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                                                                   EXHIBIT 10.37

                          REGISTRATION RIGHTS AGREEMENT
                 (Series 2001 12% Convertible Promissory Notes)

     REGISTRATION RIGHTS AGREEMENT (this "AGREEMENT"), dated as of April 23,
2001, by CYTOMEDIX, INC., a Delaware corporation, with its headquarters located
at Three Parkway North, Deerfield, Illinois 60015 (the "COMPANY"), for the
benefit of the purchasers of the Company's Series 2001 12% Convertible
Promissory Notes described on EXHIBIT "A" attached hereto and made a part hereof
(together with any assignee or transferee of all of their respective
registration rights hereunder, the "NOTE INVESTORS").

     WHEREAS:

     A. In connection with the Investors' acquisition of Securities Purchase
Agreement by and among the parties hereto of even date herewith (the "SECURITIES
PURCHASE AGREEMENT"), the Company has agreed, upon the terms and subject to the
conditions contained therein, to issue and sell to the Note Investors Series
2001 12% Convertible Promissory Notes in the aggregate principal amount of
$1,807,500 (the "NOTES") that are convertible into shares of the Company's
common stock (the "COMMON STOCK"), upon the terms and subject to the limitations
and conditions set forth in such Notes; and

     B. To induce the Note Investors to execute and deliver the Securities
Purchase Agreement, the Company has agreed to provide certain registration
rights under the Securities Act of 1933, as amended, and the rules and
regulations thereunder, or any similar successor statute (collectively, the
"1933 ACT"), and applicable state securities laws;

     NOW, THEREFORE, in consideration of the premises and the mutual covenants
contained herein and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Company and each of the Note
Investors hereby agree as follows:

     1.   DEFINITIONS.

          a.   As used in this Agreement, the following terms shall have the
following meanings:

               (i)  "INVESTORS" means the Note Investors and any
transferee or assignee who agrees to become bound by the provisions of this
Agreement in accordance with Section 9 hereof.

               (ii) "REGISTER," "REGISTERED," and "REGISTRATION" refer to a
registration effected by preparing and filing a Registration Statement or
Statements in compliance with the 1933 Act and pursuant to Rule 415 under the
1933 Act or any successor rule providing for offering securities on a continuous
basis ("RULE 415"), and the declaration or ordering of effectiveness of such
Registration Statement by the United States Securities and Exchange Commission
(the "SEC").

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               (iii) "REGISTRABLE SECURITIES" means the Conversion Shares issued
or issuable upon conversion or otherwise pursuant to the Notes (as defined in
the Note)issued or issuable and shares of Common Stock issued or issuable in
respect of interest or in redemption of the Notes in accordance with the terms
thereof and any shares of Common Stock issued or issuable as a dividend on or in
exchange for or otherwise with respect to any of the foregoing, PROVIDED, that
any shares of Common Stock which have been sold pursuant to a Registration
Statement or which may be sold without registration or restriction (including
volume limitations) shall cease to be Registrable Securities hereunder.

               (iv) "REGISTRATION STATEMENT" means a registration statement of
the Company under the 1933 Act.

          b.   Capitalized terms used herein and not otherwise defined herein
shall have the respective meanings set forth in the Securities Purchase
Agreement or Note.

     2.   REGISTRATION.

          a.   MANDATORY REGISTRATION. The Company shall prepare, and, on or
prior to the date which is prior to the first anniversary of the Closing Date
(the "FILING DATE"), file with the SEC a Registration Statement on Form S-3 (or,
if Form S-3 is not then available, on such form of Registration Statement as is
then available to effect a registration of the Registrable Securities, subject
to the consent of the Note Investors, which consent will not be unreasonably
withheld) covering the resale of the Registrable Securities underlying the Notes
issued or issuable pursuant to the Securities Purchase Agreement, which
Registration Statement, to the extent allowable under the 1933 Act and the rules
and regulations promulgated thereunder (including Rule 416), shall state that
such Registration Statement also covers such indeterminate number of additional
shares of Common Stock as may become issuable upon conversion of the Notes (i)
to prevent dilution resulting from stock splits, stock dividends or similar
transactions or (ii) by reason of changes in the Conversion Price of the Notes
in accordance with the terms thereof. The number of shares of Common Stock
initially included in such Registration Statement shall be no less than two (2)
times the sum of the number of Conversion Shares that are then issuable upon
conversion of the Notes, without regard to any limitation on the Investor's
ability to convert the Notes. The Company acknowledges that the number of shares
initially included in the Registration Statement represents a good faith
estimate of the maximum number of shares issuable upon conversion of the Notes.

          b.   UNDERWRITTEN OFFERING. If any offering pursuant to a Registration
Statement pursuant to Section 2(a) hereof involves an underwritten offering, the
Investors who hold a majority in interest of the Registrable Securities subject
to such underwritten offering, with the consent of at least seventy-five percent
(75%) of the Note Investors, shall have the right to select one legal counsel
and, subject to the approval of the Company, not to be unreasonably withheld, an
investment banker or bankers and manager or managers to administer the offering.


