Cell assessments
The extracted cells had the same characteristics as the cells we used in our previous study (13). Cells isolated from the sural nerve were positive for S-100 marker, which indicated that these cells had the properties of SCs (Fig. 1.a). MSCs were positive for CD73 and CD 105 and negative for CD45 and CD34 in flow cytometry analysis (Fig. 1.b).
Adverse events
Several mild adverse events were observed among the patients. Increasing in spasticity, numbness, or tingling sensation and neuropathic pain was reported by 5, 4, and 2 out of 11 patients, respectively. Headache and facial flushing appeared in two patients after transplantation that was resolved spontaneously. Furthermore, none of the patients reported fever after injection (Table 2).
Other systemic complications such as anaphylactic shock, hypersensitivities, rush, or inflammation were not observed. Infectious complications associated with transplantation-like meningitis were not evident in the study.
Although previous spinal instrumentation caused some worst effects on the visibility of images in the patients, MRI indicated no neoplastic overgrowth, syringomyelia, or pseudo-meningocele after transplantation (Fig. 2).
ASIA evaluation
Sensory and/or motor improvement was evident in 9 patients according to ASIA assessment. Six patients experienced positive sensory changes and four patients had motor recovery (Table 1). In our assessment, the cervical SCI patients showed more improvement rate in motor aspects (75% of the cervical and 14% of the lumbar-thoracic patients had motor improvement) and lumbar-thoracic SCI patients experienced more improvement rate in sensory ASIA score (63% of the lumbar-thoracic and 50% of the cervical patients had sensory improvement) (Fig. 3).
In terms of the intensity of the changes, light touch ASIA score alterations were approximately the same as the pinprick changes (11.6±13.1 and 12±13, respectively) and both were more than the motor score alterations (9.5±3.3). Light touch score among all the patients improved significantly after 6 and 12 months in comparison with pre-transplantation scores (p-value = 0.042 and 0.027, respectively). Score differences between 6th and 12th months were not significant (p-value = 0.317). For pinprick, the results were the same as the light touch changes (p-value = 0.041, 0.027, and 0.317, respectively). The difference between the motor score in pre-transplantation evaluation and 6- and 12-months follow up was not significant (p-value = 0.068 and 0.066, respectively) (Fig. 3, Table 3).
Table 3. ASIA and SCIM III scores at different time points.
|
Score Subject
|
Population
|
Time
|
Mean
|
SD
|
P-value
|
ASIA
|
Motor Score
|
Total Study Population
|
Before Injection
|
37.54
|
17.58
|
-
|
After 6 months
|
40.45
|
14.80
|
0.068
|
After 12 months
|
41.00
|
14.58
|
0.066
|
Thoracic Patients
|
Before Injection
|
50.00
|
00.00
|
-
|
After 6 months
|
51.00
|
2.64
|
0.317
|
After 12 months
|
51.28
|
3.40
|
0.317
|
Cervical Patients
|
Before Injection
|
15.75
|
5.90
|
-
|
After 6 months
|
22.00
|
1.63
|
0.109
|
After 12 months
|
23.00
|
2.58
|
0.109
|
Light Touch
|
Total Study Population
|
Before Injection
|
47.63
|
24.37
|
-
|
After 6 months
|
50.54
|
24.46
|
0.042*
|
After 12 months
|
51.80
|
25.74
|
0.027*
|
Thoracic Patients
|
Before Injection
|
60.57
|
19.51
|
-
|
After 6 months
|
63.71
|
17.12
|
0.109
|
After 12 months
|
68.00
|
16.44
|
0.068
|
Cervical Patients
|
Before Injection
|
25.00
|
12.05
|
-
|
After 6 months
|
27.50
|
15.00
|
0.180
|
After 12 months
|
27.50
|
15.00
|
0.180
|
Pin Prick
|
Total Study Population
|
Before Injection
|
48.54
|
25.66
|
-
|
After 6 months
|
51.63
|
25.71
|
0.041*
|
After 12 months
|
53.00
|
27.00
|
0.027*
|
Thoracic Patients
|
Before Injection
|
62.00
|
20.81
|
-
|
After 6 months
|
65.42
|
19.13
|
0.102
|
After 12 months
|
70.00
|
17.15
|
0.066
|
Cervical Patients
|
Before Injection
|
25.00
|
12.09
|
-
|
After 6 months
|
27.50
|
15.86
|
0.180
|
After 12 months
|
27.50
|
15.86
|
0.180
|
SCIM III
|
Total Score
|
Total Study Population
|
Before Injection
|
28.9
|
12.99
|
-
|
After 6 months
|
37.54
|
18.40
|
0.012*
|
After 12 months
|
43.10
|
25.77
|
0.018*
|
Thoracic Patients
|
Before Injection
|
37.14
|
6.28
|
-
|
After 6 months
|
49.28
|
7.08
|
0.018*
