Post by LymeEnigma on Sept 14, 2008 15:20:12 GMT -8
INFECTION AND IMMUNITY,
0019-9567/97/$04.0010
Jan. 1997, p. 285–292 Vol. 65, No. 1
Copyright q 1997, American Society for Microbiology
Arthritis Severity and Spirochete Burden Are Determined by Serotype
in the Borrelia turicatae-Mouse Model of Lyme Disease
PAMELA M. PENNINGTON,1 CRAIG D. ALLRED,2 CASEY S. WEST,1 RENE ALVAREZ,1
AND ALAN G. BARBOUR1*
Departments of Microbiology and Medicine1 and Department of Pathology,2 University of Texas
Health Science Center, San Antonio, Texas 78284
Received 14 August 1996/Returned for modification 19 August 1996/Accepted 23 October 1996
Immunodeficient mice infected with Borrelia turicatae, a relapsing fever agent, have a disorder that resembles
disseminated Lyme disease. Two serotypes, A and B, differed in their arthritogenicity in both CB-17 SCID and
C3H SCID mice. In CB-17 SCID mice infected with serotype A or B, arthritis was assessed by measurement
of tibiotarsal diameter, functional ability on a beam walk test, and microscopic assessment of joint inflammation.
Serotype B-infected mice had greater joint swelling, functional disability, and leukocytic infiltration in
the joints than serotype A-infected mice. Joint swelling and disability peaked at 2 weeks of infection and then
decreased, while leukocyte infiltration in the joints persisted. To investigate the basis for the differences in
arthritogenicity of serotypes A and B, spirochete burdens in infected mice were measured by quantitative PCR
of spirochete DNA in joints, direct immunofluorescence of spirochetes in joints, and counts of spirochetes in
the blood. At 2 weeks of infection there were seven times more spirochetes in the joints of serotype B-infected
mice than in those of serotype A-infected mice, measured by both quantitative PCR and direct enumeration.
Although serotypes A and B had the same infectivity and growth rate in vivo, serotype B spirochetes were
eightfold more abundant in the blood than serotype A spirochetes and produced greater fatality in newborn
mice. These findings indicate that differences in disease severity in mice infected with serotype A or B are
attributable to differences in the spirochete burden in the joints and blood.
Full article: iai.asm.org/cgi/reprint/65/1/285?view=long&pmid=8975925
0019-9567/97/$04.0010
Jan. 1997, p. 285–292 Vol. 65, No. 1
Copyright q 1997, American Society for Microbiology
Arthritis Severity and Spirochete Burden Are Determined by Serotype
in the Borrelia turicatae-Mouse Model of Lyme Disease
PAMELA M. PENNINGTON,1 CRAIG D. ALLRED,2 CASEY S. WEST,1 RENE ALVAREZ,1
AND ALAN G. BARBOUR1*
Departments of Microbiology and Medicine1 and Department of Pathology,2 University of Texas
Health Science Center, San Antonio, Texas 78284
Received 14 August 1996/Returned for modification 19 August 1996/Accepted 23 October 1996
Immunodeficient mice infected with Borrelia turicatae, a relapsing fever agent, have a disorder that resembles
disseminated Lyme disease. Two serotypes, A and B, differed in their arthritogenicity in both CB-17 SCID and
C3H SCID mice. In CB-17 SCID mice infected with serotype A or B, arthritis was assessed by measurement
of tibiotarsal diameter, functional ability on a beam walk test, and microscopic assessment of joint inflammation.
Serotype B-infected mice had greater joint swelling, functional disability, and leukocytic infiltration in
the joints than serotype A-infected mice. Joint swelling and disability peaked at 2 weeks of infection and then
decreased, while leukocyte infiltration in the joints persisted. To investigate the basis for the differences in
arthritogenicity of serotypes A and B, spirochete burdens in infected mice were measured by quantitative PCR
of spirochete DNA in joints, direct immunofluorescence of spirochetes in joints, and counts of spirochetes in
the blood. At 2 weeks of infection there were seven times more spirochetes in the joints of serotype B-infected
mice than in those of serotype A-infected mice, measured by both quantitative PCR and direct enumeration.
Although serotypes A and B had the same infectivity and growth rate in vivo, serotype B spirochetes were
eightfold more abundant in the blood than serotype A spirochetes and produced greater fatality in newborn
mice. These findings indicate that differences in disease severity in mice infected with serotype A or B are
attributable to differences in the spirochete burden in the joints and blood.
Full article: iai.asm.org/cgi/reprint/65/1/285?view=long&pmid=8975925