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          c.   PIGGY-BACK REGISTRATIONS. If at any time prior to the expiration
of the Registration Period (as hereinafter defined) the Company shall determine
to file with the SEC a Registration Statement relating to an offering for its
own account or the account of others under the 1933 Act of any of its equity
securities (other than on Form S-4 or Form S-8 or their then equivalents
relating to equity securities to be issued solely in connection with any
acquisition of any entity or business, a corporate reorganization or other
transaction on Form S-4, a registration on any form that does not permit
secondary sales or equity securities issuable in connection with stock option or
other employee benefit plans), the Company shall send to each Investor who is
entitled to registration rights under this Section 2(c) written notice of such
determination and, if within ten (10) business days after the effective date of
such notice, such Investor shall so request in writing, the Company shall
include in such Registration Statement all or any part of the Registrable
Securities such Investor requests to be registered. No right to registration of
Registrable Securities under this Section 2(c) shall be construed to limit any
registration required under Section 2(a) hereof. If an offering in connection
with which an Investor is entitled to registration under this Section 2(c) is an
underwritten offering, then each Investor whose Registrable Securities are
included in such Registration Statement shall, unless otherwise agreed by the
Company, offer and sell such Registrable Securities in an underwritten offering
using the same underwriter or underwriters and, subject to the provisions of
this Agreement, on the same terms and conditions as other shares of Common Stock
included in such underwritten offering.

          d.   ELIGIBILITY FOR FORM SB-2 OR FORM S-1: CONVERSION TO FORM S-3.
The Company represents and warrants that it meets the requirements for the use
of Form SB-2 or Form S-1 for registration of the sale by the Note Investors and
any other Investors of the Registrable Securities. The Company agrees to file
all reports required to be filed by the Company with the SEC in a timely manner
so as to become eligible, and thereafter to maintain its eligibility, for the
use of Form S-3. Not later than ten (10) business days after the Company first
meets the registration eligibility and transaction requirements for the use of
Form S-3 (or any successor form) for registration of the offer and sale by the
Note Investors and any other Investors of Registrable Securities, the Company
shall file a Registration Statement on Form S-3 (or such successor form) with
respect to the Registrable Securities covered by the Registration Statement on
Form SB-2 or Form S-1, whichever is applicable, filed pursuant to Section 2(a)
(and include in such Registration Statement on Form S-3 the information required
by Rule 429 under the 1933 Act) or convert the Registration Statement on Form
SB-2 or Form S-1, whichever is applicable, filed pursuant to Section 2(a) to a
Form S-3 pursuant to Rule 429 under the 1933 Act and use its best efforts to
have such Registration Statement (or such amendment) declared effective as soon
as reasonably practicable thereafter.

     3.   OBLIGATIONS OF THE COMPANY. In connection with the registration of the
Registrable Securities, the Company shall have the following obligations:

          a.   The Company shall prepare promptly, and file with the SEC not
later than the Filing Date, a Registration Statement with respect to the number
of Registrable Securities provided in Section 2(a), and thereafter use its best
efforts to cause such Registration Statement relating to Registrable Securities
to become effective as soon as possible after such filing but in


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no event later than the first anniversary of the Closing Date), and keep the
Registration Statement effective pursuant to Rule 415 at all times until such
date as is the earlier of (i) the date on which all of the Registrable
Securities have been sold and (ii) the date on which the Registrable Securities
(in the opinion of counsel to the Note Investors) may be immediately sold to the
public without registration or restriction (including without limitation as to
volume by each holder thereof) under the 1933 Act (the "REGISTRATION PERIOD"),
which Registration Statement (including any amendments or supplements thereto
and prospectuses contained therein) shall not contain any untrue statement of a
material fact or omit to state a material fact required to be stated therein, or
necessary to make the statements therein, in light of the circumstances, under
which they were made, not misleading.

          b.   The Company shall prepare and file with the SEC such amendments
(including post-effective amendments) and supplements to the Registration
Statements and the prospectus used in connection with the Registration
Statements as may be necessary to keep the Registration Statements effective at
all times during the Registration Period, and, during such period, comply with
the provisions of the 1933 Act with respect to the disposition of all
Registrable Securities of the Company covered by the Registration Statements
until such time as all of such Registrable Securities have been disposed of in
accordance with the intended methods of disposition by the seller or sellers
thereof as set forth in the Registration Statements. In the event the number of
shares available under a Registration Statement filed pursuant to this Agreement
is insufficient to cover all of the Registrable Securities issued or issuable
upon conversion of the Notes, the Company shall amend the Registration
Statement, or file a new Registration Statement (on the short form available
therefore, if applicable), or both, so as to cover all of the Registrable
Securities, in each case, as soon as practicable, but in any event within twenty
(20) business days after the necessity therefor arises (based on the market
price of the Common Stock and other relevant factors on which the Company
reasonably elects to rely). The Company shall use its best efforts to cause such
amendment and/or new Registration Statement to become effective as soon as
practicable following the filing thereof. The provisions of Section 2(c) above
shall be applicable with respect to such obligation, with the one hundred twenty
(120) days running from the day after the date on which the Company reasonably
first determines (or reasonably should have determined) the need therefor.

