<PAGE>   1
     As filed with the Securities and Exchange Commission on July 10, 1997

                                                         REGISTRATION NO. 33 -

================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                             ----------------------

                                    FORM S-8
                             REGISTRATION STATEMENT
                                    UNDER THE
                             SECURITIES ACT OF 1933

                             ----------------------

                                  PROTEON, INC.
             (Exact name of Registrant as specified in its charter)

                 MASSACHUSETTS                         04-2531856
          (State or other jurisdiction              (I.R.S. Employer
        of incorporation or organization)          Identification No.)
                 
 
                              NINE TECHNOLOGY DRIVE
                        WESTBOROUGH, MASSACHUSETTS 01581
                                 (508) 898-2800
                    (Address of Principal Executive Offices)

                  PROTEON, INC. 1991 RESTATED STOCK OPTION PLAN
                   PROTEON, INC. EMPLOYEE STOCK PURCHASE PLAN
                            (Full title of the plans)

                        DANIEL J. CAPONE, JR., PRESIDENT
                                  PROTEON, INC.
                              NINE TECHNOLOGY DRIVE
                        WESTBOROUGH, MASSACHUSETTS 01581
                                 (508) 898-2800
    (Name, address, including zip code, and telephone number, including area
                           code, of agent for service)

                             ----------------------

<TABLE>
                         CALCULATION OF REGISTRATION FEE
<CAPTION>
================================================================================================
                                             Proposed           Proposed
      Title of                               maximum            maximum
  securities to be      Amount to be      offering price       aggregate          Amount of
     registered         registered(1)      per share(2)    offering price(2)  registration fee
================================================================================================
<S>                         <C>              <C>             <C>                  <C>     
 Common Stock, $.01         800,000          $1.78           $1,424,000           $431.47
      par value
================================================================================================
</TABLE>

(1)  The number of shares of common stock, par value $.01 per share ("Common
     Stock"), stated above consists of the aggregate number of additional shares
     not previously registered which may be sold upon the exercise of options
     which have been granted and/or may hereafter be granted under the Proteon,
     Inc. 1991 Restated Stock Option Plan (the "1991 Option Plan") and which may
     be sold pursuant to the Proteon, Inc. Employee Stock Purchase Plan (the
     "Purchase Plan"). The 1991 Option Plan and the Purchase Plan are
     collectively referred to as the "Plans". The maximum number of shares which
     may be sold under the Plans is subject to adjustment in accordance with
     certain anti-dilution and other provisions of said Plans. Accordingly,
     pursuant to Rule 416 under the Securities Act of 1933, as amended (the
     "Securities Act"), this Registration Statement covers, in addition to the
     number of shares stated above, an indeterminate number of shares which may
     be subject to grant or otherwise issuable after the operation of any such
     anti-dilution and other provisions.

(2)  This calculation is made solely for the purpose of determining the
     registration fee pursuant to the provisions of Rule 457(h) under the
     Securities Act as follows: Since no additional options have been granted
     under the Plans, the fee is calculated on the basis of the average of the
     high and low sale prices per share of the Common Stock on The Nasdaq Stock
     Market ("Nasdaq") as of a date (July 7, 1997) within 5 business days prior
     to filing this Registration Statement.

================================================================================


<PAGE>   2
                                EXPLANATORY NOTE


     This Registration Statement relates to the registration of 500,000
additional shares of Common Stock authorized for issuance under the 1991 Option
Plan and 300,000 additional shares of Common Stock for issuance under the
Purchase Plan. In accordance with the instructional Note to Part I of Form S-8
as promulgated by the Securities and Exchange Commission, the information
specified by Part I of Form S-8 has been omitted from this Registration
Statement on Form S-8 for offers of Common Stock pursuant to the Plans.




<PAGE>   3
                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT


Item 3.  Incorporation of Certain Documents by Reference.
---------------------------------------------------------

     The following documents filed by the Registrant with the Commission are
incorporated herein by reference:

     (a) The Company's Annual Report on Form 10-K for the fiscal year ended
December 31, 1996.

