099 inhibitory effect on arterial injury
TRANSCRIPT
Inhibitory effect on arterial injury-induced neointimal formation by adoptive B cell transfer in Rag-1 KO mice
P. Dimayuga, B. Cercek, S. Oguchi, G. N. Fredrikson,J. Yano, P. K. Shah, S. Jovinge, J. Nilsson
Department of Medicine, Lund University, University Hospital MAS, Malmö, Sweden Atherosclerosis Research Center, Cedars-Sinai Medical Center, Los Angeles, California;
Department of Biomedical Laboratory Science, Health and Society, Malmö University, Malmö, Sweden
General Findings:
• Immune-deficiency results in increased neointimal formation after arterial injury in mice.
• Humoral aspects of the immune system may be involved in inhibiting neointimal formation:
B cells produce “natural antibodies” ?
Background•T cell deficiency results in increased neointima in injured rats (antibodies against T cell CD markers and nu/nu rats)
Hansson, et al PNAS/Circ 1991 Remskar et al Circ Res. 2001
•CD40-CD40 ligand interaction mediates response to arterial injury
Remskar et al Circ Res. 2001
•B cells implicated in bone-healing response as a limiting factor
Marusic, et al LI 2000
•Homologous oxLDL immunization reduces neointimal formation in injured hypercholesterolemic rabbits
Nilsson et al JACC 1997
Arterial Injury
Activation of signaling cascades
Increased expression of inflammatory proteins/medial SMC activation
Immune functions physiologic IFN- Immunoglobulins
Immune-deficiency
Vascular repair and Intimal formation
Hypothesis: B cells are involved in the response toarterial injury.
Methods:•Injure Rag-1 KO mice and compare to WT mice.•“Rescue” Rag-1 KO mice with B cell reconstitutionfrom spleens of WT•Repeat rescue with donor and recipients on westerndiet
Arterial Cuff Injury
Tygon tube
Right carotid artery
harvest spleen from WT mice
squeeze through mesh to isolate cells
add paramagnetic beadscoated with T cell antibody
expose solution to magnetic field andaspirate supe = negative selection of B cells
classify cell populationand/or spin and concentrate
Inject cells into Rag-1 KO mice via tail vein
Cell enrichment procedure
*p<0.05 vs. WT NC; †p<0.05 vs. Rag NC
B cell reconstitution inhibits intimal formationin Rag-1 KO mice fed normal chow
B cell reconstitution inhibits intimal formationin Rag-1 KO mice fed western diet
*p<0.05 vs. WT HC; †p<0.05 vs. Rag HC
WT HC Rag-KO Rag-1 KO Brec
Effect of B cell reconstitution onintimal formation in injured Rag-1 KO mice
Neointimal stain for SM -actin(western diet-fed mice)
WT Rag-1 KO Rag-1 KO Brec
M stain in arteries 21 days after injury(western diet-fed mice)
WT Rag-1 KO Rag-1 KO Brec
IgM in injured arteries of western diet-fed mice
Left contra-lateral (uninjured) Injured right carotid artery
No reconstitution B cell reconstituted
WT
Rag-1 KO
WT
Rag-1 KO
Left contra-lateral (uninjured) Injured right carotid artery
No reconstitution B cell reconstituted
IgG in injured arteries of western diet-fed mice
Relative immunoglobulin levelsin B cell reconstituted mice
Summary of Study
•Neointimal formation after injury is inhibited in Rag-1KO mice reconstituted with B cells regardless of diet.
•Immunoglobulin presence is increased in injuredarteries of WT mice and in B cell reconstituted Rag-1KO mice.