title: Gender differences in the immune system activities of sea urchin Paracentrotus lividus.
abstract: In the immune system of vertebrates, gender-specific differences in individual immune competence are well known. In general, females possess more powerful immune response than males. In invertebrates, the situation is much less clear. For this purpose we have chosen to study the immune response of the two sexes of the echinoderm Paracentrotus lividus in pre- and post-spawning phases. The coelomic fluid from the echinoderms contains several coelomocyte types and molecules involved in innate immune defenses. In this article we report that the degree of immune responses in the P. lividus differs according to sex in both pre- and post-spawning phases. We found in all tests that females were more active than males. The results indicate that females possess a significant higher number of immunocytes consisting of phagocytes and uncolored spherulocytes. Since the immunological activity is mainly based on immunocytes, it was not surprising that females possessed the highest values of cytotoxicity and hemolysis activity and showed a greater ability to uptake neutral red and phagocyte yeasts cells, while the average number of ingested particles per active phagocyte was not significantly different. Furthermore, agglutinating activity was more evident in the coelomocyte lysate and coelomic fluid of females than in those of males. Finally we found that the acidic extract of female gonads possessed greater antimicrobial activity than that of male gonads. These results make it very likely that gender differences in the immune response are not restricted to vertebrates; rather, they are a general evolutionary phenomenon.
authors.affiliation: Dipartimento di Biologia ambientale e Biodiversità, Università degli Studi di Palermo, Via Archirafi, 18-90123 Palermo, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Arizza
authors.forename: Mirella
authors.initials: M
authors.lastname: Vazzana
authors.forename: Domenico
authors.initials: D
authors.lastname: Schillaci
authors.forename: Debora
authors.initials: D
authors.lastname: Russo
authors.forename: Francesca Tiziana
authors.initials: FT
authors.lastname: Giaramita
authors.forename: Nicolò
authors.initials: N
authors.lastname: Parrinello
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000302:isolation & purification / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides / Q000302:isolation & purification / Q000494:pharmacology; D002452:Cell Count; D002457:Cell Extracts / Q000737:chemistry; D002478:Cells, Cultured; D004396:Coloring Agents / Q000378:metabolism; D003602:Cytotoxicity, Immunologic; D004912:Erythrocytes / Q000276:immunology; D005260:Female; D006066:Gonads / Q000737:chemistry / Q000378:metabolism; D006384:Hemagglutination; D006461:Hemolysis; D007113:Immunity, Innate; D008297:Male; D008826:Microbial Sensitivity Tests; D009499:Neutral Red / Q000378:metabolism; D047328:Paracentrotus / Q000737:chemistry / Q000166:cytology / Q000276:immunology*; D010586:Phagocytes / Q000737:chemistry / Q000166:cytology / Q000382:microbiology; D010587:Phagocytosis; D011817:Rabbits; D012441:Saccharomyces cerevisiae / Q000276:immunology; D012727:Sex Characteristics; D012732:Sex Determination Analysis; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; D002457:Cell Extracts; D004396:Coloring Agents; D009499:Neutral Red