     (b) The Company's Quarterly Report on Form 10-Q for the quarter ended March
31, 1997.

     (c) The description of the Common Stock contained in the Registrant's
Registration Statement on Form 8-A (File No. 0-19175), filed under the
Securities Exchange Act of 1934, including any amendment or report filed for the
purpose of updating such description.

     All reports and other documents filed by the Registrant after the date
hereof pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Securities
Exchange Act of 1934 prior to the filing of a post-effective amendment which
indicates that all securities offered hereby have been sold or which deregisters
all securities then remaining unsold, shall be deemed to be incorporated by
reference herein and to be part hereof from the date of filing of such reports
and documents.

Item 4.  Description of Securities.
-----------------------------------

     Not applicable.

Item 5.  Interests of Named Experts and Counsel.
------------------------------------------------

      Not applicable.

Item 6.  Indemnification of Directors and Officers.
---------------------------------------------------

     Incorporated herein by reference from Registration Statement on Form S-1,
No. 33-40073.

Item 7.  Exemption from Registration Claimed.
---------------------------------------------

                                      II-1

<PAGE>   4

     Not applicable.

Item 8.  Exhibits.
------------------

       (4.1)  Article 4 of Restated Articles of Organization, as Amended (Filed
              as Exhibit 4.1 to the Registrant's Annual Report on Form 10-K for
              the fiscal year ended December 31, 1991, and incorporated herein
              by reference).

       (4.2)  By-Laws, as amended and restated (Filed as Exhibit 3.3 to the
              Registrant's Annual Report on Form 10-K for the fiscal year ended
              December 31, 1992, and incorporated herein by reference).

       (4.3)  Form of Common Stock Certificate (Filed as Exhibit 4.2 to the
              Registrant's Quarterly Report on Form 10-Q for the fiscal quarter
              ended June 29, 1996, and incorporated herein by reference).

       (5)    Opinion of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. as
              to the legality of shares being registered.

       (23.1) Consent of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.
              (included in opinion of counsel filed as Exhibit 5).

       (23.2) Consent of Coopers & Lybrand L.L.P.

       (24)   Power of Attorney to file future amendments (set forth on the
              signature page of this Registration Statement).

       (99.1) Proteon, Inc. 1991 Restated Stock Option Plan (filed as Exhibit
              10.6 to the Registration Statement on Form S-1, Registration No.
              33-40073, as amended, and incorporated herein by reference).

       (99.2) Proteon, Inc. Employee Stock Purchase Plan, as amended (filed as
              Exhibit 28.1 to the Registration Statement on Form S-8,
              Registration No. 33-41702, and incorporated herein by reference).


Item 9.  Undertakings.
----------------------

(a)  The undersigned Registrant hereby undertakes:

     (1) To file, during any period in which offers or sales are being made, a
     post-effective amendment to this Registration Statement:

                                      II-2


<PAGE>   5

     (i) To include any prospectus required by Section 10(a)(3) of the
     Securities Act of 1933;

     (ii) To reflect in the prospectus any facts or events arising after the
     effective date of the Registration Statement (or the most recent
     post-effective amendment thereof) which, individually or in the aggregate,
     represents a fundamental change in the information set forth in the
     Registration Statement. Notwithstanding the foregoing, any increase or
     decrease in volume of securities offered (if the total dollar value of
     securities offered would not exceed that which was registered) and any
     deviation from the low or high end of the estimated maximum offering range
     may be reflected in the form of prospectus filed with the Commission
     pursuant to Rule 424(b) (Section 230.424(b) of this chapter) if, in the
     aggregate, the changes in volume and price represent no more than a 20%
     change in the maximum aggregate offering price set forth in the
     "Calculation of Registration Fee" table in the effective Registration
     Statement.

