From the annals of neurology-response by Prineas and Barnett
Posted: Thu Aug 05, 2004 9:28 am
*See post 5 for summary/explanation of these articles*
First the response to the Prineas findings...
Evidence for Pathogenic Heterogeneity in Multiple
Sclerosis
Claudia F. Lucchinetti, MD,1 Wolfgang Bruck, MD,2
and Hans Lassmann, MD3
Barnett and Prineas recently described extensive oligodendrocyte
apoptosis in the absence of inflammation in a pediatric
multiple sclerosis (MS) case, who died 9 months after disease
onset and 17 hours after presenting with acute pulmonary
edema.1 To what extent perimotem hypoxia may in part
have contributed to the pathological observations in this case
is uncertain. The authors confirm our published reports on
aspects of pattern III MS pathology in a subset of MS patients,
2 however, indicate that the coexistence of remyelinating
lesions and complement activation in other lesions from
this and six other patients suggest that all MS lesions begin
with this type of pathology.
In our experience of 201 immunopathologically classified
MS cases to date,2,3 pattern III MS demonstrates inflammatory
lesions with a preferential loss of myelin associated glycoprotein
(MAG), apoptotic oligodendrocytes, limited remyelination,
and ill-defined inflammatory lesion borders. When
analyzing multiple active lesions in pattern III autopsy cases,
we have not found evidence of complement activation by
using the monoclonal antibody against C9neo antigen. Although
apoptosis is occasionally found in pattern II cases,
this is not associated with MAG loss. In addition, the authors
have not stained their cases for MAG. Furthermore, a
subset of pattern III cases in our series also had Balo-type
concentric lesions, with ongoing remyelination, which is
consistent with the presence of remyelination as described by
Barnett and Prineas.
Detailed clinical follow-up of our early MS cohort (n
99 patients) fails to show any correlation between time of
symptom onset, date of biopsy, and pathological pattern,
thus arguing against all MS lesions beginning with pattern
III pathology.4 In addition, we have observed a striking correlation
between therapeutic response to plasma exchange in
MS patients with evidence for antibody and complement activation
(pattern II pathology, n 10) on biopsy, versus no
response in pattern I (n 3) or pattern III (n 6) cases.5
The sharp border at the active plaque edge with accumulating
macrophages in pattern I and II MS lesions is highly
associated with the presence of ring enhancement on Gd-
MRI, and hypointense T2 rims, whereas these imaging features
are not found in pattern III lesions ( p 0.001; 54
cases examined). Furthermore, on follow-up MRI, we have
not observed ring enhancing lesions in any pattern III case
(n 11).6
Our pathological and clinical observations on a large series
of MS cases continue to support pathogenic heterogeneity in
immune effector mechanisms involved in MS lesion formation,
which persist over a period of time, rather than a single
mechanism dominating the formation of all lesions as suggested
by the authors.
1Department of Neurology, Mayo Clinic, Rochester, MN;
2Department of Neuropathology, University of Gottingen,
Gottingen, Germany; and 3Brain Research Institute, University
of Vienna, Austria
References
1. Barnett MH, Prineas JW. Relapsing and remitting multiple
sclerosis: pathology of the newly forming lesion. Ann Neurol
2004;55:458–468.
2. Lucchinetti CF, Bruck W, Parisi J, et al. Heterogeneity of multiple
sclerosis lesions: implications for the pathogenesis of demyelination.
Ann Neurol 2000;47:707–717.
3. Lucchinetti CF. Merging of minds and matter. Multiple Sclerosis
2003;9(suppl 1):8.
4. Pittock SJ, McClelland FL, Achenbach SJ, et al. The clinical
course of biopsy-proven demyelinating disease and comparison
with a population-based multiple sclerosis prevalence cohort.
Platform presentation at the Eighth Annual ACTRIMS Meeting;
2003; San Francisco, CA.
5. Keegan M, Konig F, Bitsch A, et al. Multiple sclerosis pathological
subtype predicts response to therapeutic plasma exchange.
Neurology 2004;62(suppl 5):S29.A259.
