Expression and characterization of recombinant interferon gamma (IFN-gamma) from the nine-banded armadillo (Dasypus novemcinctus) and its effect on Mycobacterium leprae-infected macrophages.
Armadillos (Dasypus novemcinctus) manifest the full histopathological spectrum of leprosy, and are hosts of choice for in vivo propagation of Mycobacterium leprae. Though potentially useful as a model of leprosy pathogenesis, few armadillo-specific reagents exist. We have identified a region of high homology to the interferon gamma (IFN-gamma) of other mammals within the recently published armadillo whole genomic sequence. cDNA was made from ConA-stimulated armadillo peripheral blood mononuclear cells (PBMC), amplified, and cloned into a pET expression vector for transformation and over-expression in Escherichia coli. The recombinant protein (rDnIFN-gamma) was characterized by western blot and its biological function confirmed with bioassays including intracellular killing of Toxoplasma gondii and induction of indoleamine 2, 3-dioxygenase activity. In using rIFN-gamma to activate macrophages from mice, humans or armadillos, similar to humans, rIFN-gamma-activated armadillo MPhi did not produce nitrite and or inhibit the viability of M. leprae in vitro. Conversely, murine rIFN-gamma-activated mouse MPhi produced high levels of nitrite and killed intracellular M. leprae in vitro. These data indicate that the response of armadillo MPhi to rDnIFN-gamma is similar to that which occurs in humans, and demonstrates a potentially important value of the armadillo as a model in leprosy research.
Peña
M T
MT
DHHS/HRSA/BPHC, National Hansen's Disease Program, LSU School of Veterinary Medicine, Microbiology Research Department, Skip Bertman Drive, Baton Rouge, LA 70803, USA.
Adams
J E
JE
Adams
L B
LB
Gillis
T P
TP
Williams
D L
DL
Spencer
J S
JS
Krahenbuhl
J L
JL
Truman
R W
RW
D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000276:immunology; D001135:Armadillos / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D049109:Cell Proliferation / Q000187:drug effects; D018076:DNA, Complementary / Q000235:genetics; D015870:Gene Expression; D006801:Humans; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase / Q000378:metabolism; D007371:Interferon-gamma / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology*; D008264:Macrophages / Q000166:cytology / Q000187:drug effects*; D008969:Molecular Sequence Data; D009166:Mycobacterium leprae / Q000502:physiology*; D009573:Nitrites / Q000378:metabolism; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D011994:Recombinant Proteins; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D000906:Antibodies; D018076:DNA, Complementary; D050503:Indoleamine-Pyrrole 2,3,-Dioxygenase; D009573:Nitrites; D020033:Protein Isoforms; D011994:Recombinant Proteins; D007371:Interferon-gamma