal activity against E. coli [26]

Values for isoelectric point (pI) are calculated based on primary amino acid sequences. Moderate bactericidal activity, low micromolar concentrations in standard overnight incubation assay reduce colony count 10 - 100 fold; strong bactericidal activity, low micromolar concentrations reduce colony count 10⁴ to 10⁷ fold.

¹Activity also shared with human pancreatic ribonuclease, or RNase 1,

²Activity dependent on enzymatic (ribonuclease) activity.