Figure 4.

Isoelectric point (pI) of various antigens and κ to λ light chain (κ/λ) ratio. Isoelectric points of various antigens were calculated (available at: http://web.expasy.org/compute_pi/) on the basis of published sequences and compared with mean κ/λ ratios for each antigen. Antigens include tetanus toxoid (pI 5.79) and HIV antigens p24 (pI 6.26), p66 (pI 8.57), p51 (pI 8.64), pr55 (pI 9.17), gp41 (pI 8.92), gp160 (pI 8.96)0, gp120 (pI 9.19), vif (pI 9.89), and p7 (pI 10.08).There was a correlation between the pI of antigen and the κ/λ ratio (a higher pI was associated with a lower κ/λ ratio; P = .004; r² = .71).