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would contain material information not contained herein and to which prospective
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shall be deemed superseded and replaced in its entirety by such offering
circular or memorandum. No representation or warranty can be given with respect
to the accuracy or completeness of the information herein, or that any future
offer of securities or transactions would conform to the terms hereof. Morgan
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The following information may contain general, summary discussions of certain
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The projections or other estimates in these materials (if any), including
estimates of returns or performance, are forward-looking statements based upon
certain assumptions and are preliminary in nature. Actual results are difficult
to predict and may depend upon events outside the issuer's or counterparty's
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and Morgan Stanley does not purport that any such assumptions will reflect
actual future events. Accordingly, there can be no assurance that estimated
returns or projections will be realized or that actual returns or performance
results will not be materially different than those estimated herein. Any such
estimated returns and projections should be viewed as hypothetical. Recipients
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indicative of future results. Price and availability are subject to change
without notice.

Notwithstanding any other express or implied agreement, arrangement, or
understanding to the contrary, Morgan Stanley and each recipient hereof are
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all persons, without limitation of any kind from the commencement of
discussions, the U.S. federal income tax treatment of the transaction ("tax
treatment") and any fact that may be relevant to understanding the tax treatment
of the transaction described herein ("tax structure") and all materials of any
kind (including opinions or other tax analyses) that are provided to such person
relating to such tax treatment and tax structure, except where confidentiality
is reasonably necessary to comply with securities laws (including, where
applicable, confidentiality regarding the identity of an issuer of securities or
its affiliates, agents and advisors).

The offer or sale of securities or transactions may be restricted by law.
Additionally, transfers of any such securities or instruments may be limited by
law or the terms thereof. Unless noted herein, neither Morgan Stanley or any
issuer of securities has taken or will take any action in any jurisdiction that
would permit a public offering of Notes, or possession or distribution of any
offering material in relation thereto, in any country or jurisdiction where
action for such purpose is required. Recipients are required to inform
themselves of and comply with any legal or contractual restrictions on their
purchase, holding, sale, exercise of rights or performance of obligations under
any transaction. Morgan Stanley does not undertake or have any responsibility to
notify you of any changes to the attached information. Morgan Stanley & Co.
Incorporated, its affiliates and others associated with it may have positions
in, and may effect transactions in, securities and instruments of issuers
mentioned herein and may also perform or seek to perform investment banking
services for the issuers of such securities and instruments. Additional
information is available upon request.

With respect to any UK recipients, this communication is directed only to those
persons who are market counterparties or intermediate customers (as defined in
the UK Financial Services Authority's rules).


Asset Backed Certificates
IXIS
2005-HE1

Tranche A-4



-------------------------------------------------------   -----------------------------------------
                 PP75Call     PP100Call     PP125Call        PP75Mat       PP100Mat     PP125Mat
DM / Price
-------------------------------------------------------   -----------------------------------------

           31     100.4216      100.3202      100.2541         101.2061     100.9909      100.8099
           32     100.3371      100.2561      100.2032         101.1015     100.9098      100.7451
           33     100.2527      100.1920      100.1524         100.9971     100.8288      100.6803
           34     100.1684      100.1280      100.1015         100.8927     100.7478      100.6156
           35     100.0842      100.0640      100.0508         100.7885     100.6669      100.5509
           36     100.0000      100.0000      100.0000         100.6845     100.5861      100.4863
           37      99.9159       99.9361       99.9493         100.5805     100.5054      100.4217
           38      99.8319       99.8722       99.8986         100.4767     100.4247      100.3571
           39      99.7480       99.8084       99.8479         100.3730     100.3442      100.2926
           40      99.6641       99.7446       99.7972         100.2695     100.2637      100.2282
           41      99.5804       99.6809       99.7466         100.1661     100.1832      100.1638
-------------------------------------------------------   -----------------------------------------
Average Life          9.53          6.99          5.43            12.25         9.11          7.08
Mod Duration          8.31          6.32          5.01            10.21         7.93          6.35
-------------------------------------------------------   -----------------------------------------