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J M Griffiss

Publications and source records attributed to J M Griffiss.

At least 73 records · Page 4Linked to original sources
PubMed1987

The immunochemistry of neisserial LOS.

The outer membrane glycolipids of Neisseria lack long polysaccharides and are properly termed lipooligosaccharides (LOS). A Neisseria strain makes from two to six LOS of Mr 3150-7100. Different species commonly make LOS of identical Mr and epitope content. Oligosaccharide (OS) differences account for physical heterogeneity. OS consist of a conserved triantenary basal oligosaccharide, two linear segments of (n) hexose residues that determine OS mass, and terminal sequences similar to those of glycosphyngolipids. Epitope expression is linked to physical heterogeneity and conditioned by the molecular environment of the outer membrane. Serotype epitopes are expressed on Mr-restricted LOS. LOS regulate complement activation onto the bacterial surface and, hence, immune lysis.

Antigens, Bacterial↗
PubMed1987

Phenotypic variation in epitope expression of the Neisseria gonorrhoeae lipooligosaccharide.

Gonococcal lipooligosaccharides (LOSs) are a series of antigenically complex heteropolymers. To investigate whether all members of clonally selected populations of Neisseria gonorrhoeae express antigenically similar LOS, we studied gonococcal strains 4505 and 220 with monoclonal antibodies 6B4 and 3F11 which have specificity for different oligosaccharide epitopes on the same or comigrating LOS unit(s) on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Fluorescent-antibody and immunoelectron microscopy studies indicated that all members of the clonally selected populations were not homogenous for the epitopes these antibodies recognized. Fluorescence-activated cell sorting studies of 3F11-coated strain 220 indicated that the density of epitope expression was a function of time of growth. The population could be separated into two broad groups corresponding to organisms staining strongly or weakly for the 3F11 epitope, and the epitope density decreased during the late-log and stationary phases of growth. Sequentially staining organisms on Formvar grids with 6B4 and 3F11, followed by staining with either 5- or 15-nm colloidal gold spheres conjugated to goat anti-mouse immunoglobulin M demonstrated the following populations of cells among organisms derived from a single clone: organisms which stained for both 6B4 and 3F11 epitopes and organisms which stained for either 6B4 epitopes alone or 3F11 epitopes alone. Immunofluorescence microscopy studies with rhodamine and fluorescein goat anti-mouse immunoglobulin M conjugates sequentially staining organisms on Formvar grids with 3F11 and 6B4 also demonstrated these three populations. Analysis of LOS preparations made over the last 5 years indicated no change in serotype antigen concentration or in sodium dodecyl sulfate-polyacrylamide gel electrophoresis migration pattern. These studies indicate that while clonally selected strains of Neisseria gonorrhoeae undergo phenotypic variation at the epitope level, the impact of this variation on the total LOS of the population has little overall effect on its antigenic or physicochemical properties.

Antibodies, Monoclonal↗
PubMed1987

Physical heterogeneity of neisserial lipooligosaccharides reflects oligosaccharides that differ in apparent molecular weight, chemical composition, and antigenic expression.

We studied the oligosaccharides (OS) of outer membrane lipooligosaccharides (LOS) of Neisseria gonorrhoeae and Neisseria meningitidis. OS from the LOS of an individual neisserial strain always eluted from Sephadex G-50S as multiple peaks; the polyacrylamide gel elution profiles were nearly identical to the polyacrylamide gel electrophoresis profiles of the sodium dodecyl sulfate-disaggregated native LOS from which the OS were derived. Neisserial OS coeluted with Dex14 to Dex27 dextran oligomers (Mr, 2,210 to 4,320). Monosaccharide composition varied among the several OS released from the LOS of a single strain. The two OS of a gonococcal strain sensitive to normal human serum (NHS) bacteriolysis (sers) varied in their ability to inhibit the binding of NHS immunoglobulin M to their parental LOS. The OS that was rich in hexosamines inhibited NHS immune lysis of its parent strain; the OS that was poor in hexosamines did not. We conclude that structural differences in their OS account for the Mr heterogeneity of the LOS of a strain.

Acetates↗
PubMed1986

Bactericidal antibody response of normal human serum to the lipooligosaccharide of Neisseria gonorrhoeae.