          c.   The Company shall furnish to each Investor whose Registrable
Securities are included in a Registration Statement and its legal counsel (i)
promptly (but in no event more than three (3) business days) after the same is
prepared and publicly distributed, filed with the SEC, or received by the
Company, one copy of each Registration Statement and any amendment thereto, each
preliminary prospectus and prospectus and each amendment or supplement thereto,
and, in the case of the Registration Statement referred to in Section 2(a), each
letter written by or on behalf of the Company to the SEC or the staff of the
SEC, and each item of correspondence from the SEC or the staff of the SEC, in
each case relating to such Registration Statement (other than any portion of any
thereof which contains information for which the Company has sought confidential
treatment), and (ii) such number of copies of a prospectus, including a
preliminary prospectus, and all amendments and supplements thereto and such
other documents as such Investor may reasonably request in order to facilitate
the disposition of the Registrable Securities

<PAGE>

owned by such Investor in accordance with the Registration Statement. The
Company will promptly notify each Investor by facsimile of the effectiveness of
each Registration Statement or any post-effective amendment. The Company will
promptly respond to any and all comments received from the SEC (which comments
shall promptly be made available to the Investors upon request, unless they
relate to information for which the Company has sought confidential treatment),
with a view towards causing each Registration Statement or any amendment thereto
to be declared effective by the SEC as soon as practicable, shall promptly file
an acceleration request as soon as practicable (but in no event more than two
(2) business days) following the resolution or clearance of all SEC comments or,
if applicable, following notification by the SEC that any such Registration
Statement or any amendment thereto will not be subject to review and shall
promptly file with the SEC a final prospectus as soon as practicable (but in no
event more than two (2) business days) following receipt by the Company from the
SEC of an order declaring the Registration Statement effective.

          d.   The Company shall use reasonable efforts to (i) register and
qualify the Registrable Securities covered by the Registration Statements under
such other securities or "blue sky" laws of such jurisdictions in the United
States as the Investors who hold at least seventy-five percent (75%) of the
Registrable Securities being offered reasonably request, (ii) prepare and file
in those jurisdictions such amendments (including post-effective amendments) and
supplements to such registrations and qualifications as may be necessary to
maintain the effectiveness thereof during the Registration Period, (iii) take
such other actions as may be necessary to maintain such registrations and
qualifications in effect at all times during the Registration Period, and (iv)
take all other actions reasonably necessary or advisable to qualify the
Registrable Securities for sale in such jurisdictions; PROVIDED, HOWEVER, that
the Company shall not be required in connection therewith or as a condition
thereto to (a) qualify to do business in any jurisdiction where it would not
otherwise be required to qualify but for this Section 3(d), (b) subject itself
to general taxation in any such jurisdiction, (c) file a general consent to
service of process in any such jurisdiction, (d) provide any undertakings that
cause the Company undue expense or burden, or (e) make any change in its charter
or bylaws, which in each case the Board of Directors of the Company determines
to be contrary to the best interests of the Company and its stockholders.

          e.   In the event the requisite number of Investors (with the approval
of the requisite Note Investors) select underwriters for the offering, subject
to the Company's approval rights pursuant to Section 1(c), the Company shall
enter into and perform its obligations under an underwriting agreement, in usual
and customary form, including, without limitation, customary indemnification and
contribution obligations, with the underwriters of such offering.

          f.   As promptly as practicable after becoming aware of such event,
the Company shall notify each Investor of the happening of any event, of which
the Company has knowledge, as a result of which the prospectus included in any
Registration Statement, as then in effect, includes an untrue statement of a
material fact or omission to state a material fact required to be stated therein
or necessary to make the statements therein, in light of the circumstances under
which they were made, not misleading, and use its best efforts promptly to
prepare a supplement or amendment to any Registration Statement to correct such
untrue statement or


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omission, and deliver such number of copies of such supplement or amendment to
each Investor as such Investor may reasonably request.

          g.   The Company shall use its reasonable best efforts to prevent the
issuance of any stop order or other suspension of effectiveness of any
Registration Statement, and, if such an order is issued, to obtain the
withdrawal of such order at the earliest possible moment and to notify each
Investor who holds Registrable Securities being sold (or, in the event of an
underwritten offering, the managing underwriters) of the issuance of such order
and the resolution thereof.

