Can we restore the response to erythropoietin resistance ? Iain C Macdougall BSc, MD, FRCP...
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Transcript of Can we restore the response to erythropoietin resistance ? Iain C Macdougall BSc, MD, FRCP...
Can we restore the response to erythropoietin resistance ?
Iain C Macdougall BSc, MD, FRCP
Consultant Nephrologist and Honorary Senior Lecturer
Renal Unit, King’s College Hospital, London, UK
0 2 4 6 8 10 12
6
8
10
12
14
90-95% of patients respond well to ESAs
Time on therapy (months)
Hb
(g
/dl)
0 2 4 6 8 10 12
6
8
10
12
14
Time on therapy (months)
Hb
(g
/dl)
Type 1 poor response to ESAs
0 2 4 6 8 10 12
6
8
10
12
14
Type 2 poor response to ESAsH
b (
g/d
l)
Time on therapy (months)
Poor response to ESAs - causes
Major Minor
Iron deficiency Blood loss
Infection / inflammation Hyperparathyroidism
Underdialysis Aluminium toxicity
B12 / folate deficiency
Haemolysis
Marrow disorders, e.g. MDS
Haemoglobinopathies
ACE inhibitors
Carnitine deficiency
Anti-EPO antibodies
Dialysis adequacy
Infection, Inflammation
Iron supplementation
Blood losses
AT
Dialysis adequacy
Infection, Inflammation
Iron supplementation
Blood loss
AT
Factors influencing response to ESAs
AT = Adjuvant therapy
Epoetin dose and Hb levels in patients with chronic infection/inflammation (ESAM)
0
25
50
75
100
125
150
175
1 2 3 4 5 6 0
2
4
6
8
10
12
14
1 2 3 4 5 6
Epoetin doseEpoetin dose HaemoglobinHaemoglobin
Mea
n (
IU/k
g/w
eek)
Mea
n (
IU/k
g/w
eek)
Mea
n (
g/d
l)M
ean
(g
/dl)
CRPCRP50 mg/l on 3 or more months (n=201)50 mg/l on 3 or more months (n=201)
CRP<50 mg/l on 4 or more months (n=3,014)CRP<50 mg/l on 4 or more months (n=3,014)
MonthMonth MonthMonth
Hörl W et al., NDT 2000;15(Suppl 4): 45–45.
Inflammatory response and EPO doseInflammatory response and EPO doseSitter et al NDT 15:1207,2000.Sitter et al NDT 15:1207,2000.
30–50% of CKD patients have serological evidence ofan activated inflammatory response (CRP > 8–10 mg/l).
Influence of CRP concentration on EPO dose
180
160
140
120
100
80
60
40
20
0
EP
O d
os
e [
IU/k
g/w
eek]
Group I:CRP > 10 mg/l
Group II:CRP < 10 mg/l
P<0.01
138.7
92
Stenvinkel P, NDT 2002;17 Suppl 5:32–37.Nitta K, Acta Haematol 2002;108;168–170.
34% difference in EPO dose
What do you do about the patient who is responding poorly to ESAs in the absence of any obvious cause ?
The explanation ?
Uraemia Chronic inflammation (c.f. anaemia of chronic disease,
e.g. RA, malignancy)
IL-1
IL-6
TNF-
IFN-
Suppression of erythropoiesis
Factors affecting erythropoiesis
Erythroidprogenitor
cell
EPO +ve
BFU-E
CFU-E
Erythroblast
Red blood cells
Bone Marrow
Pro-inflammatory cytokines
-ve
Where do cytokines come from ?