Human antibody to lipooligosaccharide (LOS) from pooled normal human serum (NHS) and human immunne serum globulin (HISG) was isolated by affinity chromatography from a Sepharose column to which Escherichia coli strain J-5 LOS had been conjugated. Fractionated antibody was tested for bactericidal activity against serum-resistant Neisseria gonorrhoeae strains JW31, WR220, or 838 or serum-sensitive strains JW31R or 1074. By enzyme-linked immunosorbent assay the eluate of antibody to LOS contained IgM, IgA, and IgG antibodies to both JW31 and JW31R LOS. The IgM fraction from NHS was bactericidal at 30 min for strains JW31R and 1074 but failed to kill strains JW31 and 838. An IgG fraction from HISG was bactericidal for strains JW31 and WR220 yet failed to kill strain JW31R. The IgA fraction from NHS did not kill either strain JW31 or JW31R. Blocking experiments indicated that IgA or IgG failed to prevent IgM-mediated killing of strain JW31R, whereas IgA blocked the IgG-mediated killing of strain JW31.

Antibody Formation↗
PubMed1986

Antigenic and physical diversity of Neisseria gonorrhoeae lipooligosaccharides.

We used mouse monoclonal antibodies (MAbs) to characterize Neisseria gonorrhoeae lipooligosaccharide (LOS). LOSs that bound two or more MAbs in a solid-phase radioimmunoassay usually bound them to different LOS components, as separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE); strains with multiple LOS components on SDS-PAGE usually bound more than one MAb. However, the LOS of some strains bound the same MAb to two LOS components with different relative molecular weights, and some individual LOS components bound more than one MAb. LOSs from different strains bound different amounts of the same MAb at saturation, reflecting differences in the quantitative expression of individual LOS components. Not all components recognized by MAbs were stained by silver after periodate oxidation. Treatment with NaOH variously affected epitopes defined by different MAbs. MAb 3F11 completely inhibited and MAb 2-1-L8 partially inhibited the binding of 125I-labeled 06B4 MAb to WR220 LOS and WR220 outer membranes in competitive binding studies. Other MAbs did not compete with the binding of 125I-labeled 06B4 to either antigen. We conclude that a strain of N. gonorrhoeae elaborates multiple LOSs that can be separated by SDS-PAGE and that are antigenically distinct. Epitope expression within these glycolipids is complex.

Antibodies, Monoclonal↗
PubMed1986

Stability of expression of Neisseria gonorrhoeae lipooligosaccharides.

We compared multiple lipooligosaccharide (LOS) extracts from individual strains of Neisseria gonorrhoeae. Each of the extracts was prepared from single mass cultures grown on solid media under similar conditions but separated by time. We found only subtle variations in the number, electrophoretic mobility, and concentration of components of the LOSs from individual strains. We found no variation in the expression of a 3.6-kilodalton LOS component that carries the L8 LOS epitope. A significant variation in the 3-deoxy-D-manno-octulosonic acid content was found among different extracts from the same strain, but this variation appeared to be unrelated to the other LOS characteristics studied.

Antibodies, Monoclonal↗
PubMed1985

Elaboration of a 3.6-kilodalton lipooligosaccharide, antibody against which is absent from human sera, is associated with serum resistance of Neisseria gonorrhoeae.

Neisseria gonorrhoeae strains that resist lysis by normal human sera (NHS) do so, in part, because NHS contain immunoglobulin M (IgM) specific for lipooligosaccharide (LOS) antigens of serum-sensitive strains, but lack antibodies for LOS antigens that can serve as loci for immune lysis of serum-resistant (serr) strains. We used a monoclonal antibody (McAb), specific for an epitope within a 3.6-kilodalton (kDa) component of Neisseria meningitidis L8 LOS, that binds a 3.6-kDa gonococcal LOS component so that we could explore further serr gonococcal strains. The McAb bound to the LOS of 6 of 7 serr of strains but not to the LOS of 0 of 14 serum-sensitive and serum-intermediate gonococcal strains of diverse origin. We studied three serr strains further. Strain 7134 does not elaborate the 3.6-kDa LOS component and does not bind the McAb; strains WR220 and WR302 do elaborate the 3.6-kDa LOS component. The titer (log2) at which the McAb, diluted in NHS, lysed strain WR220 was 7.7; for WR302 it was 3.7, and for 7134 it was 0. Addition of McAb to NHS caused increased classical and alternative-pathway C3 deposition onto strain WR220, but only classical-pathway-activated C3 deposition onto strain WR302. The difference in lytic effectiveness of the McAb for the two strains, therefore, may result from differences in alternative-pathway augmentation of McAb-dependent classical-pathway activation on their surfaces. None of 40 randomly selected normal young adults had serum antibody that could compete with the McAb for binding to WR220 LOS in a solid-phase RIA. We conclude that the 3.6-kDa LOS component is commonly expressed by serr strains of N. gonorrhoeae and that antibody to it would be lytic if present in human serum, but that it is infrequently, if ever, present. As a result, strains elaborating this LOS are resistant to lysis by NHS.

