EXPEDITED ARTICLE

Brief Reports

Transplanted DopaminergicNeurons Develop PD PathologicChanges: A Second Case Report

Jeffrey H. Kordower, PhD,1* Yaping Chu, MD,1

Robert A. Hauser, MD,2 C.Warren Olanow, MD,3

and Thomas B. Freeman, MD4

1Department of Neurological Sciences, Rush UniversityMedical Center, Chicago, Illinois, USA; 2Department of

Neurology, University of South Florida, Tampa,Florida, USA; 3Department of Neurology, Mt. Sinai Schoolof Medicine, New York, New York, USA; 4Department of

Neurosurgery, University of South Florida, Tampa,Florida, USA

Abstract: This report describes pathological changeswithin the grafted neurons of another patient with Par-kinson’s disease (PD) who died 14 years posttransplanta-tion. Although numerous healthy appearing grafted neu-rons were present at this long-term time point, somedisplayed Lewy bodies as evidenced by alpha-synuclein,ubiquitin, and thioflavin-S staining. Additionally, therewas a general loss of dopamine transporter-immunoreac-tivity in grafted neurons. Some grafted cell displayed aloss of tyrosine hydroxylase. These data support theemerging concept that PD-like pathology is seen in younggrafted neurons when they survive long term. � 2008Movement Disorder Society

Key words: transplantation; substantial nigra; Lewy body

A series of 3 recently reported papers described

pathologic findings in patients with Parkinson’s disease

(PD) who had undergone fetal nigral transplantation 10

to 16 years prior.1–3 Two studies demonstrated that

substantial numbers of implanted dopaminergic neu-

rons contained inclusions that stained for ubiquitin and

alpha-synuclein and were identical to Lewy bodies.

The third reported healthy appearing grafted cells with

no inclusions,3 however subsequent analyses revealed

rare ubiquinated Lewy bodies within the graft of one

of their cases (O. Isacson, presented at the Michael J.

Fox Workshop, 2008). We now report the results of a

postmortem study on another individual with PD who

died 14 years after fetal nigral transplantation.

CASE REPORT

MK was a 38-year-old man at the time of diagnosis

followed by a 25-year progression of PD at which time

informed consent was obtained for bilateral fetal trans-

plantation.4 The patient initially had a good response

to levodopa therapy, but benefits were compromised by

severe motor complications that could not be satisfac-

torily controlled with manipulation of antiparkinsonian

medications. In June and July of 1994, the patient

underwent bilateral fetal nigral transplant procedures

using solid grafts derived from four donors aged 6.5 to

9 weeks post-conception per side. The patient enjoyed

substantial improvement for 12 years, but deteriorated

thereafter, and died 2 years later on May 18, 2008. Au-

topsy was obtained with a 3-hour-postmortem interval.

POSTMORTEM EXAMINATION

The brain was processed as previously described.5

Gross examination was unremarkable except for typical

PD pathology including depigmentation of the substan-

tia nigra pars compacta (SNc) and locus coeruleous.

On microscopic examination, there was profound loss

of tyrosine hydroxylase (TH) and melanized neurons in

the SNc coupled with characteristic intracytoplasmic

Lewy bodies which stained positively for ubiquitin,

alpha-synuclein, and thioflavin-S.

Within the left striatum there was robust survival of

implanted neurons in all graft deposits. In the right

striatum there were surviving graft deposits, but, there

were considerably fewer melanin or TH-positive cells.

These cells displayed classic morphology of midbrain

dopaminergic neurons with age-appropriate melanin

content. Grafts gave rise to large numbers of axons

that extensively innervated the postcommissural puta-

men in an organotypic manner as we have previously

Potential conflict of interest: None reported.

