TY - JOUR
T1 - Lymph Nodes Draining Infections Investigated by PET and Immunohistochemistry in a Juvenile Porcine Model
AU - Afzelius, Pia
AU - Morsing, Malene Kjelin
AU - Nielsen, Ole Lerberg
AU - Alstrup, Aage Kristian Olsen
AU - Jensen, Svend Borup
AU - Jødal, Lars
PY - 2022/4/27
Y1 - 2022/4/27
N2 - BACKGROUND: [18F]FDG and [11C]methionine accumulate in lymph nodes draining S. aureus -infected foci. The lymph nodes were characterized by weight, [11C]methionine- and [18F]FDG-positron emissions tomography (PET)/computed tomography (CT), and immunohistochemical (IHC)-staining.METHODS: 20 pigs inoculated with S. aureus into the right femoral artery were PET/CT-scanned with [18F]FDG, and nine of the pigs were additionally scanned with [11C]methionine. Mammary, medial iliac, and popliteal lymph nodes from the left and right hind limbs were weighed. IHC-staining for calculations of area fractions of Ki-67, L1, and IL-8 positive cells was done in mammary and popliteal lymph nodes from the nine pigs.RESULTS: The pigs developed one to six osteomyelitis foci. Some pigs developed contiguous infections of peri-osseous tissue and inoculation-site abscesses. Weights of mammary and medial iliac lymph nodes and their [18F]FDG maximum Standardized Uptake Values (SUVFDGmax) showed a significant increase in the inoculated limb compared to the left limb. Popliteal lymph node weight and their FDG uptake did not differ significantly between hind limbs. Area fractions of Ki-67 and IL-8 in the right mammary lymph nodes and SUVMetmax in the right popliteal lymph nodes were significantly increased compared with the left side.CONCLUSION: The PET-tracers [18F]FDG and [11C]methionine, and the IHC- markers Ki-67 and IL-8, but not L1, showed increased values in lymph nodes draining soft tissues infected with S. aureus. The increase in [11C]methionine may indicate a more acute lymph node response, whereas an increase in [18F]FDG may indicate a more chronic response.
AB - BACKGROUND: [18F]FDG and [11C]methionine accumulate in lymph nodes draining S. aureus -infected foci. The lymph nodes were characterized by weight, [11C]methionine- and [18F]FDG-positron emissions tomography (PET)/computed tomography (CT), and immunohistochemical (IHC)-staining.METHODS: 20 pigs inoculated with S. aureus into the right femoral artery were PET/CT-scanned with [18F]FDG, and nine of the pigs were additionally scanned with [11C]methionine. Mammary, medial iliac, and popliteal lymph nodes from the left and right hind limbs were weighed. IHC-staining for calculations of area fractions of Ki-67, L1, and IL-8 positive cells was done in mammary and popliteal lymph nodes from the nine pigs.RESULTS: The pigs developed one to six osteomyelitis foci. Some pigs developed contiguous infections of peri-osseous tissue and inoculation-site abscesses. Weights of mammary and medial iliac lymph nodes and their [18F]FDG maximum Standardized Uptake Values (SUVFDGmax) showed a significant increase in the inoculated limb compared to the left limb. Popliteal lymph node weight and their FDG uptake did not differ significantly between hind limbs. Area fractions of Ki-67 and IL-8 in the right mammary lymph nodes and SUVMetmax in the right popliteal lymph nodes were significantly increased compared with the left side.CONCLUSION: The PET-tracers [18F]FDG and [11C]methionine, and the IHC- markers Ki-67 and IL-8, but not L1, showed increased values in lymph nodes draining soft tissues infected with S. aureus. The increase in [11C]methionine may indicate a more acute lymph node response, whereas an increase in [18F]FDG may indicate a more chronic response.
KW - Animals
KW - Fluorodeoxyglucose F18
KW - Immunohistochemistry
KW - Interleukin-8
KW - Ki-67 Antigen
KW - Lymph Nodes/diagnostic imaging
KW - Methionine
KW - Positron Emission Tomography Computed Tomography
KW - Positron-Emission Tomography
KW - Radiopharmaceuticals
KW - Staphylococcus aureus
KW - Swine
UR - http://www.scopus.com/inward/record.url?scp=85129831693&partnerID=8YFLogxK
U2 - 10.3390/molecules27092792
DO - 10.3390/molecules27092792
M3 - Journal article
C2 - 35566137
SN - 1420-3049
VL - 27
JO - Molecules
JF - Molecules
IS - 9
M1 - 2792
ER -