          h.   The Company shall permit a single firm of counsel designated by
the Note Investors to review such Registration Statement and all amendments and
supplements thereto (as well as all requests for acceleration or effectiveness
thereof) a reasonable period of time prior to their filing with the SEC, and not
file any document in a form to which such counsel reasonably objects and will
not request acceleration of such Registration Statement without prior notice to
such counsel. The sections of such Registration Statement covering information
with respect to the Investors, the Investor's beneficial ownership of securities
of the Company or the Investors intended method of disposition of Registrable
Securities shall conform to the information provided to the Company by each of
the Investors, except to the extent violative of applicable law.

          i.   The Company shall hold in confidence and not make any disclosure
of information concerning an Investor provided to the Company unless (i)
disclosure of such information is necessary to comply with federal or state
securities laws, (ii) the disclosure of such information is necessary to avoid
or correct a misstatement or omission in any Registration Statement, (iii) the
release of such information is ordered pursuant to a subpoena or other order
from a court or governmental body of competent jurisdiction, or (iv) such
information has been made generally available to the public other than by
disclosure in violation of this or any other agreement. The Company agrees that
it shall, upon learning that disclosure of such information concerning an
Investor is sought in or by a court or governmental body of competent
jurisdiction or through other means, give prompt notice to such Investor prior
to making such disclosure, and allow the Investor, at its expense, to undertake
appropriate action to prevent disclosure of, or to obtain a protective order
for, such information.

          j.   The Company shall (i) cause all the Registrable Securities
covered by the Registration Statement to be listed on each national securities
exchange on which securities of the same class or series issued by the Company
are then listed, if any, if the listing of such Registrable Securities is then
permitted under the rules of such exchange, or (ii) to the extent the securities
of the same class or series are not then listed on a national securities
exchange, secure the designation and quotation, of all the Registrable
Securities covered by the Registration Statement on Nasdaq or, if not eligible
for Nasdaq, on Nasdaq SmallCap or, if not eligible for Nasdaq or Nasdaq
SmallCap, on the OTC BB and, without limiting the generality of the foregoing,
to arrange for at least two market makers to register with the National
Association of Securities Dealers, Inc. ("NASD") as such with respect to such
Registrable Securities.


<PAGE>

          k.   The Company shall provide a transfer agent and registrar, which
may be a single entity, for the Registrable Securities not later than the
effective date of the Registration Statement.

          l.   At the request of the holders of at least seventy-five percent
(75%) of the Registrable Securities, the Company shall prepare and file with the
SEC such amendments (including post-effective amendments) and supplements to a
Registration Statement and any prospectus used in connection with the
Registration Statement as may be necessary in order to change the plan of
distribution set forth in such Registration Statement.

     4.   OBLIGATIONS OF THE INVESTORS. In connection with the registration of
the Registrable Securities, the Investors shall have the following obligations:

          a.   It shall be a condition precedent to the obligations of the
Company to complete the registration pursuant to this Agreement with respect to
the Registrable Securities of a particular Investor that such Investor shall
furnish to the Company such information regarding itself, the Registrable
Securities held by it and the intended method of disposition of the Registrable
Securities held by it as shall be reasonably required to effect the registration
of such Registrable Securities and shall execute such documents in connection
with such registration as the Company may reasonably request. At least three (3)
business days prior to the first anticipated filing date of the Registration
Statement, the Company shall notify each Investor of the information the Company
requires from each such Investor.

          b.   Each Investor, by such Investor's acceptance of the Registrable
Securities, agrees to cooperate with the Company as reasonably requested by the
Company in connection with the preparation and filing of the Registration
Statements hereunder, unless such Investor has notified the Company in writing
of such Investor's election to exclude all of such Investor's Registrable
Securities from the Registration Statements, except to the extent any such
requested information is required by the SEC or by applicable law to be included
in any such Registration Statement.

          c.   In the event Investors (with the approval of the Note Investors
and the Company in accordance with Section 1(c)) determine to engage the
services of an underwriter, each Investor agrees to enter into and perform such
Investor's obligations under an underwriting agreement, in usual and customary
form, including, without limitation, customary indemnification and contribution
obligations, with the managing underwriter of such offering and take such other
actions as are reasonably required in order to expedite or facilitate the
disposition of the Registrable Securities, unless such Investor has notified the
Company in writing of such Investor's election to exclude all of such Investor's
Registrable Securities from such Registration Statement.

          d.   Each Investor agrees that, upon receipt of any notice from the
Company of the happening of any event of the kind described in Section 3(g),
such Investor will immediately discontinue disposition of Registrable Securities
pursuant to the Registration Statement covering


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such Registrable Securities until such Investor's receipt of the copies of the
supplemented or amended prospectus contemplated by Section 3(g) and, if so
directed by the Company, such Investor shall deliver to the Company (at the
expense of the Company) or destroy (and deliver to the Company a certificate of
destruction) all copies in such Investor's possession, of the prospectus
covering such Registrable Securities current at the time of receipt of such
notice.

          e.   No Investor may participate in any underwritten registration
hereunder unless such Investor (i) agrees to sell such Investor's Registrable
Securities on the basis provided in any underwriting arrangements in usual and
customary form entered into by the Company, (ii) completes and executes all
questionnaires, powers of attorney, indemnities, underwriting agreements and
other documents reasonably required under the terms of such underwriting
arrangements, and (iii) agrees to pay its pro rata share of all underwriting
discounts and commissions and any expenses in excess of those payable by the
Company pursuant to Section 5 below.

