160
`
`lm111111wlogy Toda.Y. uo/. J, No. 6, /fJ,�2
`
`
`
`
`
`The three-dimensional structure of antibodies
`
`Markus Marquart and Johann Deisenhof er
`
`
`IL D-8033 Marrinsried,
`f.R.G.
`Max-Planck lnsritul fi.ir Biochemie, Abtcilung Strukrurforschung
`
`Antibody molecules are glycoproteins which occur in
`vertebrate species. They recognize and bind an enor­
`mous variety of foreign substances (antigens) and sub­
`sequently trigger further defense mechanisms at the
`molecular or cellular
`level. Specific recognition
`requires surface structures complementary to the
`antigen and hence a huge v;:iriety of antibody
`molecules. In contrast the effector functions need
`identical interaction sites in all antibody molecules.
`The determination of the primary structure of
`imrnunoglobulins1-3 and the X-ray crystallographic
`studies of several antibody molecules and
`frag­
`ments•.s.7.rn.iz-rs led to an advanced understanding of
`the way in which antibodies meet these opposing
`requirements.
`
`I is a schematic drawing of an anLibody
`Fig.
`molecule of class IgG I. IL is composed of two identical
`heavy chains and two identical light chains with rnol.
`wts of 50,000 and 25,000, respectively. Both types of
`polypeptide chain are folded into domains: the four
`domains of the heavy chain are VH, CH I, CH2, and
`CH3; the light chain consists of the two domains VL
`and C�. All domains except CH2 are arranged in
`pairs which arc held together· by non -covalent forces.
`Inter-chain disulfide bridges provide further stability.
`Among antibody molecules of a given class and
`species, the V-domains differ considerably in amino
`acid sequence, whereas the C-domains have identical
`sequences. The V-domains are composed of about 110
`amino acid residues at. the N-tcrminal end of heavy
`an<l light chains. The VH-VL pair together forms the
`antigen binding site; differem antibody specificities
`are the result of different amino acid sequences of the
`V-domains. The sequence variability in V-domains is
`most pronounced in a few hypervariablc regions. On
`the other hand the framework residues are well con­
`served. The constant domains CI 12 and Cl-13 are
`involved in effector functions such as compl.ement
`activation and binding to receptors on certain cell
`types. There is significant homology between the
`amino acid sequences of all C-domains, and of 1hc
`framework residues of V -domains.
`Proteolytic cleavage at the hinge region yields stable
`and functional fragments: the antigen-binding rrag­
`rnent P'ab, and the Fe fragment (Fe was the first anti­
`body fragment obtained in crystalline form)6•
`
`A
`
`B
`
`F
`
`E
`
`IGG
`
`H
`
`G
`D
`c
`OF snt.ANDS IN BWHKlGLOSUUH DOMAINS
`ARltANGEMENT
`X N-lfRMJ NUS UP. • C-HRMI NUS IJP
`
`x
`
`Fig. I Schematic represcnlalion of an IgGl immunuglobulio
`
`
`molecule.
`The arms ol' the Y-shaped molecule arc limned by 1he Fab pans,
`Fig. 2 Schcrna1ic drawing of the strand topology in a V­
`
`the s1em is made up by the Fe pan. The ligh1 chains are linked to
`1he heavy chains by a disulphide
`bridge close to the C-tcrminus.
`
`domain viewed parallel to the strands.
`linkages i11
`The two heavy chains arc connected via two disulphide
`ends of the slrnnd� poin1-
`
`(x) and (•) indi«<lle N- and C-terminal
`
`ing LOw<!rdS I he Observer.
`the hinge region.
`
`• £1$evl.;f' KM>m('"(l1nil P11'» 1\1�2
`QOo..oo(l0/$2 l!J
`OJC.7-4QJ<J/82/0
`
`1 of 7
`
`BI Exhibit 1082
`
`

`

`!111mu11olugy Today, wl. 3, Nu. Ii, 1982
`
`161
`
`Besides IgC I, several other classes (IgM, lg!\, lgD,
`IgE) and subclasses of immunoglobulins have been
`identified; the differences between these are located in
`the constant region of the heavy chain. The two types
`of light chain (kappa, lambda) can combine with
`heavy chains of any class.