     (iii) To include any material information with respect to the plan of
     distribution not previously disclosed in the Registration Statement or any
     material change to such information in the Registration Statement;

          PROVIDED, HOWEVER, that paragraphs (a)(1)(i) and (a)(1)(ii) do not
     apply if the Registration Statement is on Form S-3 or Form S-8, and the
     information required to be included in a post-effective amendment by those
     paragraphs is contained in periodic reports filed by the Registrant
     pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of
     1934 that are incorporated by reference in this Registration Statement.

     (2) That, for the purpose of determining any liability under the Securities
     Act of 1933, each such post-effective amendment shall be deemed to be a new
     registration statement relating to the securities offered therein, and the
     offering of such securities at that time shall be deemed to be the initial
     bona fide offering thereof.

     (3) To remove from registration by means of a post-effective amendment any
     of the securities being registered which remain unsold at the termination
     of the offering.

(b)  The undersigned Registrant hereby undertakes that, for purposes of
     determining any liability under the Securities Act of 1933, each filing of
     the Registrant's annual report pursuant to Section 13(a) or Section 15(d)
     of the Securities Exchange Act of 1934 that is incorporated by reference in
     this Registration Statement shall be deemed to be a new registration
     statement relating to the securities offered therein, and the offering of
     such securities at that time shall be deemed to be the initial bona fide
     offering thereof.

(c)  Insofar as indemnification for liabilities arising under the Securities Act
     of 1933 may be permitted to directors, officers and controlling persons of
     the Registrant pursuant to the foregoing provisions, or otherwise, the
     Registrant has been advised that in the opinion of the Securities and
     Exchange Commission such indemnification is against public policy as


                                      II-3
<PAGE>   6

     expressed in the Act and is, therefore, unenforceable. In the event that a
     claim for indemnification against such liabilities (other than the payment
     by the Registrant of expenses incurred or paid by a director, officer or
     controlling person of the Registrant in the successful defense of any
     action, suit or proceeding) is asserted by such director, officer or
     controlling person in connection with the securities being registered, the
     Registrant will, unless in the opinion of its counsel the matter has been
     settled by controlling precedent, submit to a court of appropriate
     jurisdiction the question whether such indemnification by it is against
     public policy as expressed in the Act and will be governed by the final
     adjudication of such issue.

                                      II-4

<PAGE>   7



                                   SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, the Registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in Westborough, MA, on July 7, 1997.

                                    PROTEON, INC.



                                    By: /S/ Steven T. Shedd
                                        ----------------------------------------
                                        Steven T. Shedd
                                        Chief Financial Officer



     Each person whose signature appears below constitutes and appoints Steven
T. Shedd his true and lawful attorney-in-fact and agent, with full power
of substitution and resubstitution, for him and in his name, place and stead,
and in any and all capacities, to sign any and all amendments (including
post-effective amendments) to this Registration Statement on Form S-8 of
Proteon, Inc. and to file the same, with all exhibits thereto and other
documents in connection therewith, with the Securities and Exchange Commission,
granting unto said attorney-in-fact and agent, full power and authority to do
and perform each and every act and thing requisite or necessary to be done in or
about the premises, as full to all intents and purposes as he might or could do
in person, hereby ratifying and confirming all that said attorney-in-fact and
agents or any of them or their or his substitute or substitutes may lawfully do
or cause to be done by virtue hereof.

     Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the dates indicated.

<TABLE>
<CAPTION>
        Signature                                Title                             Date            
        ---------                                -----                             ----            

<S>                             <C>                                            <C>  
By: /s/ Daniel J. Capone, Jr.   Director, President, Chief Executive Officer   July 7, 1997
------------------------------  (principal executive officer)                
Daniel J. Capone, Jr.           

                                
By: /s/ Steven T. Shedd         Chief Financial Officer                        July 7, 1997
------------------------------  (principal financial officer)
Steven T. Shedd   


By: /s/ David Clark             Director                                       July 7, 1997
------------------------------
David Clark

</TABLE>


                                      II-5
<PAGE>   8
<TABLE>

<S>                             <C>                                            <C>  
By: /s/ Robert M. Glorioso      Director                                       July 7, 1997
------------------------------
Robert M. Glorioso


By:                             Director (Chairman)                            July _, 1997
------------------------------
Howard C. Salwen
</TABLE>

                                      II-6

<PAGE>   9



                                PROTEON, INC.

