Immunoregulatory activity of substance P fragments.
The C-terminal SP7-11 pentapeptide (Phe-Phe-Gly-Leu-Met-NH2) was found to suppress in vitro the immune response in a dose of 1-5 micrograms/ml. It produced also a distinct immunosuppression in vivo, by both per os and intraperitoneal, applications. In contrast, the N-terminal SP1-4 fragment (Arg-Pro-Lys-Pro) suppressed the response at a dose of 0.1 microgram/ml, but stimulated it slightly at higher doses (1-5 micrograms/ml). A structural analog of SP1-4 (Gly-Pro-Arg-Pro tetrapeptide) was found to be a strong immunosuppressor at a dose of 5 micrograms/ml, indicating the importance of N-terminal basic residue for the immunoregulatory activity of intact SP.
Siemion
I Z
IZ
Institute of Chemistry, Wrocław University, Poland.
Nawrocka
E
E
Słoń
J
J
Pedyczak
A
A
Kubik
A
A
Spiegel
K
K
Zimecki
M
M
Wieczorek
Z
Z
D000595:Amino Acid Sequence; D000818:Animals; D006462:Hemolytic Plaque Technique; D007109:Immunity / Q000502:physiology*; D051379:Mice; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000502:physiology; D010455:Peptides / Q000138:chemical synthesis; D013154:Spleen / Q000166:cytology / Q000276:immunology; D013373:Substance P / Q000031:analogs & derivatives / Q000502:physiology*
D010446:Peptide Fragments; D010455:Peptides; D013373:Substance P