Autologous CD117+ Progenitor Cell Mobilization for Lung Transplantation

The investigators have developed a new therapy utilizing a stem cell found in the bone marrow
that is defined by cell surface expression of the protein "cluster of differentiation antigen
117" (CD117). Studies utilizing these stem cells in a mouse heart transplant model have
demonstrated significantly improved survival of transplanted hearts, (as much as more than 5
times that seen with untreated heart transplants). In vitro studies in mice also show that
these cells work to inhibit the immune system by inhibiting T cell activation/proliferation
by both paracrine (primary) and contact-dependent (lesser) mechanisms. Importantly, these
stem cells are taken from the intended transplant recipient (autologous) and since these
cells are part of their own body normally (in small numbers); these cells are theoretically
without risk to the patient. This is very different from other stem cell therapies, which are
taken from the donor and as such put the patient at significant risk of developing
potentially life-threatening immune reactions. Because the use of our own stem cells is
potentially safe - the rapid study, development, and implementation of autologous CD117 stem
cell (SC) therapy in human transplant patients is theoretically possible. Therefore, these
cells have high impact potential for the field of tissue and organ transplantation as well as
auto-immunity - to potentially improve tissue/cellular engraftment, decrease acute rejection,
and/or to promote organ transplant tolerance (lack of rejection despite no concomitant
immune-suppression). Prior to full clinical development (efficacy trials in humans), the next
step is to develop a safe and efficacious means for obtaining relatively large quantities of
these cells from potential human recipients. As bone marrow biopsy for cell capture is not
without risk (especially to ill potential lung transplant recipients), the investigators
propose to use Plerixafor (Mozobil), a CXC-chemokine receptor 4 (CXCR4)-inhibitor to cause
efflux of bone marrow-derived CD117+ cells to the peripheral blood for capture by
apheresis/positive selection. If successful, the next step will be to perform initial safety
studies in human patients awaiting transplantation and normal controls (not a goal of this
initial protocol however). These studies have the potential to lead to large-scale clinical
efficacy trials and ultimate indication/implementation for human disease(s).

Primary Outcome Measure: The number of circulating CD117+ cells per milliliter (ml) of
peripheral blood at baseline and following Plerixafor (Mozobil) treatment (change in
peripheral blood CD117+ cells per ml).

Secondary Outcome Measures:

i.) The number of Plerixafor (Mozobil) related adverse events (AEs). ii.) The number of
patients with Plerixafor (Mozobil) related AEs iii.) The number of Plerixafor (Mozobil)
related serious adverse events (SAEs). iv.) The number of patients with Plerixafor (Mozobil)
related serious adverse events (SAEs).

As listed in the package insert, the most common adverse reactions (≥10%) during
hematopoietic stem cell mobilization were: diarrhea (37%), nausea (34%), fatigue (27%),
injection site reaction (34%), headache (22%), arthralgia (13%), dizziness (11%), and
vomiting (10%). It should be noted that the majority of these occurred in patients also
undergoing apheresis.

Outcome Measure Time Frame:

Primary Outcome Measure Time Frame: At baseline and at 8 hours post-Plerixafor (Mozobil)
treatment

Secondary Outcome Measures Time Frame:

i.): Continuously for the first 30 minutes post-Plerixafor (Mozobil) treatment, at 1 week
post-Plerixafor (Mozobil) treatment, and up to 1 year post treatment.

ii.): For the first 30 minutes post administration, at 1 week post-Plerixafor (Mozobil)
treatment and up to 1 year post treatment, at 1 week post-Plerixafor (Mozobil) treatment, and
up to 1 year post treatment.

iii.): For the first 30 minutes post administration, at 1 week post-Plerixafor (Mozobil)
treatment and up to 1 year post treatment, at 1 week post-Plerixafor (Mozobil) treatment, and
up to 1 year post treatment.

iv.): For the first 30 minutes post administration, at 1 week post-Plerixafor (Mozobil)
treatment and up to 1 year post treatment, at 1 week post-Plerixafor (Mozobil) treatment, and
up to 1 year post treatment.

Primary Study Goals:

To determine whether Plerixafor (Mozobil) will mobilize CD117+ progenitor cells from the bone
marrow in patients with chronic lung diseases on the lung transplant waiting list (versus
normal controls). We will compare baseline counts of CD117+ cells with cell counts 8 hrs
after Plerixafor to determine the efficacy of mobilization.

The primary results will be used to determine the number of rounds of apheresis that may be
required to isolate sufficient cells for reinfusion at later timepoints in a future study.

Significance:

If the investigators can mobilize a sufficient number of autologous CD117+ cells, they will
eventually re-infuse them at the time of transplant to determine whether we can abrogate
acute rejection following human lung transplantation (future study). The investigators
believe these are safer than allogeneic stem cells as there is no risk for graft versus host
disease (GVHD) with autologous cells.

Hypothesis:

These experiments should demonstrate the effectiveness of CD117+ stem cell mobilization from
the bone marrow to the peripheral blood (PB) via CXCR4 antagonism (Plerixafor) and whether
end-stage lung disease affects the ability to mobilize stem cells. Additionally, these
results will be used to mathematically extrapolate approximately how many rounds of
peripheral blood apheresis will be required to attain adequate stem cell numbers for clinical
infusion (10e7) for a future study.

Methods:

Experiments will involve taking blood from consented patients awaiting lung transplantation
(as well as normal controls) prior to Plerixafor (Mozobil) treatment (240mcg/kg
subcutaneously) and then 8 hours after treatment as in Table 1.

TABLE 1:

Patient Category PB baseline analysis Plerixafor (Mozobil) Rx PB analysis 8hrs post-Rx

Awaiting Tx (n=15, 5 chronic obstructive pulmonary disease (COPD), 5 Cystic Fibrosis (CF),
and 5 Pulmonary Fibrosis (PF)) CD117 isolation/analysis by Flow Cytometry Yes - 240 mcg/kg
CD117+ stem cell isolation/analysis by Flow Cytometry

Normal Control (n=5) CD117 isolation/analysis by Flow Cytometry Yes - 240mcg/kg CD117+ stem
cell isolation/analysis by Flow Cytometry

Inclusion Criteria:

- Patients on the Univ. of Colorado Lung Transplant Waiting List Age 18 to 70 years old
Ability to sign and understand informed consent

- Patients 18 years or older up to age 70 on the University of Colorado Lung Transplant
Waiting List and normal control subjects will be eligible for enrollment. Patients
will include those with Chronic Obstructive Lung Disease, Pulmonary Fibrosis and
Cystic Fibrosis

Normal control subjects = 5

Lung Transplant waitlist patients = 15 (5 each with COPD, PF or CF to determine whether
disease affects mobilization potential)

Exclusion Criteria:

- Subject has already undergone lung transplantation.

- Subject has a known or suspected allergy to Plerixafor.

- Women of child-bearing age who are unwilling to use appropriate birth control to
prevent becoming pregnant.

- Subjects who have received an investigational agent or device within 30 days of
administration of the study agent. For the purposes of this trial, an investigational
agent or device is any which is implemented under an Investigational New Drug
Application (IND).

- Subjects with a history of Hepatitis B or C.

- Subjects with significant anemia (HCT < 35),thrombocytopenia (Plt count <100,000/cc),
leukocytosis (WBC > 12,000/cc), or leucopenia (WBC < 5,000/cc).

- Subjects with splenomegaly.

- Subjects unable to comply with all protocol requirements.