Inflammatory polyarthritis in mice transgenic for human T cell leukemia virus type I.
OBJECTIVE
We have recently reported that arthropathy develops in high incidence among transgenic mice carrying the pX region of human T cell leukemia virus type I (HTLV-I). In the present study, the histopathologic features of the joints in these mice were examined in order to compare the animal disease with rheumatoid arthritis (RA) in humans.


METHODS
Paraffin sections of limbs (right and left fingers, wrists, elbows, shoulders, toes, knees, and ankles) were stained with hematoxylin and eosin, periodic acid-Schiff, azan-Mallory, or phosphotungstic acid hematoxylin, and examined by light microscopy.


RESULTS
Abnormalities of the limbs began to occur as early as 3 weeks of age, and the incidence gradually increased until the mice were 12 months old. The incidence of arthropathy was 22% (48 of 217) at 3 months of age and 28% (18 of 64) at 6 months. The severity of the histopathologic changes in the joints of the transgenic mice ranged from grade I to grade IV.


CONCLUSIONS
The major histopathologic features in the joints of HTLV-I transgenic mice are similar to those in humans with RA. Thus, these mice may represent a useful model for the study of the disease in humans.
Yamamoto
H
H
Laboratory of Experimental Pathology, Kohno Clinical Medicine Research Institute, Tokyo, Japan.
Sekiguchi
T
T
Itagaki
K
K
Saijo
S
S
Iwakura
Y
Y
D000818:Animals; D001168:Arthritis / Q000209:etiology* / Q000473:pathology; D001808:Blood Vessels / Q000473:pathology; D015368:Human T-lymphotropic virus 1 / Q000235:genetics*; D007596:Joints / Q000098:blood supply / Q000382:microbiology / Q000473:pathology; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D013583:Synovial Membrane / Q000473:pathology