Targeting Topics 15q2

Cortically projecting basal forebrain parvalbumin neurons regulate cortical gamma band oscillations.

Kim T, Thankachan S, McKenna JT, McNally JM, Yang C, Choi JH, Chen L, Kocsis B, Deisseroth K, Strecker RE, Basheer R, Brown RE, McCarley RW.

Proc Natl Acad Sci U S A 112(11):3535-3540, 2015.

Measurements of cortical EEG capture gamma band oscillations (GBO). Abnormalities in these GBO have been found in some neuropsychiatric disorders such as Alzheimer’s disease and schizophrenia. The authors analyzed GBO neuronal groups by administering 650-ng bilateral icv injections of mu p75-SAP (Cat. #IT-16) to mice to determine the role of basal forebrain cholinergic neurons in the generation of GBO. The results indicate GABAergic basal forebrain neurons containing parvalbumin were important for GBO integrity, but cholinergic neurons in the basal forebrain were not involved.

alphaCGRP is essential for algesic exocytotic mobilization of TRPV1 channels in peptidergic nociceptors.

Devesa I, Ferrandiz-Huertas C, Mathivanan S, Wolf C, Lujan R, Changeux JP, Ferrer-Montiel A.

Proc Natl Acad Sci U S A 111(51):18345-18350, 2014.

The sensitization of transient receptor potential vanilloid 1 (TRPV1) can lead to the development and maintenance of chronic pathological pain conditions. In this work the authors determined that TRPV1 receptors use membrane insertion mechanisms in order to potentiate neuronal excitability. In order to specifically link this activity to peptidergic neurons the authors treated rat primary dorsal root ganglion cultures with 10 mM rIB4-SAP (Cat. #IT-10) to deplete the non-peptidergic neurons.

Monoclonal Antibodies Targeting LecLex-Related Glycans with Potent Antitumor Activity.

Chua JX, Vankemmelbeke M, McIntosh RS, Clarke PA, Moss R, Parsons T, Spendlove I, Zaitoun AM, Madhusudan S, Durrant LG.

Clin Cancer Res 21(13):2963-2974, 2015.

In this work the authors characterized two monoclonal antibodies that target glycans containing Lewis carbohydrate antigens. One of the methods used was to combine varying concentrations of the antibodies with 50 ng mouse Fab-ZAP (Cat. #IT-48) and apply the conjugates to cells for 72 hours. The antibodies were demonstrated to have efficient internalization, supported by potent in vivo anti-tumor activity.

Light-controlled endosomal escape of the novel CD133-targeting immunotoxin AC133-saporin by photochemical internalization – A minimally invasive cancer stem cell-targeting strategy.

Bostad M, Olsen CE, Peng Q, Berg K, Hogset A, Selbo PK.

J Control Release 206:37-48, 2015.

Previously the authors demonstrated the use of photochemical internalization of a custom conjugate consisting of a CD133 antibody coupled to saporin (ATS Custom conjugation). Several cancer cell lines were plated, and incubated in the presence of a photosensitizer with either CD133-SAP at 8.6 pM or Saporin (Cat. #PR-01) at 24 pM. The different concentrations equalized the number of saporin molecules in each sample. A light source was used to initiate the internalization of the molecules. The results indicate that this is a viable strategy for the targeted treatment of cancer stem cells.

High-content analysis of antibody phage-display library selection outputs identifies tumor selective macropinocytosis-dependent rapidly internalizing antibodies.

Ha KD, Bidlingmaier SM, Zhang Y, Su Y, Liu B.

Mol Cell Proteomics 13(12):3320-3331, 2014.

Macropinocytosis, the internalization of large endocytic vesicles called macropinosomes, is upregulated in Ras-transformed cancers. To date, large-scale antibody generation strategies have not incorporated a selection method for antibodies. In this work the authors demonstrate screening and validation of the antibodies that utilize the macropinosome pathway. One method used was to biotinylate the antibodies and combine them with Streptavidin-ZAP (Cat. #IT-27) at a 1:1 ratio. The conjugate was applied to cells in a concentration curve starting at 200 nM in order to demonstrate internalization and cell killing.

