Alessandro Fiocchi pdf

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Immunomodulatori:

come agiscono?

Alessandro Fiocchi

Caserta, 14 settembre 2012

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Educational objectives

At the end of this lecture, participants will be able to:

Understand the rationale behind the use of BRMs in prevention and treatment of RRI

Identify the new avenues of research in the field Identify the new avenues of research in the field

Assess the impact of a BRMs in healthy, socialised children

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Conflict of interest

Speakers’ Bureau: none

Advisory boards: ALK-Abellò, Pierre Fabre, Stallergènes Italy

Currently sponsored research: MSD, GSK, Pierre Fabre, Paul Ehrlich Institute, Roxall.

This lecture is sponsored by Valeas

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Se il bambino si ammala troppo spesso... infezioni catarrali ricorrenti A parte i discorsi su ambiente sano ed alimentazione sana, si cercherà di evitare i contagi diretti e di abituare il bambino a frequenti lavaggi delle mani.

Comunque, non servono assolutamente i molti vaccini per bocca o immunomodulatori, che impropriamente sono considerati ricostituenti. I benefici, rispetto ai costi, sono molto limitati; resta sempre aperto il problema della "medicalizzazione" di una situazione non grave e quindi accettabile da parte del bambino e dei suoi genitori. Meglio accettare una infezione benigna in parte del bambino e dei suoi genitori. Meglio accettare una infezione benigna in più piuttosto che sottoporre il bambino a cure costose e di limitata importanza.

[….] non è nemmeno scientifico. Infatti recenti ricerche affermano che, se eliminiamo queste "piccole" malattie, possiamo registrare un aumento di allergie (asma, eczema, riniti allergiche,…), per deviazione nella maturazione

dei linfociti, nostre cellule di difesa. Le reazioni del nostro organismo a queste malattie infettive sono utili, perché maturano il nostro sistema

immunitario di difesa.

http://www.archivio.vivoscuola.it/genitori/famiglia/infezioni.asp

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.

1. Cosa sappiamo oggi sulle infezioni respiratorie recidivanti?

2. I bambini a rischio 2. I bambini a rischio 3.

3. I BRM I BRM possonopossono agireagire sull’immunitàsull’immunità innatainnata 4. I BRM

4. I BRM possonopossono agireagire sull’immunitàsull’immunità adattivaadattiva 5. I BRM

5. I BRM possonopossono agireagire sull’immunitàsull’immunità naturalenaturale 6.

6. ConcludoConcludo 7. Post

7. Post--concludoconcludo

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Che carico rappresentano per la società le infezioni respiratorie acute?

Sono responsabili di: 20% di tutte le visite mediche 30% dei giorni persi dal lavoro 75% delle prescrizioni di antibiotici Quanti episodi all’anno?

0 2 4 6 8

0-1 1-4 5-9 10-19

età

Calcolato su una popolazione rurale

che non frequenta asilo

Del Rio- Navarro N. Immunostimulants for preventing respiratory tract infection in children. Cochrane Database Syst Rev. 2011;(4):CD004974.

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6

4

Number episoeds/person/year

# respiratory infections/year by age class

2

Number episoeds/person/year

età [anni]

<1 1-2 3-4 5-9 10-14 15-19 20-24 25-29 30-39 40-49 50-59 ≥60

Heikkinen T, Järvinen A. The common cold. Lancet. 2003; 361:51-9

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World-wide distribution of child deaths from ARI

Williams BG. Estimates of world-wide distribution of child deaths from acute respiratory infections. Lancet Infect Dis 2002;2:25-32

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.

2. I bambini a rischio 3

3.. I BRM I BRM possonopossono agireagire sull’immunitàsull’immunità innatainnata 4. I BRM

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Some children as a group show high morbidity

• 41 school-age children with RRTIs [antibiotics] as preschoolers (a)

vs.