|
After 12 months
|
60.50
|
14.18
|
0.028*
|
Cervical Patients
|
Before Injection
|
14.50
|
7.00
|
-
|
After 6 months
|
17.00
|
12.00
|
0.317
|
After 12 months
|
17.00
|
12. 00
|
0.317
|
Self-Care
|
Total Study Population
|
Before Injection
|
8.00
|
5.53
|
-
|
After 6 months
|
10.36
|
6.74
|
0.043*
|
After 12 months
|
11.40
|
7.93
|
0.005**
|
Thoracic Patients
|
Before Injection
|
11.71
|
2.49
|
-
|
After 6 months
|
14.71
|
2.98
|
0.068
|
After 12 months
|
17.16
|
2.48
|
0.042*
|
Cervical Patients
|
Before Injection
|
1.50
|
1.00
|
-
|
After 6 months
|
2.75
|
3.50
|
0.317
|
After 12 months
|
2.75
|
3.50
|
0.317
|
Respiration and Sphincter Management
|
Total Study Population
|
Before Injection
|
17.18
|
5.89
|
-
|
After 6 months
|
21.72
|
8.22
|
0.016*
|
After 12 months
|
26.20
|
13.63
|
0.027*
|
Thoracic Patients
|
Before Injection
|
19.57
|
4.64
|
-
|
After 6 months
|
26.00
|
4.24
|
0.026*
|
After 12 months
|
34.16
|
10.04
|
0.043*
|
Cervical Patients
|
Before Injection
|
13.00
|
6.00
|
-
|
After 6 months
|
14.25
|
8.50
|
0.317
|
After 12 months
|
14.25
|
8.50
|
0.317
|
Mobility
|
Total Study Population
|
Before Injection
|
3.72
|
3.58
|
-
|
After 6 months
|
5.45
|
4.78
|
0.039*
|
After 12 months
|
8.90
|
12.81
|
0.043*
|
Thoracic Patients
|
Before Injection
|
5.85
|
2.60
|
-
|
After 6 months
|
8.57
|
2.63
|
0.039*
|
After 12 months
|
14.83
|
13.77
|
0.043*
|
Cervical Patients
|
Before Injection
|
0.00
|
0.00
|
-
|
After 6 months
|
0.00
|
0.00
|
1.00
|
After 12 months
|
0.00
|
0.00
|
1.00
|
Bold values indicate statistical significance ( * = P-value ≤ 0.05; ** P-value ≤ 0.01).
|
SCIM III changes
Regarding our SCIM III assessment, 8 out of 11 patients had some degrees of functional recovery, most of which were thoracic SCI patients. So, all the thoracic SCI patients experienced a positive change in SCIM III evaluation (Table 1). Among the cervical SCI patients, only one patient (number 8) had improvement in the "sphincter management-bladder" item. Mean ± SD of the SCIM III changes was 21.2±13.3 and, among the SCIM III sub-scores, “respiration and sphincter management” (15±9.9), “mobility” (9.5±13.3), and “self-care” (6±1.4) comprised the most of the score changes (Fig. 4).
Statistical analysis revealed that the patients experienced significant progressive changes after each 6 months in SCIM III total score and its sub-scales (Fig. 4). Differences between the pre- and post-transplantation groups and between each post-transplantation group (cervical and thoracolumbar) were significant in total SCIM III score, respiration and sphincter management, mobility, and self-care (p-value of changes after 6 months were 0.012, 0.043, 0.016, and 0.039 and, for changes after 12 months, were 0.018, 0.005, 0.027, and 0.043, respectively). In thoracolumbar patients, our statistical evaluation revealed that the differences between pre-transplantation and 6 and 12 months were significant (except self-care changes after 6 months, which was not significant). P-value for changes of SCIM III score in thoracolumbar SCI patients after 6 and 12 months were 0.018 and 0.028, respectively (Table 3).
Subjective outcomes
Our findings supported that the most remarkable positive, subjective improvement was in the trunk movement (in 8 patients) and equilibrium in standing/sitting positions (in 7 patients). Furthermore, three patients (patients with numbers 1, 3, and 5) experienced a reduction in the severity of constipation. We also observed that the two of our patients (numbers 1 and 9) claimed that they obtained the sensation of the filling bladder and rectum in 6th and 12th months of their follow-up (patient number 1 acquired sense of rectal filling in 12th months of follow-up). Furthermore, one patient had successful changes as the empowerment of voiding (patient number 5) (Table 2).
UDS assessment of patient number 5 also supported this change. Pre-transplantation UDS of the patient revealed the presence of uninhibited contraction (no voiding), maximum detrusor pressure of 55cmH2O, maximum flow during cytometry less than 1cc/sec, and post-voiding residue of 314 cc. Post-transplantation UDS changed to maximum detrusor pressure of 15 cmH2O, maximum flow during cytometry of 3.3 cc/sec, post-voiding residue of 410 cc, and voided volume of 40cc.