Table 3.

Cumultative data on IgA1 protease-producing bacteria and homologous IgA1 protease-inhibiting activity in samples (obtained by method 3) of nasal wash from six adults and a child

Subject and sampleaIgA1 protease-producing bacteriaIgA1 protease-inhibiting activity
OrganismEstimated density in undiluted secretion (CFU ml−1)b% of total floraIgA1 protease activity in vitro (C50)cIn nasal wash (CI50 titer)Relative to total Ig conc (CI50titer μg−1 ml)Estimated for undiluted secretion (CI50 titer)d
A3,1S. pneumoniae2.1 × 1030.2410 (275–5,066)4.20.1897.5
B3,1S. mitis biovar 16.8 × 10422.31,621 (5.2–2,093)0.000
C3,1H. influenzae7.2 × 10699.64,760 (52–12,830)8.60.22199
D3,1H. influenzae<1.5 × 104<0.01639 (52–12,830)18.20.16422
E3,1S. mitis biovar 10e01,519 (5.2–2,093)0.000
G3,3H. influenzae>3 × 106 NDf2,029 (52–12,830)51.01.261,183
Iw,3H. influenzae>3 × 106ND5,120 (52–12,830)10.41.58241
  • a Designations are as in Table 2.

  • b Calculated as CFU per milliliter of wash × 23.2 because individual dilution factors for these samples were not available.

  • c C50 titer of a stationary-phase liquid culture (range of previously recorded [40] C50 titers for strains of the species).

  • d Calculated as CI50 for nasal wash × 23.2.

  • e IgA1 protease-producing S. mitisbiovar 1 was not detected in nasal wash but constituted 0.6% of the CFU in a swab corresponding to a filter paper sample.

  • f ND, not determined.