Figure 3.

Immunoglobulin class and subclass specificity of the anti-Chlamydia antibody response. Serum samples collected from individual mice (6 per group) infected with Chlamydia trachomatis serovar A (), D (), or L2 (□) or with Chlamydia muridarum (▪) were tested for anti-Chlamydia antibody using the homologous infecting Chlamydia strain as antigen in the enzyme-linked immunosorbent assay (eg, serum from serovar A–infected mice was tested against serovar A EBs). Data are presented as the mean anti-Chlamydia titer ± standard error of the mean for the indicated class and subclass immunoglobulins of serum collected 28 days after primary infection (A), 42 days after primary infection (B), 23 days after secondary challenge (C), and 29 days after tertiary challenge (D). Ig, immunoglobulin.