Passive immunization of the human vagina

Figures & data

Figure 1. (a) FcRn (IgG transport molecule) expression by basal epithelial cells in the human vaginal epithelium, as visualized by immunohistology. FcRn-positive cells appear purple. (b) IgG uptake by apical epithelial cells in the stratum corneum of the human vaginal epithelium. Cy3-labeled (red) IgG, which had been added to the apical surface of vaginal tissue, was visualized by fluorescence microscopy in the apical cells.

Table 1. MAb pharmacokinetic data from the MB66 trial.

	Cervical Os			Ectocervix			Mid vagina			Distal vagina
Time point	Median*	Min	Max	Median	Min	Max	Median	Min	Max	Median	Min	Max
Baseline	<1.6	<1.6	<1.6	<1.6	<1.6	<1.6	<1.6	<1.6	<1.6	<1.6	<1.6	<1.6
1 hr Post Film	846.9	73.4	4911.3	748.8	131.4	6768.3	1008.0	15.3	3174.2	31.3	1.6	1480.0
4 hrs Post Film	630.8	1.6	3788.9	541.4	112.1	3185.7	387.4	71.4	2622.0	168.1	1.6	8548.5
24 hr Post Film	18.6	1.6	128.2	27.1	1.6	162.3	88.0	5.0	746.9	52.8	1.6	509.2

*µg/mL; corrected for dilution factor (1:20)

Fifteen women received a vaginal film containing 10 mg of VRC01 and 10 mg of HSV8 monoclonal antibodies; four vaginal sites [cervical os, ectocervix, midvagina and distal vagina (vaginal opening)] were sampled by tear-flo wicks 1 hr, 4 hrs and 24 hrs post film insertion. VRC01 antibody concentrations in vaginal fluid over time are shown in this table. All 4 vaginal sites had significantly elevated antibody concentrations at 1 hr, 4 hrs and 24 hrs following insertion of film compared to baseline (p < 0.0001 for all except 24hr cervical os which was p < 0.01).