• 29 children (same age and socio-economic background) whithout RRTIs as preschoolers (b)

Two-year follow-up:

• RTI episodes a>b (p < 0.01)

• RTI duration a>b (p < 0.01)

Soderstrom M Respiratory tract infections in children with recurrent episodes as preschoolers. Acta Paediatr Scand. 1991;80:688-95

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Certain children constitute a group with high morbidity

Annual incidence of bacterial RTI:

Age Group a Group b P

2 yrs 6.2 1.4 < 0.001

7 yrs 3.1 1.2 < 0.01

Children with high morbidity are susceptible to RTIs and other illnesses over a long period of years

7 yrs 3.1 1.2 < 0.01

8 yrs 2.4 0.8 < 0.05

Soderstrom M Respiratory tract infections in children with recurrent episodes as preschoolers. Acta Paediatr Scand. 1991;80:688-95

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Recurrent respiratory infections can be linked to minor immune defects

IgG2 subclass deficiency pneumonia, sinusitis, invasive pneumococcal disease

IgA deficiency pneumonia, otitis, diarrhoea

G2m(n) allotype of IgG2 susceptibility to encapsulated bacteria Fc receptor IIa: H131 high affinity, FcRIIa-R131 low affinity for IgG2

Heterozygotic C2 deficiency in 1%–1.5% of the general population Homozygous deficiency of C4A or C4B in 3% of the population Mannose-binding lectin (MBL2) activates the complement system

Bossuyt X. Coexistence of (partial) immune defects and risk of recurrent respiratory infections. Clin Chem. 2007;53:124-30

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.

2. I bambini a rischio

3. I BRM possono agire sull’immunità innata 4. I BRM

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TT T TT

T

Uninvolved

Th2Th2 Th0 Th2

Th0

Th0 ^IL-10^IL-10

IL-13 IL-4 IL-5 IL-13 IL-4 IL-5

Y

Th0Th0

Th0 ^IL-12^IL-12 Th1Th1Th1

IFN- IL-4IL-4 remodelingremodeling

MCMC

Y

TT T

IDECIDEC

IFN-γγγγ IL-11 IFN-γγγγ IL-11

Y

T Y T

T TTT TTT Y Y Y Y TT

T Y

Y Y remodelingremodeling

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McAleer JP. Educating CD4 T cells with vaccine adjuvants: lessons from LPS.

Trends Immunol. 2010;31:429-35

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Human Toll - like receptors and their ligands.

Peptidoglycan (G+) Lipoprotein

GPI (Trypanosoma cruzi) Zymosan (Yeast)

Mycobacterial lipopeptides

Measles and CMV proteins dsRNA

LPS (G-) LPS (G+)

Lipoteichoic acids (G+)

RSV F protein ssRNA

Unmethylated CpG DNA

Uropatho genic bacteria Flagellin

Courtesy of Lorenzo Moretta

TLR 6 TLR 2 TLR 1 TLR 4

CD14

TLR 3 TLR 5 TLR 9

MD-2

TLR 7 TLR 8 TLR 11

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Different cell types of the innate immune system can modulate NK-cell responses upon interaction with different microbial

products

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Ribomunyl is a potent antiviral Toll-like receptor 7/8 agonist.

Ribomunyl has been proposed to activate innate immunity, but the contribution of its RNA content as well as its antiviral

potential has not been studied.

Peripheral blood mononuclear cells (PBMC) from healthy donors & from adenoids incubated with Ribomunyl

- itself

- + poly-l-arginine or protamine

⇒ induction of cytokines quantified by ELISA.

Herberhold S. Delivery with polycations extends the immunostimulant Ribomunyl into a potent antiviral Toll-like receptor 7/8 agonist. Antivir Ther. 2011;16:751-8

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Ribomunyl is a potent antiviral Toll-like receptor 7/8 agonist.

Ribomunyl + either poly-l-arginine or protamine

⇑ interferon-α (P<0.01) in PBMC

⇑ IL-12 (P<0.01) in PBMC

= TNF-α and IL-6

The RNA in Ribomunyl acts as an agonist of TLR7 and TLR8.