                         INDEX TO EXHIBITS FILED WITH
                       FORM S-8 REGISTRATION STATEMENT


Exhibit
Number    Description
------    -----------

4.1       Article 4 of Restated Articles of Organization, as Amended (Filed as
          Exhibit 4.1 to the Registrant's Annual Report on Form 10-K for the
          fiscal year ended December 31, 1991, and incorporated herein by
          reference).

4.2       By-Laws, as amended and restated (Filed as Exhibit 3.3 to the
          Registrant's Annual Report on Form 10-K for the fiscal year ended
          December 31, 1992, and incorporated herein by reference).

4.3       Form of Common Stock Certificate (Filed as Exhibit 4.2 to the
          Registrant's Quarterly Report on Form 10-Q for the fiscal quarter 
          ended June 29, 1996, and incorporated herein by reference).

5         Opinion of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. as to
          the legality of shares being registered.

23.1      Consent of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo,
          P.C.(included in opinion of counsel filed as Exhibit 5).

23.2      Consent of Coopers & Lybrand L.L.P.

24        Power of Attorney to file future amendments (set forth on the
          signature page of this Registration Statement).

99.1      Proteon, Inc. 1991 Restated Stock Option Plan (filed as Exhibit 10.6
          to the Registration Statement on Form S-1, Registration No. 33-40073,
          as amended, and incorporated herein by reference).

99.2      Proteon, Inc. Employee Stock Purchase Plan, as amended (filed as
          Exhibit 28.1 to the Registration Statement on Form S-8, Registration
          No. 33-41702, and incorporated herein by reference).


                                      II-7
[{"type": "S-8", "sequence": "1", "description": "PROTEON, INC.", "secsgml_size_bytes": 18204}]
{"company-data": {"conformed-name": "PROTEON INC/MA", "cik": "0000874316", "assigned-sic": "3576", "irs-number": "042531856", "state-of-incorporation": "MA", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-31055", "film-number": "97639130"}, "business-address": {"street1": "NINE TECHNOLOGY DRIVE", "city": "WESTBOROUGH", "state": "MA", "zip": "01581", "phone": "5088982800"}, "mail-address": {"street1": "9 TECHNOLOGY DR", "city": "WESTBOROUGH", "state": "MA", "zip": "01581"}}
1
     As filed with the Securities and Exchange Commission on July 10, 1997

                                                         REGISTRATION NO. 33 -

================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                             ----------------------

                                    FORM S-8
                             REGISTRATION STATEMENT
                                    UNDER THE
                             SECURITIES ACT OF 1933

                             ----------------------

                                  PROTEON, INC.
             (Exact name of Registrant as specified in its charter)

                 MASSACHUSETTS                         04-2531856
          (State or other jurisdiction              (I.R.S. Employer
        of incorporation or organization)          Identification No.)
                 
 
                              NINE TECHNOLOGY DRIVE
                        WESTBOROUGH, MASSACHUSETTS 01581
                                 (508) 898-2800
                    (Address of Principal Executive Offices)

                  PROTEON, INC. 1991 RESTATED STOCK OPTION PLAN
                   PROTEON, INC. EMPLOYEE STOCK PURCHASE PLAN
                            (Full title of the plans)

                        DANIEL J. CAPONE, JR., PRESIDENT
                                  PROTEON, INC.
                              NINE TECHNOLOGY DRIVE
                        WESTBOROUGH, MASSACHUSETTS 01581
                                 (508) 898-2800
    (Name, address, including zip code, and telephone number, including area
                           code, of agent for service)