T-cell
Th0
Th1IFN-
Th2IL-4
IL-10IL-2
CD8
CD8+T-cell
IL-2
TNF-
CD4
MonocyteIL-6
IL-12
TNF-
Aim
To examine whether HD patients responding poorly to EPO have altered T cell and monocyte activation states compared with:
– Patients responding well to EPO– Normal controls
3 groups of subjects:
1 - HD patients not responding to EPO (Hb < 10g/dl, EPO dose > 250 IU/kg/wk)
2 - HD patients responding well to EPO (Hb > 11g/dl, EPO dose < 200 IU/kg/wk)
3 - Normal healthy controls
Demographic and haematological characteristics of subjects (mean±SD)
Normalcontrols(n=17)
Goodresponders
(n=17)
Poorresponders
(n=15)
Age (yrs) 40±15 58±18# 56±18†
Hb (g/dl) 14.1±1.1 11.8±1.3## 8.9±1.7††**
CRP (mg/l) 3.8±1.1 8.7±8.0# 18.6±20.7††*
EPO dose(U/kg/week)
N/A 71±30 296±147**
EPOdose/Hbratio
N/A 6.3±2.6 33.4±17.8**
Hb levels and EPO dose requirements
60050040030020010004
6
8
10
12
14
16
18
Hb
(g
/dl)
Hb
(g
/dl)
Good responders
ControlsControls
Poor respondersPoor responders
EPO dose (IU/kg/wk)EPO dose (IU/kg/wk)
Intracellular cytokine methodology
Whole blood
Peripheral blood mononuclear cells
Culture for 48h @ 37°C, 5% CO2
3 colour flow cytometric analysis
PMA/ionomycinBrefeldin A
Surface stain cells with fluorescent mabs to CD3 & CD8
Permeabilize cells and stain for intracellular cytokines
CD4+ T-cell expression of IFN stimulated by PMA/ionomycin
0
10
20
30
CD
4+ T
cel
ls e
xpre
ssin
g IF
N
(%)
0
10
20
30
Normalcontrols
Goodresponders
Poorresponders
Normalcontrols
Goodresponders
Poorresponders
P <0.005
P <0.005ns
CD8+ T-cell expression of IFN stimulated by PMA/ionomycin
0
25
50
75
100
0
25
50
75
100
CD
8+ T
cel
ls e
xpre
ssin
g IF
N
(%)
Normalcontrols
Goodresponders
Poorresponders
Normalcontrols
Goodresponders
Poorresponders
P <0.005
nsns
CD4+ T-cell expression of TNF stimulated by PMA/ionomycin
0
20
40
60
80
CD
4+ T
cel
ls e
xpre
ssin
g T
NF
(%
)
0
20
40
60
80
Normalcontrols
Goodresponders
Poorresponders
Normalcontrols
Goodresponders
Poorresponders
P <0.05
P <0.01ns
CD8+ T-cell expression of TNF stimulated by PMA/ionomycin
0
20
40
60
80
CD
8+ T
cel
ls e
xpre
ssin
g T
NF
(%
)
0
20
40
60
80
P <0.001
nsns
Normalcontrols
Goodresponders
Poorresponders
Normalcontrols
Goodresponders
Poorresponders
CD4+ T cell expression of IL-10 stimulated by PMA/ionomycin
Normalcontrols
Goodresponders
Poorresponders
Normalcontrols
Goodresponders
Poorresponders
CD
4+ T
cel
ls e
xpre
ssin
g IL
-10
(%
)
0
1
2
3
0.0
0.5
1.0
1.5
2.0
2.5
3.0
P <0.05
nsns
CD8+ T cell expression of IL-10 stimulated by PMA/ionomycin
0
1
2
3
4
0
1
2
3
4
Normalcontrols
Goodresponders
Poorresponders
Normalcontrols
Goodresponders
Poorresponders
CD
8+ T
cel
ls e
xpre
ssin
g IL
-10
(%
) P <0.001
P <0.05P <0.02
Summary of intracellular cytokine staining study
TNF IFN IL-10
CD4 increased increased trend forincrease
CD8 trend forincrease
trend forincrease
increased
0 5 10 15 20 25
50
Pe
rce
nt
surv
ival
Time (months)
Poor responders
Good responders100
0
*
* P < 0.05 poor responders versus good responders
Kaplan Meyer survival curve for poor responders versus good responders over 24 months
Cooper et al, Nephrol Dial Transplant (2003)
Conclusions
Poor response to EPO is associated with:
