TY - JOUR

T1 - Secretory immunoglobulin A from human milk hydrolyzes 5 histones and myelin basic protein

AU - Kompaneets, Ivan Yu.

AU - Sedykh, Sergey E.

AU - Buneva, Valentina N.

AU - Dmitrenok, Pavel S.

AU - Nevinsky, Georgy A.

N1 - Funding Information: This study was supported by the Russian Science Foundation (no. 19-15-00145; Moscow, Russia) and the grant of Russian State-funded budget project AAAA-A17-117020210023-1 (salary for work performers; Novosibirsk, Russia). The authors have not stated any conflicts of interest. Publisher Copyright: © 2022 American Dairy Science Association

PY - 2022/2

Y1 - 2022/2

N2 - Mother's milk provides newborns with various nutri-ents (e.g., enzymes, proteins, peptides, hormones, anti-bo dies) that help babies grow and protect them from bacterial and viral infections. The functions of many components of breast milk can be very different from their corresponding functions in body fluids of healthy adults. Catalytic antibodies (abzymes) that hydrolyze peptides, proteins, DNA, RNA, and oligosaccharides were detected not only in human milk, but also in the blood sera of autoimmune patients. However, abzymes with unexpected synthetic activities (lipids, oligosac-charides, and protein kinase activities) were revealed in milk that were not found in the blood of autoimmune patients. The nutrition of infants with fresh milk has a very specific role; newborns are well protected by an-tibodies of mother's milk (passive immunity). Protease abzymes were found in the blood sera of autoimmune patients, whereas healthy humans usually do not con-tain such autoantibodies. Here, we present the first evi-dence that the milk of healthy mothers contains secre-tory (s)IgA that effectively hydrolyze 5 histones (e.g., H1, H2A, H2B, H3, and H4) and myelin basic protein (MBP). Several rigid criteria were applied to show that protease activity is an intrinsic property of sIgA. Milk abzymes against 5 histones cannot hydrolyze different control proteins except histones and MBP, whereas autoantibodies against MBP split this protein and 5 histones. Antibodies against histones and MBP exhibit complexation polyreactivity as well as specific and un-usual catalytic cross-reactivity. With some exceptions, the specific sites of hydrolysis of H1, H2A, and H2B by sIgA against histones do not coincide with the sites of hydrolysis by abzymes against MBP. On the whole, fresh human milk is a very specific source of many of the most unusual antibodies and abzymes.

AB - Mother's milk provides newborns with various nutri-ents (e.g., enzymes, proteins, peptides, hormones, anti-bo dies) that help babies grow and protect them from bacterial and viral infections. The functions of many components of breast milk can be very different from their corresponding functions in body fluids of healthy adults. Catalytic antibodies (abzymes) that hydrolyze peptides, proteins, DNA, RNA, and oligosaccharides were detected not only in human milk, but also in the blood sera of autoimmune patients. However, abzymes with unexpected synthetic activities (lipids, oligosac-charides, and protein kinase activities) were revealed in milk that were not found in the blood of autoimmune patients. The nutrition of infants with fresh milk has a very specific role; newborns are well protected by an-tibodies of mother's milk (passive immunity). Protease abzymes were found in the blood sera of autoimmune patients, whereas healthy humans usually do not con-tain such autoantibodies. Here, we present the first evi-dence that the milk of healthy mothers contains secre-tory (s)IgA that effectively hydrolyze 5 histones (e.g., H1, H2A, H2B, H3, and H4) and myelin basic protein (MBP). Several rigid criteria were applied to show that protease activity is an intrinsic property of sIgA. Milk abzymes against 5 histones cannot hydrolyze different control proteins except histones and MBP, whereas autoantibodies against MBP split this protein and 5 histones. Antibodies against histones and MBP exhibit complexation polyreactivity as well as specific and un-usual catalytic cross-reactivity. With some exceptions, the specific sites of hydrolysis of H1, H2A, and H2B by sIgA against histones do not coincide with the sites of hydrolysis by abzymes against MBP. On the whole, fresh human milk is a very specific source of many of the most unusual antibodies and abzymes.

KW - human milk

KW - abzyme

KW - hydrolysis

KW - histone

KW - myelin basic protein

KW - SYSTEMIC-LUPUS-ERYTHEMATOSUS

KW - CATALYTIC ANTIBODIES

KW - MULTIPLE-SCLEROSIS

KW - COLONY FORMATION

KW - KINASE-ACTIVITY

KW - SERA

KW - PREGNANCY

KW - AUTOIMMUNE

KW - DNA

KW - IGGS

KW - Immunoglobulin A, Secretory

KW - Immunoglobulin G/metabolism

KW - Myelin Basic Protein/metabolism

KW - Humans

KW - Hydrolysis

KW - Animals

KW - Milk, Human/metabolism

KW - Histones

UR - http://www.scopus.com/inward/record.url?scp=85119427333&partnerID=8YFLogxK

UR - https://www.elibrary.ru/item.asp?id=47530424

U2 - 10.3168/jds.2021-20917

DO - 10.3168/jds.2021-20917

M3 - Article

C2 - 34802738

VL - 105

SP - 950

EP - 964

JO - Journal of dairy science

JF - Journal of dairy science

SN - 0022-0302

IS - 2

ER -