                             ----------------------

                         CALCULATION OF REGISTRATION FEE
================================================================================================
                                             Proposed           Proposed
      Title of                               maximum            maximum
  securities to be      Amount to be      offering price       aggregate          Amount of
     registered         registered(1)      per share(2)    offering price(2)  registration fee
================================================================================================
Common Stock, $.01         800,000          $1.78           $1,424,000           $431.47
      par value
================================================================================================
(1)  The number of shares of common stock, par value $.01 per share ("Common
     Stock"), stated above consists of the aggregate number of additional shares
     not previously registered which may be sold upon the exercise of options
     which have been granted and/or may hereafter be granted under the Proteon,
     Inc. 1991 Restated Stock Option Plan (the "1991 Option Plan") and which may
     be sold pursuant to the Proteon, Inc. Employee Stock Purchase Plan (the
     "Purchase Plan"). The 1991 Option Plan and the Purchase Plan are
     collectively referred to as the "Plans". The maximum number of shares which
     may be sold under the Plans is subject to adjustment in accordance with
     certain anti-dilution and other provisions of said Plans. Accordingly,
     pursuant to Rule 416 under the Securities Act of 1933, as amended (the
     "Securities Act"), this Registration Statement covers, in addition to the
     number of shares stated above, an indeterminate number of shares which may
     be subject to grant or otherwise issuable after the operation of any such
     anti-dilution and other provisions.

(2)  This calculation is made solely for the purpose of determining the
     registration fee pursuant to the provisions of Rule 457(h) under the
     Securities Act as follows: Since no additional options have been granted
     under the Plans, the fee is calculated on the basis of the average of the
     high and low sale prices per share of the Common Stock on The Nasdaq Stock
     Market ("Nasdaq") as of a date (July 7, 1997) within 5 business days prior
     to filing this Registration Statement.

================================================================================
2
                                EXPLANATORY NOTE

     This Registration Statement relates to the registration of 500,000
additional shares of Common Stock authorized for issuance under the 1991 Option
Plan and 300,000 additional shares of Common Stock for issuance under the
Purchase Plan. In accordance with the instructional Note to Part I of Form S-8
as promulgated by the Securities and Exchange Commission, the information
specified by Part I of Form S-8 has been omitted from this Registration
Statement on Form S-8 for offers of Common Stock pursuant to the Plans.
3
                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  Incorporation of Certain Documents by Reference.
---------------------------------------------------------

     The following documents filed by the Registrant with the Commission are
incorporated herein by reference:

     (a) The Company's Annual Report on Form 10-K for the fiscal year ended
December 31, 1996.

     (b) The Company's Quarterly Report on Form 10-Q for the quarter ended March
31, 1997.

     (c) The description of the Common Stock contained in the Registrant's
Registration Statement on Form 8-A (File No. 0-19175), filed under the
Securities Exchange Act of 1934, including any amendment or report filed for the
purpose of updating such description.

     All reports and other documents filed by the Registrant after the date
hereof pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Securities
Exchange Act of 1934 prior to the filing of a post-effective amendment which
indicates that all securities offered hereby have been sold or which deregisters
all securities then remaining unsold, shall be deemed to be incorporated by
reference herein and to be part hereof from the date of filing of such reports
and documents.

Item 4.  Description of Securities.
-----------------------------------

     Not applicable.

Item 5.  Interests of Named Experts and Counsel.
------------------------------------------------

      Not applicable.

Item 6.  Indemnification of Directors and Officers.
---------------------------------------------------

     Incorporated herein by reference from Registration Statement on Form S-1,
No. 33-40073.

Item 7.  Exemption from Registration Claimed.
---------------------------------------------

                                      II-1
4

     Not applicable.

Item 8.  Exhibits.
------------------

       (4.1)  Article 4 of Restated Articles of Organization, as Amended (Filed
              as Exhibit 4.1 to the Registrant's Annual Report on Form 10-K for
              the fiscal year ended December 31, 1991, and incorporated herein
              by reference).

       (4.2)  By-Laws, as amended and restated (Filed as Exhibit 3.3 to the
              Registrant's Annual Report on Form 10-K for the fiscal year ended
              December 31, 1992, and incorporated herein by reference).