     5.   EXPENSES OF REGISTRATION. All reasonable expenses, other than
underwriting discounts and commissions and stock transfer taxes, if any,
incurred in connection with registrations, filings or qualifications pursuant to
Sections 2 and 3, including, without limitation, all registration, listing and
qualification fees, printers and accounting fees, the fees and disbursements of
counsel for the Company, and the reasonable fees and disbursements of one
counsel selected by the Note Investors pursuant to Sections 2(b) and 3(h) hereof
shall be borne by the Company.

     6.   INDEMNIFICATION. In the event any Registrable Securities are included
in a Registration Statement under this Agreement:

          a.   To the extent permitted by law, the Company will indemnify, hold
harmless and defend (i) each Investor who holds such Registrable Securities,
(ii) the directors, officers, partners and each person who controls any Investor
within the meaning of the 1933 Act or the Securities Exchange Act of 1934, as
amended (the "1934 ACT"), if any, (iii) any underwriter (as defined in the 1933
Act) for the Investors, and (iv) the directors, officers, partners, employees
and each person who controls any such underwriter within the meaning of the 1933
Act or the 1934 Act, if any (each, an "INDEMNIFIED PERSON"), against any joint
or several losses, claims, damages, liabilities or expenses (collectively,
together with actions, proceedings or inquiries by any regulatory or
self-regulatory organization, whether commenced or threatened, in respect
thereof, "CLAIMS") to which any of them may become subject insofar as such
Claims arise out of or are based upon: (i) any untrue statement or alleged
untrue statement of a material fact in a Registration Statement or the omission
or alleged omission to state therein a material fact required to be stated or
necessary to make the statements therein, in light of the circumstances under
which they were made, not misleading; (ii) any untrue statement or alleged
untrue statement of a material fact contained in any preliminary prospectus if
used prior to the effective date of such Registration Statement, or contained in
the final prospectus (as amended or supplemented, if the Company files any
amendment thereof or supplement thereto with the SEC) or the omission or alleged
omission to state therein any material fact necessary to make the


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statements made therein, in light of the circumstances under which the
statements therein were made, not misleading; or (iii) any violation or alleged
violation by the Company of the 1933 Act, the 1934 Act, any other law,
including, without limitation, any state securities law, or any rule or
regulation thereunder relating to the offer or sale of the Registrable
Securities (the matters in the foregoing clauses (i) through (iii) being,
collectively, "VIOLATIONS"). Subject to the restrictions set forth in Section
6(c) with respect to the number of legal counsel, the Company shall reimburse
the Indemnified Person for any reasonable legal fees or other reasonable
expenses incurred by them in connection with investigating or defending any such
Claim. Notwithstanding anything to the contrary contained herein, the
indemnification agreement contained in this Section 6(a): (i) shall not apply to
a Claim arising out of or based upon a Violation which occurs in reliance upon
and in conformity with information furnished in writing to the Company by any
Indemnified Person or underwriter for such Indemnified Person expressly for use
in connection with the preparation of such Registration Statement or any such
amendment thereof or supplement thereto, if such prospectus was timely made
available by the Company pursuant to Section 3(c) hereof; (ii) shall not apply
to amounts paid in settlement of any Claim if such settlement is effected
without the prior written consent of the Company, which consent shall not be
unreasonably withheld; (iii) with respect to any preliminary prospectus, shall
not inure to the benefit of any Indemnified Person if the untrue statement or
omission of material fact contained in the preliminary prospectus was corrected
on a timely basis in the prospectus, as then amended or supplemented, such
corrected prospectus was timely made available by the Company pursuant to
Section 3(c) hereof, and the Indemnified Person was promptly advised in writing
not to use the incorrect prospectus prior to the use giving rise to a Violation
and such Indemnified Person, notwithstanding such advice, used it, and (iv) in
the case of gross negligence or willful misconduct by such Investor. Such
indemnity shall remain in full force and effect regardless of any investigation
made by or on behalf of the Indemnified Person and shall survive the transfer of
the Registrable Securities by the Investors pursuant to Section 9.