6. Lucchinetti CF, Altintas A, Wegner C, et al. Magnetic resonance
imaging correlates of multiple sclerosis pathologic subtypes. Ann
Neurol 2003;54(suppl 7):S37:67.
DOI: 10.1002/ana.20182
Annals of Neurology
Volume 56, Issue 2, Pages 309
Letter
Reply: Pathological heterogeneity in multiple sclerosis: A reflection of lesion stage?
Michael H. Barnett, MBBS, John W. Prineas, MBBS
Institute of Clinical Neurosciences, Department of Medicine, University of Sydney, Australia
Letter
Pathological Heterogeneity in Multiple Sclerosis: A Reflection of Lesion Stage?
Lucchinetti and colleagues are correct in their assertion that our findings[1] fail to support the concept of a fundamental dichotomy in multiple sclerosis (MS) pathogenesis. The hypothesis is based on a study that found that most patients with MS examined at autopsy fall into two quite distinct groups: one in which remyelinated lesions are absent and tissue breakdown is accompanied by widespread oligodendrocyte apoptosis (type 3 lesions) and a second group in which remyelinated shadow plaques are common and tissue destruction is associated with the activity of macrophages located at the edges of plaques devoid of myelin (type 1 and 2 lesions).[2] Although we describe features not previously known to accompany oligodendrocyte apoptosis in new lesions (ie, complement activation; microglial activation; and the absence of T cells, MRP-14-positive mononuclear cells and macrophages),[1] we agree with Lucchinetti and colleagues that most active lesions appear at autopsy either as sharp-edged lesions or as areas of palely staining myelin sheaths and apoptotic oligodendrocytes. In contrast, however, we observed, in a study of comparable size, both types of lesions in individual patients, as well as evidence of remyelination in all but one of our seven cases with type 3 lesions.[1]
Although our findings strongly suggest that apoptotic lesions are prephagocytic and probably represent an early stage in the formation of most lesions in patients with relapsing and remitting MS, this is not to say that apoptotic lesions evolve directly into active sharp-edged plaques, the early history of which is unknown. New oligodendrocytes and remyelinated nerves are often observed within such plaques, suggesting that they may, in fact, be pre-existing lesions exhibiting fresh activity.[2-4] In support of this notion, apoptotic lesions were found mainly in patients with disease duration of less than 3 months in both our own study and that of Lucchinetti and colleagues,[2] whereas sharp-edged active lesions occurred at all intervals up to 32 years.
Lucchinetti and colleagues are incorrect in asserting that the only evidence of complement activation we provide is based on a figure showing the presence of the serum protein C3d within macrophages. In fact, we describe and illustrate deposition of C3d (Figs 14 and 15) and C9neo (Figs 13 and 12D) on altered myelin and oligodendrocytes.[1] The monoclonal C9neo antibody (clone B7) used was the same as that used in the study by Lucchinetti and colleagues.[2]
Although the correlation between lesion type, magnetic resonance imaging findings, and therapeutic response to plasma exchange reported by Lucchinetti and colleagues is interesting, we feel that it is premature to conclude that the apparent pathological heterogeneity of MS lesions reflects the existence of distinct pathogenic subtypes of the disease.
References
1 Barnett MH, Prineas JW. Relapsing and remitting multiple sclerosis: pathology of the newly forming lesion. Ann Neurol 2004; 55: 458-468. Links
2 Lucchinetti C, Bruck W, Parisi J, et al. Heterogeneity of multiple sclerosis lesions: implications for the pathogenesis of demyelination. Ann Neurol 2000; 47: 707-717. Links
3 Prineas JW, Barnard RO, Revesz T, et al. Multiple sclerosis. Pathology of recurrent lesions. Brain 1993; 116: 681-693. Links
4 Raine CS, Scheinberg L, Waltz JM. Multiple sclerosis. Oligodendrocyte survival and proliferation in an active established lesion. Lab Invest 1981; 45: 534-546. Links
Michael H. Barnett, MBBS, John W. Prineas, MBBS
Institute of Clinical Neurosciences, Department of Medicine, University of Sydney, Australia
First the response to the Prineas findings...