       (4.3)  Form of Common Stock Certificate (Filed as Exhibit 4.2 to the
              Registrant's Quarterly Report on Form 10-Q for the fiscal quarter
              ended June 29, 1996, and incorporated herein by reference).

       (5)    Opinion of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. as
              to the legality of shares being registered.

       (23.1) Consent of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.
              (included in opinion of counsel filed as Exhibit 5).

       (23.2) Consent of Coopers & Lybrand L.L.P.

       (24)   Power of Attorney to file future amendments (set forth on the
              signature page of this Registration Statement).

       (99.1) Proteon, Inc. 1991 Restated Stock Option Plan (filed as Exhibit
              10.6 to the Registration Statement on Form S-1, Registration No.
              33-40073, as amended, and incorporated herein by reference).

       (99.2) Proteon, Inc. Employee Stock Purchase Plan, as amended (filed as
              Exhibit 28.1 to the Registration Statement on Form S-8,
              Registration No. 33-41702, and incorporated herein by reference).

Item 9.  Undertakings.
----------------------

(a)  The undersigned Registrant hereby undertakes:

     (1) To file, during any period in which offers or sales are being made, a
     post-effective amendment to this Registration Statement:

                                      II-2
5

     (i) To include any prospectus required by Section 10(a)(3) of the
     Securities Act of 1933;

     (ii) To reflect in the prospectus any facts or events arising after the
     effective date of the Registration Statement (or the most recent
     post-effective amendment thereof) which, individually or in the aggregate,
     represents a fundamental change in the information set forth in the
     Registration Statement. Notwithstanding the foregoing, any increase or
     decrease in volume of securities offered (if the total dollar value of
     securities offered would not exceed that which was registered) and any
     deviation from the low or high end of the estimated maximum offering range
     may be reflected in the form of prospectus filed with the Commission
     pursuant to Rule 424(b) (Section 230.424(b) of this chapter) if, in the
     aggregate, the changes in volume and price represent no more than a 20%
     change in the maximum aggregate offering price set forth in the
     "Calculation of Registration Fee" table in the effective Registration
     Statement.

     (iii) To include any material information with respect to the plan of
     distribution not previously disclosed in the Registration Statement or any
     material change to such information in the Registration Statement;

          PROVIDED, HOWEVER, that paragraphs (a)(1)(i) and (a)(1)(ii) do not
     apply if the Registration Statement is on Form S-3 or Form S-8, and the
     information required to be included in a post-effective amendment by those
     paragraphs is contained in periodic reports filed by the Registrant
     pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of
     1934 that are incorporated by reference in this Registration Statement.

     (2) That, for the purpose of determining any liability under the Securities
     Act of 1933, each such post-effective amendment shall be deemed to be a new
     registration statement relating to the securities offered therein, and the
     offering of such securities at that time shall be deemed to be the initial
     bona fide offering thereof.

     (3) To remove from registration by means of a post-effective amendment any
     of the securities being registered which remain unsold at the termination
     of the offering.

(b)  The undersigned Registrant hereby undertakes that, for purposes of
     determining any liability under the Securities Act of 1933, each filing of
     the Registrant's annual report pursuant to Section 13(a) or Section 15(d)
     of the Securities Exchange Act of 1934 that is incorporated by reference in
     this Registration Statement shall be deemed to be a new registration
     statement relating to the securities offered therein, and the offering of
     such securities at that time shall be deemed to be the initial bona fide
     offering thereof.