`
`different immunoglobulin chains. This low deg ree of
`sequence variability for the residues importan1 for
`comacc formation provides an explanation for
`lateral
`the fact that differenl L-chains c.;an associate with
`different f I-chains to give intact irnmunoglobulins.
`In addition to the extensive Van dcr Waals cornacts,
`there exist a few trans hydrogen bonds, in which
`mainly pol<1r side c;h;iin groups are involved. There <1re
`Domain folding
`The general folding pattern in all immunoglobulin
`
`1.wo s;ilt linkages in Kol CL-CHI contact: Glu 125
`domains is very similar. It is shown schematically in
`light chain - Lys 214 heavy chain, Glu 126 light chain
`- .Lys 148 heavy chain, which have their analgon in
`Fig. 2 for a V-domain. The folding is characterized
`by two pleated sheets connected by an internal di­
`CH3 - CT-13 pairing: Glu 356- Lys 439, Glu 357 - Lys
`sulphide bridge linking strands 13 and C. The Lwo
`370.
`sheets cover a large number of hydrophobic amino
`CJ 12 is an exception, as it forms a single unit
`acid side chains.
`without lateral domain interactions (see Fig. 3)*.
`Despite that gross similarity there exist substanlial
`Instead it interacts with bound carbohydrate, which is
`when one compares V- and C-domains:
`attached to Asn 297. The CH2 residues that are
`differences
`C-domains lack strand X, strand D is very short (2-3
`involved in carbohydrate contact are, with a few
`amino acids) and connected to strand E. In addition
`exceptions, structurally in the same positions as the
`the length of the loop regions in C-domains is different
`residues that form the CH3-CH3 contact (face ABFE
`from V-domains, thus changing the overall shape con­
`in Fig. 2). This demonstrates that the carbohydrate
`in CH2 provides a substitute
`siderably.
`f'or the C-C con­
`tact and presumably helps to stabilize the CH2-
`VH and VL, on the other hand, show only minor
`domain. The branched carbohydrate forms a few
`differences when compared with each other (except in
`the hypervariable regions) as do CL, CH I and CH3.
`hydrogen bonds with the CH2-domain, but the dom­
`inant interactions are hydrophobic in nature. The
`
`CH2 represents yet a third type of domain,
`carbohydrate covers a hydrophobic pat.ch of the
`differentiated from the other C-domains mainly by the
`branched carbohydrate chain linked to it. It will be
`protein made up of Phe 241, 243, Val 262, 264, Tyr
`discussed in more detail below.
`296, Thr 260, Arg 301, which would otherwise be
`exposed to the solvent. The loss of accessible surface
`area of one Cl-12 domain is 522 A2, which is only about
`Domain-domain interaction
`Two kinds of domain interactions occur in im muno­
`half as much covered surface area as seen
`in
`lateral (or trans) interactions and longi­
`CII3-CH3 contact (1080 A2). This observation could
`globulins:
`tudinal (or cis) interactions.
`explain the apparent 'softness' of those pans of the
`CH2-domain, as seen in the crystal structureu·1\
`In lateral interactions
`domains
`immunoglobulin
`other than CH2 strongly associate to form modules
`which are most remote from the CH3-CH2 interface.
`VL-VH, CL-CH I, CH3-CH3. In V modules VH
`The functional relevance of carbohydrate in ami­
`may be replaced by VL lo form light chain V dimers
`bodies is unclear. It might be involved in intracellular
`as seen in the Bence-Jones protein fragments Rei or
`movements of the glycoproteins and in secretionlf•.1•. It
`Au7-9• In Bence-Jones proteins, which are light chain
`may well be that the origin of the alte red functional
`dimers, one of the light chains simulates the Fab pans
`properties of carbohydrate-free antibody variants is
`of the heavy chain, as described for Mcg1�.