Evidence for Pathogenic Heterogeneity in Multiple
Sclerosis
Claudia F. Lucchinetti, MD,1 Wolfgang Bruck, MD,2
and Hans Lassmann, MD3
Barnett and Prineas recently described extensive oligodendrocyte
apoptosis in the absence of inflammation in a pediatric
multiple sclerosis (MS) case, who died 9 months after disease
onset and 17 hours after presenting with acute pulmonary
edema.1 To what extent perimotem hypoxia may in part
have contributed to the pathological observations in this case
is uncertain. The authors confirm our published reports on
aspects of pattern III MS pathology in a subset of MS patients,
2 however, indicate that the coexistence of remyelinating
lesions and complement activation in other lesions from
this and six other patients suggest that all MS lesions begin
with this type of pathology.
In our experience of 201 immunopathologically classified
MS cases to date,2,3 pattern III MS demonstrates inflammatory
lesions with a preferential loss of myelin associated glycoprotein
(MAG), apoptotic oligodendrocytes, limited remyelination,
and ill-defined inflammatory lesion borders. When
analyzing multiple active lesions in pattern III autopsy cases,
we have not found evidence of complement activation by
using the monoclonal antibody against C9neo antigen. Although
apoptosis is occasionally found in pattern II cases,
this is not associated with MAG loss. In addition, the authors
have not stained their cases for MAG. Furthermore, a
subset of pattern III cases in our series also had Balo-type
concentric lesions, with ongoing remyelination, which is
consistent with the presence of remyelination as described by
Barnett and Prineas.
Detailed clinical follow-up of our early MS cohort (n
99 patients) fails to show any correlation between time of
symptom onset, date of biopsy, and pathological pattern,
thus arguing against all MS lesions beginning with pattern
III pathology.4 In addition, we have observed a striking correlation
between therapeutic response to plasma exchange in
MS patients with evidence for antibody and complement activation
(pattern II pathology, n 10) on biopsy, versus no
response in pattern I (n 3) or pattern III (n 6) cases.5
The sharp border at the active plaque edge with accumulating
macrophages in pattern I and II MS lesions is highly
associated with the presence of ring enhancement on Gd-
MRI, and hypointense T2 rims, whereas these imaging features
are not found in pattern III lesions ( p 0.001; 54
cases examined). Furthermore, on follow-up MRI, we have
not observed ring enhancing lesions in any pattern III case
(n 11).6
Our pathological and clinical observations on a large series
of MS cases continue to support pathogenic heterogeneity in
immune effector mechanisms involved in MS lesion formation,
which persist over a period of time, rather than a single
mechanism dominating the formation of all lesions as suggested
by the authors.
1Department of Neurology, Mayo Clinic, Rochester, MN;
2Department of Neuropathology, University of Gottingen,
Gottingen, Germany; and 3Brain Research Institute, University
of Vienna, Austria
References
1. Barnett MH, Prineas JW. Relapsing and remitting multiple
sclerosis: pathology of the newly forming lesion. Ann Neurol
2004;55:458–468.
2. Lucchinetti CF, Bruck W, Parisi J, et al. Heterogeneity of multiple
sclerosis lesions: implications for the pathogenesis of demyelination.
Ann Neurol 2000;47:707–717.
3. Lucchinetti CF. Merging of minds and matter. Multiple Sclerosis
2003;9(suppl 1):8.
4. Pittock SJ, McClelland FL, Achenbach SJ, et al. The clinical
course of biopsy-proven demyelinating disease and comparison
with a population-based multiple sclerosis prevalence cohort.
Platform presentation at the Eighth Annual ACTRIMS Meeting;
2003; San Francisco, CA.
5. Keegan M, Konig F, Bitsch A, et al. Multiple sclerosis pathological
subtype predicts response to therapeutic plasma exchange.
Neurology 2004;62(suppl 5):S29.A259.
