To test the hypothesis that characteristic cytokine responses occur in stim
ulated porcine lymph nodes (LNs), lymph node efferent ducts were surgically
cannulated. Efferent lymph (EL) leukocytes were collected before and after
stimulation of LNs with mitogens [bacterial lipopolysaccharide (LPS) or ph
ytohemagglutinin-P(PHA-P)] and antigens [hen egg white lysozyme (HEWL) or p
urified protein derivative of tuberculin (PPD)]. Cytokine mRNA expression w
as evaluated by quantitative reverse transcription polymerase chain reactio
n (Q-RT-PCR). Interleukin (IL)-1 alpha was predominantly produced after all
stimuli except for HEWL after which tumour necrosis factor (TNF)-alpha mes
sage was dominant. None of the stimuli induced message for IL-2, IL-4 or IL
-8. Other cytokine mRNAs were produced in variable amounts and percentage o
f overall production of each cytokine message was in the following descendi
ng rank: LPS: IL-1 alpha, TNF-alpha, interferon (IFN)-gamma, IL-10, IL-12-p
35, IL-6, IL-12-p40 and TNF-beta; PHA-P: IL-1 alpha, TNF-alpha, IL-10, IFN-
gamma, IL-12-p40 and TNF-beta; HEWL: TNF-alpha, IL-1 alpha, IFN-gamma, IL-1
0, IL-6, IL-12-p40, TNF-beta and IL-12-p35 and PPD: IL-1 alpha, IFN-gamma,
TNF-alpha and IL-10. Time course response of cytokines revealed early (IL-1
alpha, 10, TNF-alpha) and intermediate (IL-12-p40, TNF-beta, IFN-gamma) re
sponses for PHA-P and early (IL-1 alpha, 6, 10, IL-12-p35, IL-12-p40, TNF-a
lpha), intermediate (TNF-beta, IFN-gamma) and late (IL-1 alpha, 6) for LPS.
Cytokine mRNA response induced by HEWL was early (IL-alpha, IFN-gamma), in
termediate (IL-10, IL-12-p40, TNF-beta), late (IL-1 alpha, IL-12-p35) and v
ery late (IL-1 alpha, 6, 10, IL-12-p40, TNF-alpha). In Bacillus Calmette-Gu
erin (BCG) sensitized pigs, stimulation of LNs with PPD induced message for
IL-1 alpha, 10, TNF-alpha and IFN-gamma which peaked at 24 h. Cytokine mRN
As varied by stimulus and differed for antibody and cell-mediated immune re
sponse. (C) 2000 Elsevier Science B.V. All rights reserved.