          b.   In connection with any Registration Statement in which an
Investor is participating, each such Investor agrees severally and not jointly
to indemnify, hold harmless and defend, to the same extent and in the same
manner set forth in Section 6(a), the Company, each of its directors, each of
its officers who signs the Registration Statement, each person, if any, who
controls the Company within the meaning of the 1933 Act or the 1934 Act, any
underwriter and any other stockholder selling securities pursuant to the
Registration Statement or any of its directors or officers or any person who
controls such stockholder or underwriter within the meaning of the 1933 Act or
the 1934 Act (collectively and together with an Indemnified Person, an
"INDEMNIFIED PARTY"), against any Claim to which any of them may become subject,
under the 1933 Act, the 1934 Act or otherwise, insofar as such Claim arises out
of or is based upon any Violation by such Investor, in each case to the extent
(and only to the extent) that such Violation occurs in reliance upon and in
conformity with written information furnished to the Company by such Investor
expressly for use in connection with such Registration Statement (or prospectus
forming a part thereof); and subject to Section 6(c) such Investor will
reimburse any legal or other expenses incurred by them in connection with
investigating or defending any such Claim; PROVIDED, HOWEVER, that the indemnity
agreement contained in this Section 6(b) shall not apply (i) to amounts paid in
settlement of any Claim if such settlement is effected without the prior


<PAGE>

written consent of such Investor, which consent shall not be unreasonably
withheld and (ii) in the case of gross negligence or willful misconduct by the
Company; PROVIDED, FURTHER, HOWEVER, that the Investor shall be liable under
this Agreement (including this Section 6(b) and Section 7) for only that amount
as does not exceed the net proceeds to such Investor as a result of the sale of
Registrable Securities pursuant to such Registration Statement. Such indemnity
shall remain in full force and effect regardless of any investigation made by or
on behalf of such Indemnified Party and shall survive the transfer of the
Registrable Securities by the Investors pursuant to Section 9. Notwithstanding
anything to the contrary contained herein, the indemnification agreement
contained in this Section 6(b) with respect to any preliminary prospectus shall
not inure to the benefit of any Indemnified Party if the untrue statement or
omission of material fact contained in the preliminary prospectus was corrected
on a timely basis in the prospectus, as then amended or supplemented.

          c.   Promptly after receipt by an Indemnified Person or Indemnified
Party under this Section 6 of notice of the commencement of any action
(including any governmental action), such Indemnified Person or Indemnified
Party shall, if a Claim in respect thereof is to be made against any
indemnifying party under this Section 6, deliver to the indemnifying party a
written notice of the commencement thereof, and the indemnifying party shall
have the right to participate in, and, to the extent the indemnifying party so
desires, jointly with any other indemnifying party similarly noticed, to assume
control of the defense thereof with counsel mutually satisfactory to the
indemnifying party and the Indemnified Person or the Indemnified Party, as the
case may be; PROVIDED, HOWEVER, that an Indemnified Person or Indemnified Party
shall have the right to retain its own counsel with the fees and expenses to be
paid by the indemnifying party, if, in the reasonable opinion of counsel
retained by the indemnifying party, the representation by such counsel of the
Indemnified Person or Indemnified Party and the indemnifying party would be
inappropriate due to actual or potential differing interests between such
Indemnified Person or Indemnified Party and any other party represented by such
counsel in such proceeding. The indemnifying party shall pay for only one
separate legal counsel for the Indemnified Persons or the Indemnified Parties,
as applicable, and such legal counsel shall be selected by Investors holding at
least seventy-five percent (75%) of the Registrable Securities included in the
Registration Statement to which the Claim relates (with the approval of at least
seventy-five percent (75%) of the Note Investors), if the Investors are entitled
to indemnification hereunder, or the Company, if the Company is entitled to
indemnification hereunder, as applicable. The failure to deliver written notice
to the indemnifying party within a reasonable time of the commencement of any
such action shall not relieve such indemnifying party of any liability to the
Indemnified Person or Indemnified Party under this Section 6, except to the
extent that the indemnifying party is actually prejudiced in its ability to
defend such action. The indemnification required by this Section 6 shall be made
by periodic payments of the amount thereof during the course of the
investigation or defense, as such expense, loss, damage or liability is incurred
and is due and payable.

     7.   CONTRIBUTION. To the extent any indemnification by an indemnifying
party is prohibited or limited by law, the indemnifying party agrees to make the
maximum contribution with respect to any amounts for which it would otherwise be
liable under Section 6 to the fullest


<PAGE>

extent permitted by law; PROVIDED, HOWEVER, that (i) no contribution shall be
made under circumstances where the maker would not have been liable for
indemnification under the fault standards set forth in Section 6, (ii) no seller
of Registrable Securities guilty of fraudulent misrepresentation (within the
meaning of Section 11(f) of the 1933 Act) shall be entitled to contribution from
any seller of Registrable Securities who was not guilty of such fraudulent
misrepresentation, and (iii) contribution (together with any indemnification or
other obligations under this Agreement) by any seller of Registrable Securities
shall be limited in amount to the net amount of proceeds received by such seller
from the sale of such Registrable Securities.