Animals↗
PubMed1985

Risk of group A meningococcal disease: bacterial interference and cross-reactive bacteria among mucosal flora.

During outbreaks of group A meningococcal disease in Seattle, Wash., and Portland, Oreg., we studied the mucosal flora of the affected population and comparison groups to identify possible determinants of susceptibility and resistance to disease. Antimeningococcal immunoglobulin A can block the bactericidal activity of specific antibodies of other classes and has been associated with susceptibility in adults. We used immunoprecipitation and fluorescent-antibody techniques to detect mucosal microorganisms cross-reactive with group A meningococci that might have stimulated such antibodies. Cross-reactive strains of Bacillus pumilus and Streptococcus faecalis were found. Bacterial interference on mucosal surfaces has been shown to reduce susceptibility to other pathogens. With an agar overlay technique, we sought nasopharyngeal microorganisms that inhibited the growth of group A meningococci. Forty-five percent of subjects carried inhibitory strains representing at least nine different species. Inhibitory strains were less common (32%) in residents from "skid row" areas (see D.J. Bogue, Skid Row in American Cities, University of Chicago Press, for a comprehensive definition of these areas) than in a comparison group that did not experience meningococcal disease (61%), suggesting that their presence may be associated with resistance to acquisition of meningococci or to meningococcal disease.

Adult↗
PubMed1984

Immune response of infants and children to disseminated infections with Neisseria meningitidis.

Acute- and convalescent-phase sera from 34 children and 10 young adults were studied to determine if, at what age, and to which antigens of Neisseria meningitidis they respond during disseminated disease. Seven children older than two years of age who were infected with group C or Y strains developed significant increases in both binding and bactericidal antibody. Children infected with group B strains infrequently (eight [31%] of 26) had measurable increases in serum antibody to this capsular polysaccharide; response was meager when it did occur, was unrelated to age, and was considerably poorer than that of young adults, of whom 80% responded. Convalescent-phase sera from all children contained bactericidal antibody. Binding capacity for group B polysaccharide accounted for only 35% of the bactericidal activity in convalescent-phase sera of children infected with group B strains. Bactericidal antibody in the sera of children who did not respond to capsular polysaccharides was often to a lipooligosaccharide antigen.

Adult↗
PubMed1984

Heterogeneity of molecular size and antigenic expression within lipooligosaccharides of individual strains of Neisseria gonorrhoeae and Neisseria meningitidis.

We determined the Mr of neisserial lipooligosaccharides (LOS) by using discontinuous sodium dodecyl sulfate-polyacrylamide gel electrophoresis, minimal loading concentrations, and Salmonella isogenic rough mutant LOS as Mr standards. Salmonella LOS were resolved into three components. The migration distance of each component was linearly related to its theoretical Mr (r = 0.99). Neisserial LOS also contained multiple components whose calculated Mr ranged from 3,200 to 7,100. The relative abundance of components and their MrS varied greatly among strains. Meningococcal LOS were composed almost exclusively of two closely migrating components; gonococcal LOS were more heterogeneous. LOS from a gonococcus selected for resistance to a Pseudomonas pyocin contained only a single component that was different from and of intermediate Mr among the three components of the parent strain. A monoclonal antibody directed against the meningococcal L8 LOS epitope was used to determine whether heterogeneity of antigen expression reflected Mr heterogeneity. Single components of the L8 meningococcal LOS and of the LOS of 3 of 19 gonococcal strains bound the monoclonal antibody. Gonococcal LOS components that expressed the L8 epitope were of a similar Mr (4,800). Smaller components of these same LOS did not express the epitope.

Antibodies, Monoclonal↗
PubMed1984

Group A meningococcal disease in skid rows: epidemiology and implications for control.

Interviews conducted during outbreaks of group A meningococcal disease in skid row communities suggested that heavy alcohol use was associated with increased risk of disease. Frequent moving within skid row and from one skid row to another was characteristic of a subpopulation with increased risk of disease and may have facilitated spread within and between skid rows. The observations discussed herein have important implications for control of communicable diseases in and near skid rows.

Adult↗