T-box transcription regulator Tbr2 is essential for the formation and maintenance of Opn4/melanopsin-expressing intrinsically photosensitive retinal ganglion cells.

Mao CA, Li H, Zhang Z, Kiyama T, Panda S, Hattar S, Ribelayga CP, Mills SL, Wang SW.

J Neurosci 34(39):13083-13095, 2014.

Opsin 4/melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs) are responsible for controlling non-image-forming visual functions in the retina. The findings show that opsin 4 is only expressed in Tbr2-positive ipRGCs, no ipRGCs are found if Tbr2 is deleted before RGC specialization, and most ipRGCs are eliminated when Tbr2 is deleted from established ipRGCs. An antibody against melanopsin (Cat. #AB-N39) was used at a 1:1000 dilution for immunohistochemical analyses.

TrkA in vivo function is negatively regulated by ubiquitination.

Kiris E, Wang T, Yanpallewar S, Dorsey SG, Becker J, Bavari S, Palko ME, Coppola V, Tessarollo L.

J Neurosci 34(11):4090-4098, 2014.

The high affinity nerve growth factor receptor, trkA, plays an intrinsic role in the regulation of various aspects of the mammalian nervous system. The post-translational attachment of ubiquitin to trkA plays a role in the final disposition and function of many proteins; in this work the authors investigate the result of trkA ubiquitination. By removing a 3 amino acid sequence from the receptor the ubiquitination of TrkA was reduced which resulted in an increase in TrkA protein levels and activity. In mice containing this mutation, the rise in TrkA activity was accompanied by enhanced thermal sensitivity and inflammatory pain. Anti-trkA (Cat. #AB-N03) was used at a concentration of 1:500 in immunohistochemistry.

Characteristic patterns of dendritic remodeling in early-stage glaucoma: evidence from genetically identified retinal ganglion cell types.

El-Danaf RN, Huberman AD.

J Neurosci 35(6):2329-2343, 2015.

The loss of retinal ganglion cells (RGC) is the second-most common cause of blindness worldwide. Using several mouse transgenic cell lines, the authors investigated the changes that occur on the establishment of elevated ocular pressure. Anti-melanopsin (Cat. #AB-N39) at 1:1000 was used to illuminate the morphology of the M1 intrinsically photosensitive RGC.

Individual Differences in Acute Pain-induced Endogenous Analgesia Predict Time to Resolution of Postoperative Pain in the Rat.

Peters CM, Hayashida K, Suto T, Houle TT, Aschenbrenner CA, Martin TJ, Eisenach JC.

Anesthesiology 122(4):895-907, 2015.

The authors investigated the relationship between preoperative Conditioned Pain Modulation (CPM) and the time course of recovery from surgery. CPM was evaluated using forepaw capsaicin injections into rats. During the study, lesioned rats received 5-μg intrathecal injections of anti-DBH-SAP (Cat. #IT-03), followed 14 days later by a partial L5 spinal nerve ligation surgery. Mouse-IgG-SAP (Cat. #IT-18) was used as a control. CPM was partially blocked in the lesioned animals, suggesting descending noradrenergic signaling is important in the time course of recovery from surgery.

New mouse retinal stroke model reveals direction-selective circuit damage linked to permanent optokinetic response loss.

Joly S, Guzik-Kornacka A, Schwab ME, Pernet V.

Invest Ophthalmol Vis Sci 55(7):4476-4489, 2014.

The authors used a mouse model of ‘retinal stroke’ to better delineate the optokinetic response deficits at the cellular level. Damage was found in the processes of starburst amacrine cells (SACs), and to a lesser extent, the dendrites. Anti-melanopsin (Cat. #AB-N38) at 1:2500 was used for immunohistochemistry.