(c)  Insofar as indemnification for liabilities arising under the Securities Act
     of 1933 may be permitted to directors, officers and controlling persons of
     the Registrant pursuant to the foregoing provisions, or otherwise, the
     Registrant has been advised that in the opinion of the Securities and
     Exchange Commission such indemnification is against public policy as

                                      II-3
6

     expressed in the Act and is, therefore, unenforceable. In the event that a
     claim for indemnification against such liabilities (other than the payment
     by the Registrant of expenses incurred or paid by a director, officer or
     controlling person of the Registrant in the successful defense of any
     action, suit or proceeding) is asserted by such director, officer or
     controlling person in connection with the securities being registered, the
     Registrant will, unless in the opinion of its counsel the matter has been
     settled by controlling precedent, submit to a court of appropriate
     jurisdiction the question whether such indemnification by it is against
     public policy as expressed in the Act and will be governed by the final
     adjudication of such issue.

                                      II-4
7

                                   SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, the Registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in Westborough, MA, on July 7, 1997.

                                    PROTEON, INC.

                                    By: /S/ Steven T. Shedd
                                        ----------------------------------------
                                        Steven T. Shedd
                                        Chief Financial Officer

     Each person whose signature appears below constitutes and appoints Steven
T. Shedd his true and lawful attorney-in-fact and agent, with full power
of substitution and resubstitution, for him and in his name, place and stead,
and in any and all capacities, to sign any and all amendments (including
post-effective amendments) to this Registration Statement on Form S-8 of
Proteon, Inc. and to file the same, with all exhibits thereto and other
documents in connection therewith, with the Securities and Exchange Commission,
granting unto said attorney-in-fact and agent, full power and authority to do
and perform each and every act and thing requisite or necessary to be done in or
about the premises, as full to all intents and purposes as he might or could do
in person, hereby ratifying and confirming all that said attorney-in-fact and
agents or any of them or their or his substitute or substitutes may lawfully do
or cause to be done by virtue hereof.

     Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities and on the dates indicated.
Signature                                Title                             Date            
        ---------                                -----                             ----
By: /s/ Daniel J. Capone, Jr.   Director, President, Chief Executive Officer   July 7, 1997
------------------------------  (principal executive officer)                
Daniel J. Capone, Jr.           

                                
By: /s/ Steven T. Shedd         Chief Financial Officer                        July 7, 1997
------------------------------  (principal financial officer)
Steven T. Shedd   

By: /s/ David Clark             Director                                       July 7, 1997
------------------------------
David Clark
II-5
8
By: /s/ Robert M. Glorioso      Director                                       July 7, 1997
------------------------------
Robert M. Glorioso

By:                             Director (Chairman)                            July _, 1997
------------------------------
Howard C. Salwen
II-6
9

                                PROTEON, INC.

                         INDEX TO EXHIBITS FILED WITH
                       FORM S-8 REGISTRATION STATEMENT

Exhibit
Number    Description
------    -----------

4.1       Article 4 of Restated Articles of Organization, as Amended (Filed as
          Exhibit 4.1 to the Registrant's Annual Report on Form 10-K for the
          fiscal year ended December 31, 1991, and incorporated herein by
          reference).

4.2       By-Laws, as amended and restated (Filed as Exhibit 3.3 to the
          Registrant's Annual Report on Form 10-K for the fiscal year ended
          December 31, 1992, and incorporated herein by reference).

4.3       Form of Common Stock Certificate (Filed as Exhibit 4.2 to the
          Registrant's Quarterly Report on Form 10-Q for the fiscal quarter 
          ended June 29, 1996, and incorporated herein by reference).

5         Opinion of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. as to
          the legality of shares being registered.

23.1      Consent of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo,
          P.C.(included in opinion of counsel filed as Exhibit 5).

23.2      Consent of Coopers & Lybrand L.L.P.

24        Power of Attorney to file future amendments (set forth on the
          signature page of this Registration Statement).

99.1      Proteon, Inc. 1991 Restated Stock Option Plan (filed as Exhibit 10.6
          to the Registration Statement on Form S-1, Registration No. 33-40073,
          as amended, and incorporated herein by reference).

99.2      Proteon, Inc. Employee Stock Purchase Plan, as amended (filed as
          Exhibit 28.1 to the Registration Statement on Form S-8, Registration
          No. 33-41702, and incorporated herein by reference).

                                      II-7