High-Resolution Epitope Mapping and Affinity Binding Analysis Comparing a New Anti-Human LAG3 Rabbit Antibody Clone to the Commonly Used Mouse 17B4 Clone.

Lymphocyte activation gene 3 (LAG3) is a T cell inhibitory receptor that promotes tumor cell immune escape and is a potential target for cancer diagnostic and immunotherapeutic applications. We used automated capillary electrophoresis (ACE), surface plasmon resonance (SPR), and immunohistochemistry (IHC) to compare the binding characteristics of a new anti-LAG3 rabbit antibody clone, SP464, with the thirty-year old and extensively used anti-LAG3 mouse 17B4 clone. The rabbit SP464 clone exhibited between 20× to 30× greater binding to LAG3 than did the mouse 17B4 clone. Using these tools, we precisely mapped the relative locations of the epitopes of these two antibodies. The SP464 and 17B4 minimal epitopes were localized to separate, but overlapping, sub-fragments within the amino-terminal fifteen acids of the original thirty-mer peptide immunogen used to generate both antibodies. Application of this approach for quantifying the effects of alanine substitutions along the minimal SP464 epitope identified two amino acids essential for binding and four amino acids that likely contribute towards binding. Together, ACE, SPR, and IHC constitute a powerful orthologous approach for comparing antibody-binding characteristics and for fine mapping of linear epitopes within short immunogens. Our results indicate that the rabbit clone SP464 may be useful for assessing LAG3 expression.

Molecular phylogeny of Lichen Tiger Moths (Lepidoptera, Erebidae, Arctiinae, Lithosiini): a contribution toward classifying Western Hemisphere genera.

This study analyzes molecular sequence data from one mitochondrial (COI) and two nuclear (28S, RPS5) genes to test the monophyly of previously proposed subtribes of the Lithosiini (Erebidae: Arctidinae), including subtribal assignment of all North American genera that occur north of Mexico. After transferring Gardinia W.F. Kirby from Lithosiina to Cisthenina, there is strong support for a monophyletic Lithosiina, which includes three originally unplaced Nearctic genera: Agylla Walker, Inopsis Felder, and Gnamptonychia Hampson. The result of this study removes Clemensia Packard and Pronola Hampson from Cisthenina and places them in subtribe Clemensiina. We synonymize Eudesmiina under Cisthenina. After these changes, the phylogeny shows strong support for the monophyly of Cisthenina, which includes a further three unplaced Nearctic genera: Gardinia Kirby, Bruceia Neumögen, and Ptychoglene Felder. The monophyly of Cisthenina (including Eudesmia and Gardinia) is supported by two apomorphies found in adults: the apodemes of the second abdominal sternite are long and the anterolateral processes are fused with the rest of the sternite.

Immunohistochemistry with Anti-BRAF V600E (VE1) Mouse Monoclonal Antibody is a Sensitive Method for Detection of the BRAF V600E Mutation in Colon Cancer: Evaluation of 120 Cases with and without KRAS Mutation and Literature Review.

The major aim of this study was to evaluate the performance of anti-BRAF V600E (VE1) antibody in colorectal tumors with and without KRAS mutation. KRAS and BRAF are two major oncogenic drivers of colorectal cancer (CRC) that have been frequently described as mutually exclusive, thus the BRAF V600E mutation is not expected to be present in the cases with KRAS mutation. In addition, a review of 25 studies comparing immunohistochemistry (IHC) using the anti-BRAF V600E (VE1) antibody with BRAF V600E molecular testing in 4041 patient samples was included. One-hundred and twenty cases with/without KRAS or BRAF mutations were acquired. The tissue were immunostained with anti-BRAF V600E (VE1) antibody with OptiView DAB IHC detection kit. The KRAS mutated cases with equivocal immunostaining were further evaluated by Sanger sequencing for BRAF V600E mutation. Thirty cases with BRAF V600E mutation showed unequivocal, diffuse, uniform, positive cytoplasmic staining and 30 cases with wild-type KRAS and BRAF showed negative staining with anti-BRAF V600E (VE1) antibody. Out of 60 cases with KRAS mutation, 56 cases (93.3%) were negative for BRAF V600E mutation by IHC. Four cases showed weak, equivocal, heterogeneous, cytoplasmic staining along with nuclear staining in 25-90% of tumor cells. These cases were confirmed to be negative for BRAF V600E mutation by Sanger sequencing. Overall, IHC with anti-BRAF V600E (VE1) antibody using recommended protocol with OptiView detection is optimal for detection of BRAF V600E mutation in CRC. Our data are consistent with previous reports indicating that KRAS and BRAF V600E mutation are mutually exclusive.

A new species of Hypoprepia from the mountains of central Arizona (Lepidoptera, Erebidae, Arctiinae, Lithosiini).

A new firefly-mimicking lichen moth of the genus Hypoprepia, H.lampyroides Palting & Ferguson, sp. n., is described from the mountains of east-central Arizona and the Sierra Madre Occidental of Mexico. Hypoprepia Hübner, 1831 is a North American genus of lithosiine tiger moths, previously consisting of five species: H.fucosa Hübner, 1831 and H.miniata (Kirby, 1837), both of eastern and central North America; H.cadaverosa Strecker, 1878 from the Rocky Mountains into New Mexico and west Texas; H.inculta H. Edwards, 1882, a widespread western USA species and H.muelleri Dyar, 1907 from the vicinity of Mexico City. The latter is herein synonymized under H.inculta (= H.muelleri syn. n.), resulting in the total number of taxa in the genus unchanged at five.

Immunohistochemistry with the anti-BRAF V600E (VE1) antibody: impact of pre-analytical conditions and concordance with DNA sequencing in colorectal and papillary thyroid carcinoma.

The most common of all activating BRAF mutations (T1799A) leads to a substitution of valine (V) to glutamic acid (E) at the position 600 of the amino acid sequence. The major goal of this study was to compare detection of the BRAF V600E mutation by DNA sequencing with immunohistochemistry (IHC) using the anti-BRAF V600E (VE1) antibody. Archival formalin fixed, paraffin embedded tissues from 352 patients with colon adenocarcinoma (n = 279) and papillary thyroid carcinoma (n = 73) were evaluated for the BRAF V600E mutation by sequencing and IHC. The discordant cases were re-evaluated by repeat IHC, SNaPshot and next-generation sequencing (NGS). Furthermore, the effect of pre-analytical variables on the utility of this antibody was evaluated in two xenograft mouse models.After resolving 15 initially discordant cases, 212 cases were negative for the BRAF V600E mutation by IHC. Of these, 210 cases (99.1%) were also negative by sequencing and two cases (0.9%) remained discordant. Of the 140 cases that were IHC positive for BRAF V600E, 138 cases were confirmed by sequencing (98.6%) and two cases remained discordant (1.4%). Overall, the negative predictive value was 99.1%, positive predictive value 98.6%, sensitivity 98.6%, specificity 99.1% and overall percentage agreement 98.9% (348/352 cases). Tissue fixation studies indicated that tissues should be fixed for 12-24 h within 2 h of tissue collection with 10% neutral buffered formalin.