Science 28Feb2020

these fundamentally important questions in
mucosal immunity.

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ACKNOWLEDGMENTS

We thank N. Lombana for ordering constructs, Research

Materials Group for protein expression, F. Farahi and A. Gill for

small-scale purification, A. Estevez and M. Kschonsak for data

collection and discussions, and A. Rohou and B. Barad for

assistance with data processing.Funding:This work was

funded by Genentech, Inc.Author contributions:N.K.:

conceptualization; data curation; formal analysis; investigation;

validation; visualization; writing original draft; writing, review,

and editing; C.P.A.: data curation; investigation; supervision;

C.C.: supervision; writing original draft; writing, review, and

editing; M.L.M: conceptualization; investigation; formal analysis;

project administration; supervision; validation; visualization;

writing original draft; writing, review, and editing;Competing

interests:All authors are employees of Genentech, Inc., a

member of the Roche Group, and may hold stock and options.

C.C. and M.L.M. are inventors on unpublished patent

applications that relate to IgA antibodies and IgG-IgA fusion

molecules and methods of making and using them.Data and

materials availability:All maps and coordinate models have

been deposited to the Worldwide Protein Data Bank: sIgA1 dimer

(EMD-20749, PDB ID 6UE7); sIgA2m2 tetramer class 1 (EMD-

20750, PDB ID 6UE8); sIgA2m2 tetramer class 2 (EMD-20751,

PDB ID 6UE9); sIgA2m2 pentamer (EMD-20752, PDB ID 6UEA).

Materials used in this study are available under a material

transfer agreement from Genentech, Inc.

SUPPLEMENTARY MATERIALS

science.sciencemag.org/content/367/6481/1008/suppl/DC1

Materials and Methods

Figs. S1 to S9

Table S1

References ( 20 – 34 )

20 September 2019; accepted 24 January 2020

Published online 6 February 2020

10.1126/science.aaz5807

Kumaret al.,Science 367 , 1008–1014 (2020) 28 February 2020 7of7

RESEARCH | RESEARCH ARTICLE