Herberhold S. Delivery with polycations extends the immunostimulant Ribomunyl into a potent antiviral Toll-like receptor 7/8 agonist. Antivir Ther. 2011;16:751-8

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.

3. I BRM possono agire sull’immunità innata 4. I BRM possono agire sull’immunità adattiva 5. I BRM

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Absence of CD30 leads to reduced airway inflammation in OVA-immunized mice.

Polte T. Direct evidence for a critical role of CD30 in the development of allergic asthma. J Allergy Clin Immunol. 2006;118:942-8

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Absence of CD30 leads to reduced airway inflammation and mucus production in OVA-

immunized mice.

Polte T. Direct evidence for a critical role of CD30 in the development of allergic asthma. J Allergy Clin Immunol. 2006;118:942-8

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OH

+

N

S

=

S

N

Pidotimod

O

N H

C O

OH H N

COOH

N H

C

O COOH N

L-Piroglutammic acid

L-Tiazolidin-4-Carbossilic acid

Pidotimod

A synthetic dipeptide with with biological & immunological activity on both the adaptive and the innate immune

responses

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Pidotimod decreases the in vitro expression of CD30

Peripheral blood mononuclear cells from 13 atopic asthmatic vs. 9 normal children

Mithogenesis in vitro

Pidotimod

⇓

CD30 (associated with Th-2 cells)

Pidotimod affects the Th-1/Th-2 balance in atopic asthma.

Gourgiotis D. Immune modulator pidotimod decreases the in vitro expression of CD30 in peripheral blood mononuclear cells of atopic asthmatic and normal children. J Asthma. 2004;41:285-7

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S

Macrophage

NK-cells

Biological activities of Pidotimod in experimental studies

N H

C

O COOH N

Pidotimod Pidotimod Macrophage

T-cells Neutrophils

I.G.G.

Courtesy of Giovanni Rossi MD

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.

3. I BRM possono agire sull’immunità innata 4. I BRM possono agire sull’immunità adattiva 5. I BRM possono agire sull’immunità naturale

6.

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Phagocytosis and intracellular killing of bacteria by human blood neutrophils and alveolar

macrophages

Neutrophil

Oddera et al. Drugs Exp Clin Res 1993; 19: 27-35.

I.G.G.

Alveolar macrophage

Bacteria

+ Dapi = alive

PI = dead

Pidotimod

Fluorescence microscopy

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Activity of Pidotimod on phagocytosis and intracellular killing of S. aureus by human

polymorphonuclear leukocytes

30

24

18

% bacteria/cell

Phagocytosed Killed

*

^p<0.05

*

18

12

6

0

% bacteria/cell

*

Controls Pidotimod Pidotimod Pidotimod 1 mg/ml 10 mg/ml 100 mg/ml

* *

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Activity of Pidotimod on H2O2 production by human

polymorphonuclear leukocytes

H2O2 production

* =p<0,05

50

40

30

TPA Medium

*

H2O2 production

* 30

20

10

0

Controls Pidotimod Pidotimod Pidotimod 1 mg/ml 10 mg/ml 100 mg/ml

*

I.G.G.

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Pidotimod synergized with cefotaxime in protecting mice against bacterial infections

Pidotimod

+ + ^Cefotaxime ^Controls

Pidotimod Cefotaxime

Pidotimod + Cefotaxime

100

80

% of survival

Coppi et al. Arzneim Forsch Drug Res 1994; 44: 1417-21. I.G.G.I.G.G.I.G.G.I.G.G.

60

40

20

0

% of survival

E. coli 60

0 10

90

P. vulgaris 40 40 0

100 90

P. mirabilis 50

0 20

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Partial protective effect on experimental Coxsackie virus-induced infections in mice

100

80

60

Pidotimod 25-100 mg/kg

+

Dianzani et al. Arzneim Forsch Drug Res 1994; 44: 1431-33

60

40

20

0

% survival

0 1 2 3 4 5 6 7 8 9 10

Controls

Pidotimod 25 mg/kg Pidotimod 50 mg/kg Pidotimod 100 mg/kg

Days

I.G.G.