*Correspondence to: Dr. Jeffrey H. Kordower, Department of Neu-rological Sciences, Rush University Medical Center, 1735 West Har-rison Street, Chicago Illinois 60612, USA.E-mail: jkordowe@rush.edu

Received 12 September 2008; Revised 1 October 2008; Accepted3 October 2008

Published online 12 November 2008 in Wiley InterScience

(www.interscience.wiley.com). DOI: 10.1002/mds.22369

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Movement DisordersVol. 23, No. 16, 2008, pp. 2303–2306� 2008 Movement Disorder Society

FIG. 1. Low- (A) and (B) high-power photomicrographs illustrating the robust immunoreactivity was seen within grafted neurons for VMAT2.In contrast (C,D) spare immunoreactivity was seen within grafted neurons stained for DAT. For the most part, grafted neurons displayed robustTH (E,F). (G) However, some melanin-containing grafted neurons failed to express TH (arrows). Scale bar in G represents the following magnifi-cations: 160 lm for A and C; 320 lm for E; 25 lm for B, D, F, and G.

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Movement Disorders, Vol. 23, No. 16, 2008

described. Virtually all grafted neurons stained posi-

tively for vesicular monoamine transporter 2 (VMAT2;

Fig. 1A,B). However, there was very little staining for

dopamine transporter (DAT; Fig. 1C,D) in all graft

deposits with some displaying virtually none. Although

most implanted cells stained positively for TH (Fig.

1E,F), many did not (Fig. 1G), in contrast to our previ-

ous findings. Within a minority of grafted melanin con-

taining neurons there were large intracellular inclusions

that stained for ubiquitin, alpha-synuclein, and Thiofla-

vin-S (Fig. 2). These were identical in staining pattern

and morphology to Lewy bodies found in the host

nigra (Fig. 2). Confocal microscopy confirmed that

inclusions were localized to grafted TH-positive dopa-

minergic cells. Lewy neurites were rarely encountered.

This staining pattern was similar within grafts bilater-

ally. Staining for CD45 cells demonstrated robust

expression, but was more marked on the right side

(data not shown).

DISCUSSION

This case demonstrates that dopamine neurons

implanted into the striatum of a patient with PD can

survive and reinnervate the striatum as we and others

have previously reported.1–3,5–7 Indeed, this observa-

tion has given hope to the concept that dopamine

transplantation strategies might prove beneficial for

patients with PD. It is now becoming clear, however,

that at least after some period of time, fetal nigral cells

implanted into the brain of patients with PD can

undergo the classical pathological changes of the disor-

der; namely, loss of DAT,8 loss of TH,9 and Lewy

body formation (e.g., Refs. 1–3). There can be no

doubt that these were grafted cells as they were located

within the graft borders within the striatum, contained

neuromelanin, displayed morphologic features of nigral

neurons and did not resemble endogenous striatal do-

pamine neurons. This observation confirms two previ-

ous reports which demonstrate similar PD pathology in

FIG. 2. Low- and high-power photomicrographs through the transplant stained for (A,B) alpha-synuclein, (D,E) ubiquitin, and (G,H) thioflavin-Swhich are morphologically indistinguishable from nigral neurons stained for (C) alphasynuclein, (F) ubiquitin, and (I) thioflavin-S in the hostnigra. Scale bar in I represents the following magnifications: A, D 5 160 lm; 5 lm for B, C, E, and F 5 5 lm; G 5 80 lm, and H, I 5 12 lm.

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Movement Disorders, Vol. 23, No. 16, 2008

patients undergoing postmortem examination �1 dec-

ade after transplantation.1,2 These phenotypic and mor-

phological changes also raise the possibility that these

cells were dysfunctional and might thereby account for

why transplantation has, to date, failed to provide ben-

efit in double blind clinical trials.