Neutral aminoaciduria in cystathionine beta-synthase-deficient mice; an animal model of homocystinuria.

Akahoshi N, Kamata S, Kubota M, Hishiki T, Nagahata Y, Matsuura T, Yamazaki C, Yoshida Y, Yamada H, Ishizaki Y, Suematsu M, Kasahara T, Ishii I.

Am J Physiol Renal Physiol 306(12):F1462-76, 2014.

The authors utilized a mouse model for homocystinuria in order to examine renal amino acid reabsorbtion. Some of the immunohistochemistry experiments used anti-Met (Cat. #AB-T036). It was found that loss of cystathionine β-synthase causes hyperexcretion of both glucogenic and ketogenic neutral amino acids, as well as histidine.

TRPV1 expression level in isolectin B4-positive neurons contributes to mouse strain difference in cutaneous thermal nociceptive sensitivity.

Ono K, Ye Y, Viet CT, Dang D, Schmidt BL.

J Neurophysiol 113(9):3345-3355, 2015.

In order to determine whether IB4-positive trigeminal sensory neurons affect pain sensitivity, the authors administered 2 μg of rIB4-SAP (Cat. #IT-10) to the right infraorbital foramen. Saporin (Cat. #PR-01) was used as a control.

Macrophages are needed in the progression of tuberculosis into lung cancer.

Li J, Pan Y, Zhang B, Chen Q.

Tumour Biol 36(8):6063-6066, 2015.

Approximately 30% of lung carcinomas also have tuberculosis lesions. The authors investigated the potential link between inflammatory processes and cancer in the lung. Mice with established tuberculosis infections received weekly 20 μg tail vein injections of Mac-1-SAP (Cat. #IT-06) in order to eliminate macrophages. Six months later the mice receiving Mac-1-SAP had a significantly lower incidence of lung carcinoma than control animals.

Dual targeting NG2 and GD3A using Mab-Zap immunotoxin results in reduced glioma cell viability in vitro.

Higgins SC, Fillmore HL, Ashkan K, Butt AM, Pilkington GJ.

Anticancer Res 35(1):77-84, 2015.

Human glioma-derived cell lines were sequentially incubated with anti-NG2 and anti-GD3A coupled to Mab-ZAP (Cat. #IT-04) at 1 μg/ml and 5 μg/ml for 72 hours each. The combination therapy was significantly more effective than single therapy in eliminating the glioma cells.

Activation of the mouse primary visual cortex by medial prefrontal subregion stimulation is not mediated by cholinergic basalo-cortical projections.

Nguyen HN, Huppe-Gourgues F, Vaucher E.

Front Syst Neurosci 9:1, 2015.

Mice received 1 μg icv injections of mu p75-SAP (Cat. #IT-16) to eliminate NGFr-positive cells. The results indicate a link between the prelimbic and infralimbic cortices and the primary visual cortex.

Preliminary results from a phase I study of substance P-saporin in terminal cancer patients with intractable pain.

Frankel AE, Nymeyer H, Lappi DA, Higgins D, Ahn C, Noe C.

J Clin Oncol 32 (suppl 31):191, 2014.

Existing pain therapies are insufficient to control cancer pain in 10-15% of patients. Substance P (SP) and its receptor, neurokinin-1 (NK-1r) have been determined to play a major role in spinal transmission of chronic pain. Animal studies have demonstrated that disruption of the NK-1r pathway alleviates chronic pain caused by a variety of stimuli. The authors are conducting a Phase I clinical trial in humans (NCT02036281) assessing the ability of SP-SAP (Cat. #IT-07) to treat intractable chronic pain due to cancer. Patients have received intrathecal injections of 1, 2, or 4 µg of SP-SAP with no evidence of toxicity or neurological or cardiac abnormalities. Doses will escalate up to 90 µg.