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Protective effect on experimental Influenza virus-induced infections in mice

Pidotimod 25-100 mg/kg

+

100

80

60

% survival

Dianzani et al. Arzneim Forsch Drug Res 1994; 44: 1431-33

60

40

20

0

% survival

0 1 2 3 4 5 6 7 8 9 10

Controls

Pidotimod 25 mg/kg Pidotimod 50 mg/kg Pidotimod 100 mg/kg

Days

I.G.G.

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Clinical evaluation and changes in ciliary clearance after Pidotimod (PID) in Greek children with

recurrent repiratory tract infections

• Clinical evaluation

• N° of RTI A. 32 children

(active group) PID 400 mg bid x 15 days + PID 400 mg od x 20

• N° of RTI (at 9 months)

Aivazis V. Minerva Pediatr 2002, 54: 315-319 Children (2.5-12 yrs) with

>3 URTI or LRTI in the last 6 months

mg od x 20 days

B. 18 children (control group)

I.G.G.

• Changes in ciliary clearance

(at 6 months)

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Number of respiratory tract infections in children treated with Pidotimod and controls

100

80

60

% of patients

Children with > 3 RTI

p < 0.001

***

Aivazis V. Minerva Pediatr 2002, 54: 315-319 I.G.G.I.G.G.I.G.G.I.G.G.

40

20

0

% of patients

Pidotimod Controls (4/32) (10/18)

12.5

66.7

**

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Respiratory epithelium ciliary clearance in children treated with Pidotimod and controls

Pidotimod Controls

75

60

45

Mean time (MT) + SD

A. Respiratory epithelium clearance

p<0.001

Aivazis V. Minerva Pediatr 2002, 54: 315-319

30

15

0

Before 1 month 6 month treatment after after

Mean time (MT) + SD

37.2 33.2

19.2

36.2 32.2 31.2

Before 1 month 6 month treatment after after

I.G.G.

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Efficacy of Pidotimod administration in the acute phase of URTI:

a) Pyrexia; b) Antibiotic therapy; c) Absence from school

15

12

9

Days (numbers)

Pidotimod Placebo

**

9

6

3

0

Days (numbers)

4.5

6.1 8.0

10.5 11.1

13.3

p < 0.01

**

Pyrexia Antibiotic therapy Absence from school

Caramia G. Arzneim-Forsch/Drug Res.1994; 44: 1480-82 I.G.G.I.G.G.I.G.G.I.G.G.

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.

6. Concludo 7. Post

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Conclusions

• Clinical trials show the efficacy of BRMs in reducing the recurrency of upper and lower RTI in children

• Both bacterial lysates and Pidotimod, administered to children with RRI, may lead to a better clinical outcome

• Further studies on BRMs are needed to:

- Better characterize the mechanisms of action

- Confirm the clinical efficacy in multicenter international trials

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.

6. Concludo 7. Post-concludo

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Post-scriptum

Questa notte ho riflettuto - e ho buttato giù di getto quattro righe in stile arguto. Solo un piccolo sonetto

in onore del baffuto - Presidente quasi-eletto.

E rompendo irritualmente - il silenzio elettorale E rompendo irritualmente - il silenzio elettorale mi riporto con la mente - al programma magistrale che da vicepresidente - nel mandato quadriennale

ho collaborato a fare. Dal lavaggio delle mani

alle spiagge sopra il mare, dalle orecchie ai denti sani ai vaccini da impostare - fino a temi anche più strani:

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Post-scriptum

il bambino capriccioso, i pidocchi sulla testa, il fratello litigioso e l’obesità che infesta,

il tabacco che è dannoso, …. non so più che cosa resta.

Vorrei avere la sua verve nel portar le iniziative sempre oltre le riserve, le prudenze più retrive.

se di voti farà il pieno sarà un record senza meno:

e così il terzo mandato e la sua delega in bianco con l’ardor certificato di Caudillo non mai stanco sarà accolto dal boato: W il nostro Pino Franco!

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