– Increased capacity to generate IFN and TNF from CD4+ and CD8+ T cells
In the absence of any other cause, poor response to ESAs may result from enhanced T cell activation
Cytokine-mediated inhibition of erythropoiesis
Proposed model of inhibition in poor responders to EPO therapy
Erythroidprogenitor
cellproliferation
Uraemia (± other inflammatory conditions)
Immune activation
CD8+T cell
CD4+T cell
–ve
–ve
–ve
–ve
TNF
IL-10
IL-13
IFN
+veEPOanti-apoptotic
pro-apoptotic
Cooper et al JASN 2003
Blocking cytokine production
Increase dialysis prescription
Drugs
– Pentoxifylline
– Thalidomide
– Anti-cytokine antibodies
– Anti-lymphocyte therapy
Pentoxifylline
Phosphodiesterase inhibitor
Useful in peripheral vascular disease:
– Anti-platelet effect
– Effect on erythrocyte deformability
Anti-TNF effect
Anti-IFN effect
Anti-IL-10
Anti-oxidant effect
Anti-apoptotic effect
Pentoxifylline trials
IBD– Improved disease activity index– Correction of inflammatory markers
(Blam et al, 2001)
Dilated cardiomyopathy– Improved exercise tolerance– Improved ejection fraction
(Skudicky et al, 2001)
Septic shock– Improved GFR– Correction of coagulopathy
(Jaimes et al, 2001)
Membranous nephropathy
– Reduction of proteinuria (Duclox et al, 2001)
Effect of Pentoxifylline treatment on TNF production in a patient with poor response to erythropoietin therapy
CD
3
TNFTNF
60% 9%
Before treatment After treatment(6 weeks)
Effect of Pentoxifylline treatment on IFN production in a patient with poor response to erythropoietin therapy
CD
3
IFNIFN
24% 6%
Before treatment After treatment(6 weeks)
Pentoxifylline studyProtocol
At recruitment• blood sample taken for T cell cytokines• patients given 400 mg pentoxifylline od
Hb monitored monthly
6-8 weeks blood sample taken for T cell cytokines
Pentoxifylline study
16 patients were recruited
12 patients completed the study
2 patients were non-compliant
1 patient developed nausea
1 patient developed confusion unrelated to therapy
Before treatment
After treatment(6–8 weeks)
TNF (%)
0
25
75p=0.0007
Effect of pentoxifylline treatment on ex vivo cytokine production by CD3+ T cells
50
Before treatment
After treatment(6–8 weeks)
IFN (%)
p=0.0002
0
10
20
30
40
50
Effect of pentoxifylline treatment on Hb level (n=12)
Pentoxifylline therapy (months)
Hb(g/dl)
pentoxifylline
-6 -5 -4 -3 -2 -1 0 1 2 3 40
2
4
6
8
10
12
14
P = 0.0001
Conclusions
• Pro-inflammatory cytokines in renal failure may be an important cause of a poor response to ESAs
• Pentoxifylline may be a useful adjuvant therapy in patients who respond poorly to ESAs
What can we do to restore the response to erythropoietin resistance ?
• Ensure compliance if self-administering
• Ensure adequate iron status ? trial of IV iron
• Exclude / treat other deficiencies e.g. B12/folate/thyroxine
• ? parathyroidectomy if severe hyperparathyroidism
• Treat any infection/inflammatory cause aggressively ? transplant nephrectomy
• Increase dialysis prescription
• ? consider pentoxifylline if “inflammation” present and other causes excluded
• Pro-inflammatory cytokines in renal failure may be an important cause of resistance to ESAs