Immunogenicities of Gonococcal Protein Ii

Gonococci (Gc) 1 vary widely in their outer m e m b r a n e pro te in II (P.II) const i tu t ions (I , 2). Some Gc exhibi t no P.II; o ther Gc of the same strain have one or several different P.II. Each P.II can be present a lone or in combina t ion with o ther P.II. Several P . I I subuni t molecu la r weight forms have been descr ibed wi th in ind iv idua l s trains and a m o n g different strains of Gc (1, 3, 4). All P.II have c o m m o n character is t ics inc luding suscept ibi l i ty to proteolysis, surface exposure, and "hea t modi f i ab i l i ty" (4). Fur the rmore , different P.II are s t ruc tura l ly s imi lar as deduced from 125I-peptide maps of e lec t rophore t ica l ly separa ted P.II bands (5). But different P.II have differing a p p a r e n t effects bo th on colony opac i ty (1, 4) and on the adherence of Gc to eucaryot ic cells (3, 6-10). S t ruc tu ra l differences a m o n g P.II are found by 125I-peptide m a p p i n g (5) especial ly when the prote ins are r ad io labe led in situ on intact Gc (11). The present s tudy explores the ant igenic and immunogen ic re la t ionships of P.II in general , wi th pa r t i cu l a r a t t en t ion to the surface-exposed por t ions of these Gc outer m e m b r a n e consti tuents.