Diagnostic and Therapeutic Evaluation of an Anti-Langerhans Cell Histiocytosis Monoclonal Antibody (NA1/34) in a New Xenograft Model  Samuel Murray, Jenny F. Morris, Anthony C. Chu  Journal of Investigative Dermatology  Volume 114, Issue 1, Pages 127-134 (January 2000) DOI: 10.1046/j.1523-1747.2000.00831.x Copyright © 2000 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 1 FACS analysis. (a) Flow cytometric analysis of relative CD1a expression levels for HeLa (row A) and YC1H (row B) cells. Column 1 represents count versus FL1 log (fluorescence intensity) for control second layer FITC-F(ab′)2 anti-IgG. Column 2 represents anti-DNP binding and column 3 represents anti-CD1a binding of MoAb NA1/34. (b) Ex vivo CD1a expression. Flow cytometric analysis of single cell YC1H xenograft CD1a expression as demonstrated using NA1/34 (row B) compared with CD1a-negative control HeLa xenografts (row A). Journal of Investigative Dermatology 2000 114, 127-134DOI: (10.1046/j.1523-1747.2000.00831.x) Copyright © 2000 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 2 Xenograft/tissue ratios comparing 111In-DTPA-NA1/34 with 111In-DTPA-F(ab′)2 in YC1H xenograft bearing mice. Ratios represent %id per g of tissue compared with the xenograft uptake for the time points 5, 24, 48, and 120 h p.i. (mean ± SD). Intact MoAb NA1/34 represented by clear columns and F(ab′)2 by hashed columns. Tissue shown include bone (Bo), liver (Li), kidneys (Ki), lungs (Lu), spleen (Sp), intestine (In), and muscle (Mu). Journal of Investigative Dermatology 2000 114, 127-134DOI: (10.1046/j.1523-1747.2000.00831.x) Copyright © 2000 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 3 Intact and F(ab′)2 xenograft/blood ratios. Ratios for xenograft to blood are calculated for each time point postinjection comparing the intact 111In-DTPA-labeled-NA1/34 to the 111In-DTPA-labeled-F(ab′)2 NA1/34 fragments, values represent the mean ± SD. Journal of Investigative Dermatology 2000 114, 127-134DOI: (10.1046/j.1523-1747.2000.00831.x) Copyright © 2000 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 4 Cell cytotoxicity. (a) Percentage survival versus time for CD1a-negative HeLa cells (○) compared with CD1a-positive YC1H cells (•) receiving either Unlabeled NA1/34, 131I-labeled anti-DNP or 131I-labeled NA1/34. Results are plotted as mean ± SD with respect to total cell number as a factor of LDH levels. (b) LDH release. Percentage survival versus time for YC1H cells receiving doses of 131I-labeled NA1/34, 0.22 μCi, 2.2 μCi, and 11.1 μCi. Results are plotted as mean ± SD. Journal of Investigative Dermatology 2000 114, 127-134DOI: (10.1046/j.1523-1747.2000.00831.x) Copyright © 2000 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 5 Plot of relative xenograft growth rates. Relative xenograft volumetric means for the treatment groups receiving no treatment (n = 20) (⋄); 350 μCi 131I-labeled intact NA1/34 (n = 5) (▴); and 500 μCi 131I-labeled intact NA1/34 (n = 5) (▪); unlabeled NA1/34 (n = 6) (•) and 500 μCi 131I-labeled intact anti-DNP (n = 5) (♦). Treatment was given at day 0, relative xenograft volume was defined as 1 at time of treatment. Data points are plotted as the mean average of each group until the day at which the mean volume exceeded 3 (disease progression). Journal of Investigative Dermatology 2000 114, 127-134DOI: (10.1046/j.1523-1747.2000.00831.x) Copyright © 2000 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 6 Kaplan–Meier plot of xenograft survival. Percentage survival within each of the five treatment groups: no treatment (n = 20) (♦); 350 μCi 131I-labeled intact NA1/34 (n = 5) (▴); and 500 μCi 131I-labeled intact NA1/34 (n = 5) (○); unlabeled NA1/34 (n = 6) (•) and 500 μCi 131I-labeled intact anti-DNP (n = 5) (▪). Death was calculated as a 300% increase in xenograft volume as compared with volume at time of treatment (day 0). Journal of Investigative Dermatology 2000 114, 127-134DOI: (10.1046/j.1523-1747.2000.00831.x) Copyright © 2000 The Society for Investigative Dermatology, Inc Terms and Conditions