It is interesting to speculate on why these pathologi-

cal changes might have developed. The most parsimo-

nious explanation is that PD is an ongoing process that

can affect dopaminergic neurons despite their relatively

young age and ectopic location. It is noteworthy that

the classical changes of PD were found in implanted

neurons that were only 10 to 16 years of age and

would not be expected to manifest any of these

changes on the basis of normal aging alone. Alterna-

tively, it is possible that cell injury from some other

pathogenic factor might have damaged these implanted

cells and reproduced PD pathology but as a conse-

quence of an alternate etiology. In this regard, it is

noteworthy that there is evidence of increased CD45

expression and that it is more pronounced on the side

that was more affected. CD45 is a protein tyrosine

phosphatase, which has been shown to be an essential

regulator of T- and B-cell antigen receptor signaling. It

functions through either direct interaction with compo-

nents of the antigen receptor complexes, or by activat-

ing various Src family kinases required for the antigen

receptor signaling. Thus, we use this antibody as a

general marker of an immune response. It is also inter-

esting to note that implanted neurons were derived

from four different donors that were unrelated to the

recipient. This indicates that PD changes can develop

in neurons solely as a consequence of their environ-

ment and indicates that genetic factors are not required

in order for these changes to become manifest.

This case illustrates several other important features.

Firstly, Reduced DAT staining was seen bilaterally and

was much more pronounced than the reduction seen in

TH staining. This is similar to what we observed in

our previous case and suggests that this may represent

an earlier manifestation of dopaminergic injury and

may occur as a compensatory response to reduced do-

paminergic transmission over time. Indeed, DAT

serves to facilitate reuptake of dopamine from the syn-

apse and decreased DAT in grafted neurons may be a

response intended to enhance functional dopamine at

the synapse. On the other hand, staining for VMAT

was preserved in both of our cases suggesting that it is

a less sensitive index of cell injury than either TH or

DAT. This has important implications for brain imag-

ing of patients with PD and should be pursued.

In conclusion, although this is a single case report it

confirms that implanted cells can undergo neurodege-

nerative change in patients with PD and has important

implications for both PD pathogenesis and the future

of cell replacement therapies.

REFERENCES

1. Kordower JH, Chu Y, Hauser RA, Freeman TB, Olanow CW.Lewy body-like pathology in long-term embryonic nigral trans-plants in Parkinson’s disease. Nat Med 2008;14:504–506.

2. Li JY, Englund E, Holton JL, et al. Lewy bodies in grafted neu-rons in subjects with Parkinson’s disease suggest host-to-graftdisease propagation. Nat Med 2008;14:501–503.

3. Mendez I, Vinuela A, Astradsson A, et al. Dopamine neuronsimplanted into people with Parkinson’s disease survive withoutpathology for 14 years. Nat Med 2008;14:507–509.

4. Hauser RA, Freeman TB, Snow BJ, et al. Long-term evaluationof bilateral fetal nigral transplantation in Parkinson’s disease.Arch Neurol 1999;56:179–187.

5. Kordower JH, Rosenstein JM, Collier TJ, et al. Functional fetalnigral grafts in a patient with Parkinson’s disease: chemoana-tomic, ultrastructural, and metabolic studies. J Comp Neurol1996;370:203–230.

6. Kordower JH, Styren S, Clarke M, DeKosky ST, Olanow CW,Freeman TB. Fetal grafting for Parkinson’s disease: expression ofimmune markers in two patients with functional fetal nigralimplants. Cell Transplant 1997;6:213–219.

7. Mendez I, Sanchez-Pernaute R, Cooper O, et al. Cell type analy-sis of functional fetal dopamine cell suspension transplants in thestriatum and substantia nigra of patients with Parkinson’s disease.Brain 2005;28(Part 7):1498–1510.

8. Panzacchi A, Moresco RM, Garibotto V, et al. A voxel-basedPET study of dopamine transporters in Parkinson’s disease: rele-vance of age at onset. Neurobiol Dis 2008;31:102–109.

9. Chu Y, Le W, Kompoliti K, Jancovic J, Mufson EJ, KordowerJH. Nurr1 in Parkinson’s disease and related disorders. J CompNeurol 2006;494:495–514.

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