`structural destabilization.
`V modules associate in a differenL way than C
`ln contrast to the extensive lateral interac.:tions,
`m odules do. In V modules MGCD faces (see Fig. 2) of
`nonbondcd longitudinal interactions along the hcav}
`the domains get into contact, in C modules the /\BFE.
`chain or light chain are much weaker or do not exist al
`faces are involved.
`all. However,
`they arc interes1ing
`because con­
`/\ considerable loss of accessible surl'ace area11 i�
`formational changes in antibodies affect those inter­
`connected with contact formation of the immuno­
`actions.
`globulin domains. It amounts to 1760 A2, 1923 f..2 and
`Fig. 3, which represents the Fe parr ol' .an lg(; I
`21801\2 for VL-VH, CL-CH I modules of IgC KoJIW
`molecule shows the CH2-CH3 interaction. With a
`and
`the CI l3-CH3 module of
`loss in accessible surface area of 778 J..z this wntacl
`an human Fe
`respectively. In VL-VH association both
`has roughly one l hi rd of the size of CH3-CH3 cont11ct.
`fragmem'·'·11
`framework residues and amino acids from hyper­
`The residues that participate in CI-12-CI-13 contact
`variable segments <:u-e involved. I\ comparison of V­
`arc highly conserved in all lg classes,
`suggesting that
`domain amino acid sequences of different animal
`this contact is likely LO be found in IgC and lg/\ 11nd as
`species shows that the contacting framework residues
`CH3-CH4 contact in lgE and IgM.
`are highly conserved. /\lso the consume dom;iin
`•Most t'<:adcrs will need a sicrco viewer (commcrciallr available)
`residues participating
`in lateral conlact arc either
`10 see in three dimensions the structures shown in 1hc paired
`invariant or replaced by homologous residues in
`diagrams on pages J 62, 163 and t 66.
`
`2 of 7
`
`BI Exhibit 1082
`
`

`

`Fig . .3 Stereo drawing of a space
`filling model of human Fe-frag­
`ment.
`Th� molecule is built from
`two
`identical polypeptide ch;iins (chain I,
`chain 2), and identical carbohydrate
`groups. Both halves arc related by
`approximate diads.
`
`Fig. 4 lgG l molecule Kol.
`The Fab parts and the hinge segrnen1 are
`well ordered in the Kol crystals, the Fe part
`is disordered and not visible.
`
`PLEASE NOTE
`We regret that
`for technical reasons it
`has not been possible to reproduce Figs
`3, 4, 6, 7 and 8 with che colour coding
`that allows different parts of the molec­
`ules to be distinguished.
`The
`rull-colour
`diagrams, with
`in
`explanatory legends, can be
`found
`the personal monthly edition of /mm1111-
`ology Today dated June 1982.
`
`D segment
`
`fig. 5 Amino acid comparis on of residues 98-119 (Eu num­
`bering) of M603, New, Kol and Eu heavy chains. The
`underlined residues were left out in Fig. 6c.
`
`End ofVH
`
`98
`Cys Ala Arg
`Cys Ala Arg
`Cys Ala Arg
`Cys Ala Gly
`
`M603:
`New
`Kol
`Eu
`
`Asn Tyr Tyr
`Asn Leu
`lie
`Asp Gly Gly
`Gly Tyr Gly
`
`Gly
`Ala
`His
`lie
`
`Ser
`Gly
`Gly
`Tyr
`
`Thr
`Cys
`lie
`Phe Cys Ser Ser Ala Ser Cys
`Ser
`
`Phe
`
`3 of 7
`
`BI Exhibit 1082
`
`

`

`Fig. 6 Antigen binding region of
`lgGI Kol.
`(a) The extended third hyper­
`variable loop of the heavy chain
`folds into the putative antigen
`binding pocket.
`(b) C a backbone and sidcchains
`of Kol antigen binding pocket.