     8.   REPORTS UNDER THE 1934 ACT. With a view to making available to the
Investors the benefits of Rule 144 promulgated under the 1933 Act or any other
similar rule or regulation of the SEC that may at any time permit the investors
to sell Registrable Securities to the public without registration ("RULE 144"),
the Company agrees to:

          a.   make and keep public information available, as those terms are
understood and defined in Rule 144;

          b.   file with the SEC in a timely manner all reports and other
documents required of the Company under the 1933 Act and the 1934 Act so long as
the Company remains subject to such requirements (it being understood that
nothing herein shall limit the Company's obligations under Section 4(c) of the
Securities Purchase Agreement) and the filing of such reports and other
documents is required for the applicable provisions of Rule 144; and

          c.   furnish to each Investor so long as such Investor owns
Registrable Securities, promptly upon request, (i) a written statement by the
Company that it has complied with the reporting requirements of Rule 144, the
1933 Act and the 1934 Act, (ii) a copy of the most recent annual or quarterly
report of the Company and such other reports and documents so filed by the
Company, and (iii) such other information as may be reasonably requested to
permit the Investors to sell such securities pursuant to Rule 144 without
registration.

     9.   ASSIGNMENT OF REGISTRATION RIGHTS. The rights under this Agreement
shall be automatically assignable by the Investors to any transferee of
Registrable Securities having a value of at least $50,000 if: (i) the Investor
agrees in writing with the transferee or assignee to assign such rights, and a
copy of such agreement is furnished to the Company within a reasonable time
after such assignment, (ii) the Company is, within a reasonable time after such
transfer or assignment, furnished with written notice of (a) the name and
address of such transferee or assignee and the circumstances in which such
Registrable Securities are being transferred, and (b) the securities with
respect to which such registration rights are being transferred or assigned,
(iii) following such transfer or assignment, the further disposition of such
securities by the transferee or assignee is restricted under the 1933 Act and
applicable state securities laws, (iv) at or before the time the Company
receives the written notice contemplated by clause (ii) of this sentence, the
transferee or assignee agrees in writing with the Company to be bound by all of
the provisions contained herein, (v) such transfer shall have been made in
accordance with the applicable requirements of the Securities Purchase Agreement
and

<PAGE>

applicable securities laws, and (vi) such transferee shall be an "ACCREDITED
INVESTOR" as that term defined in Rule 501 of Regulation D promulgated under the
1933 Act.

     10.  AMENDMENT OF REGISTRATION RIGHTS. Provisions of this Agreement may be
amended and the observance thereof may be waived (either generally or in a
particular instance and either retroactively or prospectively), only with
written consent of the Company, each of the Note Investors (to the extent such
Note Investor still owns Registrable Securities) and Investors who hold at least
seventy-five percent (75%) of the Registrable Securities. Any amendment or
waiver effected in accordance with this Section 10 shall be binding upon each
Investor and the Company.

     11.  MISCELLANEOUS.

          a.   A person or entity is deemed to be a holder of Registrable
Securities whenever such person or entity owns of record such Registrable
Securities. If the Company receives conflicting instructions, notices or
elections from two or more persons or entities with respect to the same
Registrable Securities, the Company shall act upon the basis of instructions,
notice or election received from the registered owner of such Registrable
Securities.

          b.   Any notices required or permitted to be given under the terms
hereof shall be sent by certified or registered mail (return receipt requested)
or delivered personally or by courier (including a recognized overnight delivery
service) or by facsimile and shall be effective five days after being placed in
the mail, if mailed by regular United States mail, or upon receipt, if delivered
personally or by courier (including a recognized overnight delivery service) or
by facsimile, in each case addressed to a party. The addresses for such
communications shall be:

                            If to the Company:

                            Cytomedix, Inc.
                            Three Parkway North
                            Deerfield, Illinois 60015
                            Attention:  President and Chief Executive Officer
                            Telephone:     847-405-7800
                            Facsimile:     847-405-7801

If to an Investor: to the address set forth immediately below such Investor's
name on the signature pages to the Securities Purchase Agreement.

          c.   Failure of any party to exercise any right or remedy under this
Agreement or otherwise, or delay by a party in exercising such right or remedy,
shall not operate as a waiver thereof.

          d.   THIS AGREEMENT SHALL BE ENFORCED, GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF ILLINOIS APPLICABLE TO AGREEMENTS MADE
AND TO BE PERFORMED ENTIRELY WITHIN

