Figure 6.

CM and AtM contribution to anti-Pf serum IgG. (A) Representative MS/MS spectra. Observed b-type fragment ions (containing the N terminus), y-type fragment ions (containing the C terminus), and loss of water (*) are indicated. Ions corresponding to the loss of water are labeled. Observed backbone cleavages are indicated (⌉ for b-type ions, ⌊ for y-type ions). Data shown are representative of at least three independent experiments on two different instruments. (B) IgH amino acid sequences of CM and AtM antibodies. Framework regions (FWR) and complementarity determining regions (CDR) are indicated. Blue stars indicate somatic point mutations. Mass spectrometric peptides with identical amino acid sequence are indicated in red. (C) RT-PCR amplicons of secretory and membrane IgG transcripts from the indicated B cell subpopulations. Data shown are representative of at least two independent experiments. (D) Serum IgG subclass distribution in donors from the Lambaréné area. (E) IgG subclass distribution as determined by IGH gene transcript sequence analysis. n indicates the number of tested sera. Error bars indicate SD.