`(c) Artificial deletion of nine
`in the third hyper­
`residues
`variable segmem of Kol, which
`makes it of equal length with lgG I
`Eu'", reveals a deep curved cleft.
`
`J segment
`
`110
`Try Tyr Phe Asp Val Try Gly
`Asp Val Try Gly
`Asp Tyr Try Gly
`Pro Glu Glu Tyr
`
`Ala Gly Thr Thr
`Gin Gly Ser
`Leu
`Gin Gly Thr Pro
`Asn Gly Gly Leu
`
`119
`Val Thr Val Ser Ser
`Val Thr Val Ser Ser
`Val Thr Val Ser Ser
`Val Thr Val Ser Ser
`
`Gly Pro
`
`4 of 7
`
`BI Exhibit 1082
`
`

`

`IM
`
`/rmm111ology Today, �of. 3, No. fi, IY/i2
`
`The CH2-CH3 orientation is found LO be somc::whaL
`
`caviLy by the first hypervariable loop or L-chain and
`
`loop of H-ehain. The deeper
`
`variable and influe::nced by external forces. In the F<'
`the third hypervariable
`
`
`
`fragment crystals the 1 wo chemically identical chains
`cavity in McPc603, as compared to Fab New, is due to
`
`
`are in a different environment. As a conse::quencc
`
`longer hypervariable loops. The firsl hypervariablc
`
`the CH2-CH3 orientation varies by about 6°. In
`
`region of L-chain and the third hypervariable region of
`Fe-Protein A complex crystals this arrangement
`I I-chain is three residues and the second hypcr­
`from that of Fe crys1als1s.
`differs slightly
`
`variable loop of the H-chain is two residues longer in
`in VI-I-Cl 11 and
`More drastic changes are observed
`Mcl'c603 than in r\ew.
`VL-CL longitudinal contacts, when chemically
`
`
`Phosphorylcholine occupies only a small part of the
`different Fab fragments are compared. These
`
`cavity and interacts via Van der Waals forces, electro­
`
`are most con­differences in longitudinal arrangement
`
`
`static interaciions, and hydrogen bonds with the
`veniently described by an elbow angle, which is
`pro1ein.
`enclosed by the pseudo diads relating VL to VH and
`
`In contrast LO the above examples lgG Kol shows no
`CH1 to CL respectively.
`The elbow angle may vary
`cleft or depression
`region. In
`in 1hc antigen-binding
`from more than 170° to 135° when we compare Kol
`lgG Kol the heavy chain has a rather long third hyper­
`Fab with McPc Fab12-1>.i9.zo.
`variable loop, which contains six residues more than
`In two cases the elbow angles of the same molecule
`
`M603 and eight more residues th;111 Fab New. The
`amino acid sequences of the third hypervariable
`
`were compared aud in two different crystal lallices
`
`found to differ by 8° and 17° respectively19.21. Tn Fab
`regions of M60326, NcwH, Kol2' and Eu28 arc com­
`
`pared in Pig. 5. The sequence alignmc111 and classifi­
`New, with an elbow angle of approximately 137°,
`
`cation in VH, I) and J segment26.i• is somewhat
`
`there exist a few longitudinal contacts between VL
`
`
`arbicrary, especially for the beginning ofthe.J segment
`and CL and VI I and Cl 1122•21, whereas there are no
`
`as a nucleotide sequence has been determined only for
`
`
`non-bonded longitudinal contacts in intact Kol and
`Fab Kol (see Fig. 4), which are characterized
`by an
`
`M6Q326. The additional residues in Kol with the
`
`to open elbow angle. We interpret these observations
`
`nearly palindromic amino acid sequence -Gly-Phc­
`mean that in Fab Kol the V-C arrangement is flexible
`fold into the puta­
`Cys-Ser-Ser-Ala-Scr-Cys-Phc-Gly
`
`in soluLion. In the crys1al the molecule is stablized by
`
`
`tive antigen binding site and fill it completely (sec rig.
