37586
document
Bacterial ribosomal immunostimulants prime alveolar macrophages in vivo to produce interleukin 1 in vitro . Alveolar macrophages ( AMs ) may play a key role in human respiratory immune defenses , partially by synthesizing and releasing interleukin 1 ( IL = 1 ) . D53 ( Ribomunyl ) , a composite bacterial ribosomal immunostimulant , has been recognized as an efficient prevention of respiratory tract infections . In vitro , D53 enhances the IL-1 production by mouse spleen adherent cells . A thymocyte proliferative response assay was used to evaluate the in vitro IL-1 production by AMs in healthy subjects who received D53 immunostimulant . Twelve nonsmoking healthy subjects took part in a prospective double-blind placebo control study . On day 1 , a first bronchoalveolar lavage ( BAL ) was performed to assess IL-1 production by unstimulated and lipopolysaccharide ( LPS ) stimulated AM . Then , subjects were randomized to receive D53 ( n = 6 ) or its placebo ( n = 6 ) by both oral and subcutaneous injection routes from day 1 to day 15 . On day 15 , a second BAL was done and AM IL-1 production was again tested . IL-1 production on day 15 did not significantly differ from day 1 in both D53-treated and placebo groups either when AMs were unstimulated or were stimulated with concentrations of LPS resulting in maximal IL-1 production . However , in the D53-treated group , but not in the placebo group , IL-1 production induced by low LPS concentration ( 5 mg/L ) was significantly higher ( mean +/- SEM : 1,238 +/- 287 U/10 ( 6 ) AM ) on day 15 in comparison with day 1 ( 577 +/- 113 U/10 ( 6 ) AM ; p less than 0.05 , Wilcoxon W test ) and in comparison with the control group ( day 15 IL-1 production induced by 5 mg/L LPS , 758 +/- 175 U/10 ( 6 ) AM ; p less than 0.05 , Mann-Whitney U test ) . Moreover , in the D53-treated group , the optimal LPS concentration ( ie , LPS concentration that induced maximal IL-1 production ) was significantly lower on day 15 ( mean +/- SD : 11 +/- 7 mg/L ) than on day 1 ( 16 +/- 7 mg/L ; p less than 0.05 Wilcoxon W test ) . We conclude that D53 immunostimulant in vivo primes AM to produce IL-1 following low LPS concentration stimulation . This may partially explain the protective effect of D53 immunostimulant against respiratory tract infection .
37587
Intervention_Pharmacological
Bacterial ribosomal immunostimulants
37588
Intervention_Pharmacological
D53 ( Ribomunyl )
37589
Intervention_Pharmacological
composite bacterial ribosomal immunostimulant
37590
Intervention_Pharmacological
D53
37591
Intervention_Pharmacological
D53 immunostimulant
37592
Intervention_Pharmacological
D53
37593
Intervention_Control
placebo
37594
Intervention_Pharmacological
D53-treated
37595
Intervention_Pharmacological
D53-treated
37596
Intervention_Pharmacological
D53-treated
37597
Intervention_Pharmacological
D53 immunostimulant
37598
Intervention_Pharmacological
D53 immunostimulant
37599
Outcome_Physical
IL-1 production
37600
Outcome_Physical
AM IL-1 production
37601
Outcome_Physical
IL-1 production
37602
Outcome_Physical
IL-1 production
37603
Outcome_Physical
IL-1 production
37604
Outcome_Physical
LPS concentration
37605
Outcome_Physical
IL-1
37606
Outcome_Physical
optimal LPS concentration
37607
Outcome_Physical
IL-1
37608
Outcome_Physical
low LPS concentration
37609
Outcome_Physical
respiratory tract infection
37610
Participant_Condition
healthy
37611
Participant_Sample-size
Twelve
37612
Participant_Condition
nonsmoking healthy
37613
Participant_Condition
respiratory tract infection