<PAGE>

SUCH STATE, WITHOUT REGARD TO THE PRINCIPLES OF CONFLICT OF LAWS. THE PARTIES
HERETO HEREBY SUBMIT TO THE EXCLUSIVE JURISDICTION OF THE UNITED STATES FEDERAL
COURTS LOCATED IN CHICAGO, ILLINOIS WITH RESPECT TO ANY DISPUTE ARISING UNDER
THIS AGREEMENT, THE AGREEMENTS ENTERED INTO IN CONNECTION HEREWITH OR THE
TRANSACTIONS CONTEMPLATED HEREBY OR THEREBY. BOTH PARTIES IRREVOCABLY WAIVE THE
DEFENSE OF AN INCONVENIENT FORUM TO THE MAINTENANCE OF SUCH SUIT OR PROCEEDING.
BOTH PARTIES FURTHER AGREE THAT SERVICE OF PROCESS UPON A PARTY MAILED BY FIRST
CLASS MAIL SHALL BE DEEMED IN EVERY RESPECT EFFECTIVE SERVICE OF PROCESS UPON
THE PARTY IN ANY SUCH SUIT OR PROCEEDING. NOTHING HEREIN SHALL AFFECT ANY
PARTY'S RIGHT TO SERVE PROCESS IN ANY OTHER MANNER PERMITTED BY LAW. ALL PARTIES
AGREE THAT A FINAL NON-APPEALABLE JUDGMENT IN ANY SUCH SUIT OR PROCEEDING SHALL
BE CONCLUSIVE AND MAY BE ENFORCED IN OTHER JURISDICTIONS BY SUIT ON SUCH
JUDGMENT OR IN ANY OTHER LAWFUL MANNER. THE PARTY WHICH DOES NOT PREVAIL IN ANY
DISPUTE ARISING UNDER THIS AGREEMENT SHALL BE RESPONSIBLE FOR ALL FEES AND
EXPENSES, INCLUDING ATTORNEYS' FEES, INCURRED BY THE PREVAILING PARTY IN
CONNECTION WITH SUCH DISPUTE.

          e.   In the event that any provision of this Agreement is invalid or
unenforceable under any applicable statute or rule of law, then such provision
shall be deemed inoperative to the extent that it may conflict therewith and
shall be deemed modified to conform with such statute or rule of law. Any
provision hereof which may prove invalid or unenforceable under any law shall
not affect the validity or enforceability of any other provision hereof.

          f.   This Agreement, the Securities Purchase Agreement (including all
schedules and exhibits thereto) and the Loan Documents (as defined in the Notes)
constitute the entire agreement among the parties hereto with respect to the
subject matter hereof and thereof. There are no restrictions, promises,
warranties or undertakings, other than those set forth or referred to herein and
therein. This Agreement and the Securities Purchase Agreement supersede all
prior agreements and understandings among the parties hereto with respect to the
subject matter hereof and thereof.

          g.   Subject to the requirements of Section 9 hereof, this Agreement
shall be binding upon and inure to the benefit of the parties and their
successors and assigns.

          h.   The headings in this Agreement are for convenience of reference
only and shall not form part of, or affect the interpretation of, this
Agreement.

          i.   This Agreement may be executed in two or more counterparts, each
of which shall be deemed an original but all of which shall constitute one and
the same agreement and shall become effective when counterparts have been signed
by each party and delivered to the other party. This Agreement, once executed by
a party, may be delivered to the other party


<PAGE>

hereto by facsimile transmission of a copy of this Agreement bearing the
signature of the party so delivering this Agreement.

          j.   Each party shall do and perform, or cause to be done and
performed, all such further acts and things, and shall execute and deliver all
such other agreements, certificates, instruments and documents, as the other
party may reasonably request in order to carry out the intent and accomplish the
purposes of this Agreement and the consummation of the transactions contemplated
hereby.

          k.   Except as otherwise provided herein, all consents and other
determinations to be made by the Investors pursuant to this Agreement shall be
made by Investors at least seventy-five percent (75%) of the Registrable
Securities, determined as if all of the Notes then outstanding have been
converted into Registrable Securities.

          l.   The Company acknowledges that a breach by it of its obligations
hereunder will cause irreparable harm to each Investor by vitiating the intent
and purpose of the transactions contemplated hereby. Accordingly, the Company
acknowledges that the remedy at law for breach of its obligations under this
Agreement will be inadequate and agrees, in the event of a breach or threatened
breach by the Company of any of the provisions under this Agreement, that each
Investor shall be entitled, in addition to all other available remedies in law
or in equity, and in addition to the penalties assessable herein, to an
injunction or injunctions restraining, preventing or curing any breach of this
Agreement and to enforce specifically the terms and provisions hereof, without
the necessity of showing economic loss and without any bond or other security
being required.

          m.   The language used in this Agreement will be deemed to be the
language chosen by the parties to express their mutual intent, and no rules of
strict construction will be applied against any party.

     IN WITNESS WHEREOF, the Company has caused this Agreement to be duly
executed for the benefit of the Note Investors as of the date first above
written.

                                 CYTOMEDIX, INC.

                                  By: /s/ JAMES A. COUR
                                      ------------------------------------

                                  Title: Chief Executive Officer
                                         ------------------------------------


<PAGE>

                                   EXHIBIT "A"

                    List of Note Investors and Beneficiaries

<TABLE>
<CAPTION>
NAME                                                   PRINCIPAL AMOUNT OF NOTES
----                                                   -------------------------
<S>                                                    <C>


</TABLE>