`
`packing interactions; these will be discussed from a
`
`6a,b). The two cystcins arr disulphide bridged and
`poinl or view later.
`different
`
`form the start and endpoints of a shon ;1ntiparallel �­
`sheet, comprising residues -Cy�-Scr-Ser-Ala-Scr-Cys-.
`The antigen-binding area
`
`If in a model building experiment nine residues arc cut
`
`Comparison or amino acid sequences of variable
`
`from the third hypcrvariablc region of the Kol heavy
`
`the hypcrvariability of some
`parts has demonstrated
`making it of equal length with lgG I Eu2",
`chain, thus
`
`segments. These were considered to be involved in
`a deep curved cleft appears (Fig. 6c), which easily
`antigen bindingH. Indeed, crystal structure analyses
`could accommodate haptcn�. With respect to the anti­
`of l g fragment-haptcn complexes show that haptens
`
`gen binding area lgG Kol 1hus looks as if it carried its
`bind in a cleft or depression formed by the hyper­
`own haptcn in form of an extended third hype::r­
`variablc segments.
`
`
`variablc loop. Another peculiarity of lgG Kol mighi be
`The VL dimer of Rei7•9 may serve as an illustrative
`
`
`the of interes1 in that context. In the Kol crystal lattice
`examplt:. The symmetrically arranged hypervariablc
`
`
`hypcrvariablc parts of one molecule !Ouch the hinge
`regions form a deep slit-like pocket around the diad
`
`
`
`and spa1ially ac\jacent segments of a symmetrically
`relating lhe two VL monomers. The walls of the sliL
`related molecule. This contact consists of three salt
`49, 91, 96, /\sn 34 and Gin 89;
`are lined by tyrpsincs
`linkages (Arg 49 light chain-COOH light chain, Asp
`the bottom of the pocket is formed by Tyr 36 and Gin
`50 light chain-Arg 215 heavy chain, /\sp 53 heavy
`
`89. A trinitrophcnyl group binds to the Rei fragment
`
`ch;1in-Lys 134 heavy chain). a few hydrogen bonds
`and fills the binding pocke1 completely.
`
`and extensive Van der \Vaals interactions. Thus, che
`Another example of an IgG fragment haptcn
`lauice contact found in Kol crystals might give an
`complex is Fab Ne", which is known to bind among
`instructive
`model for antibody-an1igen interaction, as
`
`
`other ligands a hydroxy derivative of vitamin K,2\.
`antigens arc usually macromolecules which cover
`a
`The hypervariable segments of l'\cw form a �hallow
`much larger part of the antibody than haptcns do.
`
`groove wit� approxima1c dimensions
`of 16 x 7 A O:Jnd a
`depth or 6 I\.
`The hinge segment
`McPc 603, a mouse lg/\ (K) Fab fragme11t211 uinds
`The hinge segment which covalcndy links Pab and
`phosphorylcholine.
`The site or hapten binding is �·
`Fe parts, has a unique primnry and spatial structure.
`
`large wedge shape� cavity, with dimensions 15 x 20 A
`
`Its central region consists of two parallel disulphide­
`and a depth of' 12 A. Only five of the six hypcrvariablc
`
`linked poly L-prolinc helices wirh an amino acid
`1l.I '. In the lgG I subclass
`
`regions contribuLe to the formation of the cavity: L­
`sequence -Cys-Pro-Pro-Cys-
`
`
`chain hypervariable regions one and three, and all
`by the Kol molecule the poly-proline
`represented
`double helix is short (Fi�. 7). However, in lgG3 the
`
`three H-chain hypervariable regions. The second
`
`hypervariablc region of L-chain is screened from 1hc
`
`hinge sequence is quadruplicated'" and model build-
`
`5 of 7
`
`BI Exhibit 1082
`
`

`

`Immunology Today, uol. 3, Nv. 6, 1982
`
`165
`
`ing suggests that the poly-prolinc segment of this
`molecule may be more than 100 A long.