6. Lucchinetti CF, Altintas A, Wegner C, et al. Magnetic resonance
imaging correlates of multiple sclerosis pathologic subtypes. Ann
Neurol 2003;54(suppl 7):S37:67.
DOI: 10.1002/ana.20182
Annals of Neurology
Volume 56, Issue 2, Pages 309
Letter
Reply: Pathological heterogeneity in multiple sclerosis: A reflection of lesion stage?
Michael H. Barnett, MBBS, John W. Prineas, MBBS
Institute of Clinical Neurosciences, Department of Medicine, University of Sydney, Australia
Letter
Pathological Heterogeneity in Multiple Sclerosis: A Reflection of Lesion Stage?
Lucchinetti and colleagues are correct in their assertion that our findings[1] fail to support the concept of a fundamental dichotomy in multiple sclerosis (MS) pathogenesis. The hypothesis is based on a study that found that most patients with MS examined at autopsy fall into two quite distinct groups: one in which remyelinated lesions are absent and tissue breakdown is accompanied by widespread oligodendrocyte apoptosis (type 3 lesions) and a second group in which remyelinated shadow plaques are common and tissue destruction is associated with the activity of macrophages located at the edges of plaques devoid of myelin (type 1 and 2 lesions).[2] Although we describe features not previously known to accompany oligodendrocyte apoptosis in new lesions (ie, complement activation; microglial activation; and the absence of T cells, MRP-14-positive mononuclear cells and macrophages),[1] we agree with Lucchinetti and colleagues that most active lesions appear at autopsy either as sharp-edged lesions or as areas of palely staining myelin sheaths and apoptotic oligodendrocytes. In contrast, however, we observed, in a study of comparable size, both types of lesions in individual patients, as well as evidence of remyelination in all but one of our seven cases with type 3 lesions.[1]
Although our findings strongly suggest that apoptotic lesions are prephagocytic and probably represent an early stage in the formation of most lesions in patients with relapsing and remitting MS, this is not to say that apoptotic lesions evolve directly into active sharp-edged plaques, the early history of which is unknown. New oligodendrocytes and remyelinated nerves are often observed within such plaques, suggesting that they may, in fact, be pre-existing lesions exhibiting fresh activity.[2-4] In support of this notion, apoptotic lesions were found mainly in patients with disease duration of less than 3 months in both our own study and that of Lucchinetti and colleagues,[2] whereas sharp-edged active lesions occurred at all intervals up to 32 years.
Lucchinetti and colleagues are incorrect in asserting that the only evidence of complement activation we provide is based on a figure showing the presence of the serum protein C3d within macrophages. In fact, we describe and illustrate deposition of C3d (Figs 14 and 15) and C9neo (Figs 13 and 12D) on altered myelin and oligodendrocytes.[1] The monoclonal C9neo antibody (clone B7) used was the same as that used in the study by Lucchinetti and colleagues.[2]
Although the correlation between lesion type, magnetic resonance imaging findings, and therapeutic response to plasma exchange reported by Lucchinetti and colleagues is interesting, we feel that it is premature to conclude that the apparent pathological heterogeneity of MS lesions reflects the existence of distinct pathogenic subtypes of the disease.
References
1 Barnett MH, Prineas JW. Relapsing and remitting multiple sclerosis: pathology of the newly forming lesion. Ann Neurol 2004; 55: 458-468. Links
2 Lucchinetti C, Bruck W, Parisi J, et al. Heterogeneity of multiple sclerosis lesions: implications for the pathogenesis of demyelination. Ann Neurol 2000; 47: 707-717. Links
3 Prineas JW, Barnard RO, Revesz T, et al. Multiple sclerosis. Pathology of recurrent lesions. Brain 1993; 116: 681-693. Links
4 Raine CS, Scheinberg L, Waltz JM. Multiple sclerosis. Oligodendrocyte survival and proliferation in an active established lesion. Lab Invest 1981; 45: 534-546. Links
Michael H. Barnett, MBBS, John W. Prineas, MBBS
Institute of Clinical Neurosciences, Department of Medicine, University of Sydney, Australia