title: Immunogenicity studies of proteins forming the T4 phage head surface.
abstract: Advances in phage therapy and novel applications of phages in biotechnology encourage interest in phage impact on human and animal immunity. Here we present comparative studies of immunogenic properties of T4 phage head surface proteins gp23*, gp24*, Hoc, and Soc, both as elements of the phage capsid and as isolated agents. Studies comprise evaluation of specific antibodies in the human population, analysis of the proteins' impact on the primary and secondary responses in mice, and the effect of specific antibodies on phage antibacterial activity in vitro and in vivo in mice. In humans, natural antibodies specific to T4-like phages were abundant (81% of investigated sera). Among those, significantly elevated levels of IgG antibodies only against major head protein (gp23*) were found, which probably reflected cross-reactions of T4 with antibodies induced by other T4-like phages. Both IgM and IgG antibodies were induced mostly by gp23* and Hoc, while weak (gp24*) and very weak (Soc) reactivities of other head proteins were noticed. Thus, T4 head proteins that markedly contribute to immunological memory to the phage are highly antigenic outer capsid protein (Hoc) and major capsid protein (gp23*). Specific anti-gp23* and anti-Hoc antibodies substantially decreased T4 phage activity in vitro and to some extent in vivo. Cooperating with antibodies, the immune complement system also contributed to annihilating phages.
  
  
  OBJECTIVE
  Current descriptions of phage immunogenicity and its biological consequences are still vague and incomplete; thus, the central problem of this work is timely and may have strong practical implications. Here is presented the very first description of the contribution of bacteriophage proteins to immunological memory of the phage. Understanding of interactions between phages and mammalian immunology may help in biotechnological adaptations of phages for therapeutic requirements as well as for better appreciation of phage ecology and their role in the biosphere.
authors.affiliation: Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland dabrok@iitd.pan.wroc.pl.
authors.forename: Krystyna
authors.initials: K
authors.lastname: Dąbrowska
authors.affiliation: Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.
authors.forename: Paulina
authors.initials: P
authors.lastname: Miernikiewicz
authors.affiliation: Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Piotrowicz
authors.affiliation: Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Hodyra
authors.affiliation: Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.
authors.forename: Barbara
authors.initials: B
authors.lastname: Owczarek
authors.affiliation: Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.
authors.forename: Dorota
authors.initials: D
authors.lastname: Lecion
authors.affiliation: Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland.
authors.forename: Zuzanna
authors.initials: Z
authors.lastname: Kaźmierczak
authors.affiliation: Winogradsky Institute of Microbiology, RAS, Moscow, Russia.
authors.forename: Andrey
authors.initials: A
authors.lastname: Letarov
authors.affiliation: Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland Institute of Transplantology, Medical University of Warsaw, Warsaw, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Górski
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D017122:Bacteriophage T4 / Q000276:immunology*; D003165:Complement System Proteins / Q000276:immunology; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D014764:Viral Proteins / Q000276:immunology*; D055815:Young Adult
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D014764:Viral Proteins; D003165:Complement System Proteins