`The poly-proline segment, a relatively rigid struc­
`rurc, is Aanked on both sides by Acxible segments: The
`segment on the N-terminal side is well defined in the
`crystal lattice or Kol due LO crystal packing inter­
`actions, but it lacks internal interactions, that would
`provide stability in solution. The C terminal segment
`is di�ordcrcd and Acxiblc in Kol crystals and in 1 he Fe
`crystal structurc11.1�. The rigid hinge segment allows
`independent movement of the Fab arms and the Fe
`part. There is direct evidence for flexibility in the
`crystal lattice of Kol''-19 and Zie3'. This is in contrast
`to the abnormal lgG protein Dob, which lacks a hinge
`rcgion32• The significance of the hinge for Fab-Fc
`flexibility is obvious.
`
`Complement binding
`The binding of the Clq component of the Cl
`complex to antigcn-ancibody complexes is the first
`in
`the classical pathway of complement
`step
`activation 13·3 '· The Clq head pieces bind to the CH2
`domains of antibodies3·1•3". Protein /I., a constituent of
`the cell wait of Staphylococcus aureus, binds LO the Fc­
`part of antibody molecules of certain classes and sub­
`classes, but does not
`interfere with complement
`binding. The determination of the crystal structure of
`the complex between FB (one of the four Fe-binding
`domains of protein AH) and Fe-fragment showed that
`protein A binds al the Cl 12-CH3 contact•S.Js. Fig. 8
`shows a space-filling model of the FB-Fc complex.
`The area of CH2 not covered by FB must contain the
`Clq binding site. In view of 1hc size of the Clq he<1d
`pieces (mo!. wt 50,000) it appears unlikely that they
`can bind at the inner sides of CH2, i.e. near the carbo­
`hydrate. The most plausible binding site is therefore
`near the tip of CH2 on the outer side of the domain. It
`is worth mentioning that this region is disordered in
`crystals of' the FB-Fc complex which indicates th<tt
`this part of the CH2 domain is flexible. Possibly,
`flexibility is required for antibody Clq interaction.
`
`Summary and perspectives
`Investigations of the three-dimensional architecture
`of ;mtibodies h11ve elucidated the folding of the
`polypeptide chains into domains, and the spatial
`arrangement of the domains. The structural basis for
`understanding antibody specificity and antibody
`Aexibility was obtained. Segmental flexibility is an
`important property of amibodics: Flexible segments of
`the polypeptide chains at the switch and hinge regions
`allow the !"ab fragments to change their shape and
`their relative orientation. Conformationill changes of
`this kind are necessary to meet the geometric require­
`ments which arise on binding of antibodies to multi­
`valent antigens.
`The undersrnnding of the effector functions of anti­
`body molecules is much less complete. One of the
`central problems is the explan:-ition of the strong
`enh:-incement of Clq binding to antigen-antibody
`
`complexes as compared to free antibody molecules.
`Two mechanisms have been considered (for a review
`see Ref. 39): since Clq is multimeric with at least six
`antibody binding sites, binding may be enhanced by
`the form<1tion of antigen-antibody aggregates through
`crosslinking. Alternatively, antigen binding might
`induce a conformational change in the Fe-part which
`enhances affinity for Clq.
`There is strong evidence for the importance or
`aggregation, but a mixed mechanism which involves
`aggregation and a conformational change cannot be
`ruled out.
`The studies described here were almost exclusively
`carried out with myeloma or Hence-Jones proteins
`because these were 1he only homogeneous irnmuno­
`globulins which could be obtained
`in sufficient
`quantity. However, in most cases the specificities of
`such molecules is unknown. Recently, large amounts
`or homogeneous antibodies elicited against strepto­
`coccal or pneumococcal polysaccharides became
`available from cenain rabbit and mouse strains"'·"'.
`These sources, and the use of hybrids obtained from
`myeloma and spleen cells have made it possible to
`obtain homogeneous antibodies of defined speci­
`ficity·•?.•�. Structural studies of 'natural' antigen-anti­
`body complexes can be expected to lead to a more
`complete understanding of antibody
`function.
