Genco C A, Odusanya B M, Potempa J, Mikolajczyk-Pawlinska J, Travis J
Department of Microbiology and Immunology, Morehouse School of Medicine, Atlanta, Georgia 30310-1495, USA.
Infect Immun. 1998 Sep;66(9):4108-14. doi: 10.1128/IAI.66.9.4108-4114.1998.
The cysteine proteinases referred to as gingipains R (gingipain R1 and gingipain R2) and gingipain K produced by Porphyromonas gingivalis are virulence factors of this periodontal pathogen which likely act by interrupting host defense mechanisms and by participating in the penetration and destruction of host connective tissue. To examine the effect of immunization with gingipains R on the ability of P. gingivalis to colonize and invade in the mouse chamber model, BALB/c mice were immunized intraperitoneally with the 95-kDa gingipain R1, the 50-kDa gingipain R2, or multiple antigenic peptide (MAP)-conjugated gingipain R-derived peptides and then challenged with P. gingivalis. Immunization of mice with the 95-kDa gingipain R1, the 50-kDa gingipain R2, or a peptide derived from the N-terminal sequence of the catalytic domain of gingipains R (peptide A) followed by challenge with P. gingivalis A7436 resulted in protection from P. gingivalis invasion. In contrast, immunization with peptides corresponding to either a sequence encompassing the catalytic cysteine residue of gingipains R (peptide B) or an identical sequence within the catalytic domains of gingipain R1 and gingipain K (peptide C), followed by challenge with P. gingivalis, did not protect animals, nor did immunization with a peptide corresponding to sequences within the adhesion/hemagglutinin domain of gingipain R1 (peptide D) which have been shown to be directly involved in the hemagglutinin activity of gingipain R1. However, the immunoglobulin G (IgG) titer obtained following immunization with peptide D was comparable to that obtained following immunization with the N-terminal peptide (peptide A). Competitive enzyme-linked immunosorbent assays, using either the 95-kDa gingipain R1 or gingipain K as the competing soluble antigen, indicated that 42 and 53% of the antibodies induced by immunization with heat-killed bacteria recognize gingipain R1 and gingipain K, respectively; however, even at very high concentrations, the 50-kDa gingipain R2 did not hinder IgG binding to P. gingivalis. These results indicate that antibodies directed to the amino-terminal region of the catalytic domain of gingipains R are capable of inducing a protective immune response against P. gingivalis infection in the mouse chamber model.
牙龈卟啉单胞菌产生的半胱氨酸蛋白酶，即牙龈蛋白酶R（牙龈蛋白酶R1和牙龈蛋白酶R2）和牙龈蛋白酶K，是这种牙周病原体的毒力因子，它们可能通过干扰宿主防御机制以及参与宿主结缔组织的渗透和破坏来发挥作用。为了研究用牙龈蛋白酶R免疫对牙龈卟啉单胞菌在小鼠腔室模型中定植和侵袭能力的影响，将BALB/c小鼠腹腔注射95 kDa的牙龈蛋白酶R1、50 kDa的牙龈蛋白酶R2或多抗原肽（MAP）偶联的牙龈蛋白酶R衍生肽，然后用牙龈卟啉单胞菌进行攻击。用95 kDa的牙龈蛋白酶R1、50 kDa的牙龈蛋白酶R2或源自牙龈蛋白酶R催化结构域N端序列的肽（肽A）免疫小鼠，随后用牙龈卟啉单胞菌A7436攻击，可使小鼠免受牙龈卟啉单胞菌的侵袭。相比之下，用与牙龈蛋白酶R催化半胱氨酸残基序列（肽B）或牙龈蛋白酶R1和牙龈蛋白酶K催化结构域内相同序列（肽C）对应的肽免疫，随后用牙龈卟啉单胞菌攻击，并不能保护动物，用与牙龈蛋白酶R1黏附/血凝素结构域内序列对应的肽（肽D）免疫也不能保护动物，肽D已被证明直接参与牙龈蛋白酶R1的血凝素活性。然而，用肽D免疫后获得的免疫球蛋白G（IgG）滴度与用N端肽（肽A）免疫后获得的滴度相当。使用95 kDa的牙龈蛋白酶R1或牙龈蛋白酶K作为竞争可溶性抗原的竞争性酶联免疫吸附测定表明，用热灭活细菌免疫诱导的抗体分别有42%和53%识别牙龈蛋白酶R1和牙龈蛋白酶K；然而，即使在非常高的浓度下，50 kDa的牙龈蛋白酶R2也不会阻碍IgG与牙龈卟啉单胞菌的结合。这些结果表明，针对牙龈蛋白酶R催化结构域氨基末端区域的抗体能够在小鼠腔室模型中诱导针对牙龈卟啉单胞菌感染的保护性免疫反应。
