Binding of four LOS-specific IgG preparations (6940, 35E, 1291, and 8532V) to group B N. meningitidis strains 7946, 7994, and 7993 as determined by flow cytometry. The open curves indicate the binding of the secondary antibody alone, and the solid curves indicate the binding of IgG. N. gonorrhoeae does not have designated L types, but strain 1291 expresses LNnT paraglobosyl LOS that is identical to that of the L7 LOS made by meningococci.