`Crystallographic work on a specific antibody and of its
`antigen is already in progress44•
`
`Acknowledgements
`We thank Prof. R. Huber for helpful discussions.
`
`References
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`2 Porter, R. R. ( 1976) Sri. Am. Oc1obcr, 81-87
`3 Hilschmann,N. (1%9).V11111rwi.r.1msdlflflm56,
`19S-205
`4 F.dmundson, /\. B., Ely, K. R. and Ahola, E. £. (1978) 01111.
`To/1 . .lfnl. b1111111111Jf. 7, 95-118
`5 1\m7.el, L. M. and Poljak. R. J. (1?79) Ann. Rn·. l/i1Jr/1m1. 48,
`961-997
`/,md1m) 182, 670-671
`6 Porter. R.R. (1958)..V11l1ur(
`7 Epp, O .. Colman. P. M., Fchlh<1mmcr, H., Bode, W., Schiffer,
`:--� .. Huber, R. and P<ilm. W. (1974) J\11r. ]. /Jinrhm1. 45,
`513-524
`8 Fehlhammer, t I., Schiffer, M., Epp, 0., Colman. P. M . .
`l.auman, E. E., Schwager, I'., Stcigcmann, W. and Schramm,
`1 l..J. (1975) /Jin/1/i)'·'· Strn/'/ . .lfrd11111i.wu I, 139-146
`9 Epp, 0., Laurnan, I�. E., Schiffer, M., Huber, R. and Palm.
`W. (1975) 8i1Jdmnistn•
`14, 4943-4?52
`10 Edmundson, /\. B., Ely, K. R., /\bola, R. R., Schiffer, M. and
`Paniagia1npoulos. N. (t975) llinc"hmn<I')'
`14, 3953-J961
`11 Lee, B. mid Ri<:hards, F. M. (1970)].
`.\In/. Jim/. 55, 379-400
`t2 Colman, I'. M .. Deisenhofcr, .J .. Huber, R. and Palm. W.
`(1976)] . . lfo/. /lfo/. 100. 257-282
`13 Marquart, M., Deiscnhofcr, J., Huber, R. and P�lm. W.
`(I 980)]. ,\/11/. /Jin/. 141. 369-392
`14 Dciscnhofcr,.J., Colman, P. M., F.pp, 0. and Huber-, R. (1976)
`H11f'lir- .\r.rifr\ ,(. l'h1•.<i11f. 01r111. 357, 1421-1434
`I 5 Dei�cnhofcr,J. ( 1981) Hi1H-lll'1ui.<lr.v 20, 2361-2370
`16 !'l'lclchers, F. (1?73) lli11rhr11111/TJ'
`12, 1471-t47(1
`17 Weitzman, S. and Scharf1, �I. D. ( 1976)]. .lfol. /Jwl. 102,
`237-252
`II! Hickman,!:>., Kukzycki, /\ . .Jr, 1.ynch, R. G. and Kornfeld, S.
`c 1977)]. 11;"'· u,,111. 2s2. 4402-4408
`
`6 of 7
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`BI Exhibit 1082
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`

`

`Fig. 7 Conformation of the hinge
`region as seen in IgCI Kol.
`
`Fig. 8 Space filling model of
`the FS (protein A) - Fe
`complex.
`
`19 Matsushima, M., Marquart, M.,Jones, T. A., Colman, P. M.,
`Bartels, K., Huber, R. nnrl Palm, W. (1978) J. Mn/. BitJI. 121,
`441-459
`20 Segal, I). M., Padlan, E. /\., Cohen, G. H., RudikoIT. S.,
`Potter, M. and Davies, D.R. (1974) Pmc. Nall Acarl. Sci. U.S.A.
`71,4298-4302
`21 /\bola, E. E., l::ly, K. R. and Edmundson, A. B. ( 1980)
`B1'telmmslry 19, 432-439
`22 Poljak, R. J., Anncl. L. M., Chen, B. (,., Phiackerley. R. P.
`and Saul, F. (1974) !'me. Nntl Acnd. Sci. U.S.A. 71, 3440-3444
`23 Saul, F., Arnzcl, l,. M. and Poljak, R. J. ( 1978)]. I/in/. Clum.
`253, 585-597
`24 Wu, T. T. and Kabat, E. /\. (1970)]. /lrp. Mttl 132, 211-250
`25 /\mzel, L. M., Poljak, R. j.. Saul, F .. Varga, J. M. and
`Richards. F. F. (I 974) Proc. Nall Acad. Sci. U.S.A. 71,
`1427-1430
`26 Eady, P., Huang, H., Oavis, M., Calame, K. and Hood, L.
`(1980) Cell 19, 981-992
`27 Schmidt, W., Jung, H. D., Palm, W. and Hilschmann, N.
`(1981) private communication
`28 Cunningham, B. /\., Rutishauser, U., Gall, W. E., Cottlicb,P.
`D., Waxdal, M. J. and Edelman, G. M. (1970) /Jiochenustry '>,
`3161-3170
`29 Sakano, H., Maki, R., Kurosawa, Y., Roeder, W. and
`Toncgawa, S. (1980) N11ture ( l,ondo11) 286, 676-683
`30 Michaelson, T. E., Frangione, B. and Franklin, E. C. (1977)
`]. Ri11l. (.'hm1. 252, 883-889
`
`3 I Ely, K. R., Colman, P. M., A bola, E. E., Hess, 1\. C., l'cabody,
`D. S., Parr, D. M., Connell, G. E., Lauschinger, C. /\. and
`Edmundson, A. B. (I 978) 8i.11chm1iflry 17. 820-823
`32 Silverton, E: W., Navia, M.A. and Davies, D.R. (1977) Pwr.
`Nall Arorl. Sci. U.S.A. 74, 5140-5 I 44
`33 Mueller-Eberhard, H.J. (1975) 111111. Rev. Bfocllrm. 44, 697-724
`34 .Porter, R. R. and Reid, K. 13. M. (1979) Adv. Pmt. Cltem. 33,
`1-71
`35 Connell, C. E. and Porter, R. R (197 I) llwchm1. ]. 124, 53P
`36 Yasmeen, D., Ellerson, J. R., Dorrington, I<. J. and Paimer,R.
`H. (1976}]. lmmtmt1/. 116, 518-526
`37 Sjocdahl,J. (1977) far.J. lJiochem. 78, 471-490
`38 Oeisenhofcr, J., Jones, T. /\., Huber, R., Sjoedahl, .J. and Sjoe·
`quist,J. (1978) z. !'hysio/. (:hem. 359, 975-985
`39 Metzger, J-1. (1978) Ctmt. Top. Mo/. lmrmmol. 7, 119-148
`40 Jaton, J.-C., Huser, H., Braun, D. C., Ci vol, D., P�dll,J. ;u1d
`Schlessingcr,J. C. (1975) Bif)(/tr.mi.1try 14, 5312-5315
`41 Braun, D. G. and Huser, H. (1977) in f>mgress in lmmwwfflgy If/
`(Mandel,'!'. E., Cheers, C.H., Hosking, C. S .. McKenzie,[. F.
`C. and Nossa!, G. J. V., eds) pp. 255-264, l::lsevier North·
`Holland, Amsterdam, New York, Oxford
`42 Kuchler, G. and Mils1cin, C. (1975) Na11m ( l.1mdrm) 256,
`495-497
`43 Melchers, F., Potter, B. M. and Bethesda, N. W. (eds) (1978)
`C11rr. Top. Microbfol. lmmwlfll. 81
`44 Colman, P. M., Gough, K. H., Lilley, G. G., Ulagrove, R . .J.,
`Webster, R. C. and Laver, W. G. (1981) J. Mo/. Bini. 152,
`609--014
`
`7 of 7
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`BI Exhibit 1082
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