Targeting Topics 13q1

Role for kisspeptin/neurokinin B/dynorphin (KNDy) neurons in cutaneous vasodilatation and the estrogen modulation of body temperature.

Mittelman-Smith MA, Williams H, Krajewski-Hall SJ, McMullen NT, Rance NE.

Proc Natl Acad Sci U S A 109(48):19846-19851, 2012.

Menopause is marked by estrogen withdrawal, and also by hot flushes. Given the fact that hypothalamic levels of kisspeptin/neurokinin B/dynorphin (KNDy) neurons are significantly altered in menopause, the authors investigated whether these neurons are involved in the generation of flushes. Rats received bilateral injections of NK3-SAP (Cat. #IT-63) into the arcuate nucleus – a total of 40 ng. Blank-SAP (Cat. #IT-21) was used as control. The data indicate that KNDy neurons promote cutaneous vasodilation, and play a role in 17β-estradiol modulation of body temperature, supporting the hypothesis that these neurons could play a role in the generation of hot flushes.

CD22 Antigen Is Broadly Expressed on Lung Cancer Cells and Is a Target for Antibody-Based Therapy.

Tuscano JM, Kato J, Pearson D, Xiong C, Newell L, Ma Y, Gandara DR, O’Donnell RT.

Cancer Res 72(21):5556-5565, 2012.

The median overall survival of patients with advanced, unresectable, non-small cell lung cancer is 9-12 mos. A potential therapeutic target is CD22, a protein expressed on lung cancer cells. The authors examined the use of the monoclonal antibody HB22.7 as an antitumor agent. To assess internalization of the antibody, it was first incubated with 10 μg/ml Mab-ZAP (Cat. #IT-04) then applied to two different cancer cell lines in culture. Analysis of cell viability demonstrated that CD22 internalized when bound by the antibody-toxin complex, suggesting that targeting CD22 has therapeutic potential.

Histamine release in the basal forebrain mediates cortical activation through cholinergic neurons.

Zant JC, Rozov S, Wigren HK, Panula P, Porkka-Heiskanen T.

J Neurosci 32(38):13244-13254, 2012.

The basal forebrain modulates many functions, among them the regulation of wakefulness and cortical arousal. Previous data has linked increases in histaminergic transmission to increases in wakefulness. In order to further investigate various facets of this system, the authors injected 230 ng of 192-IgG-SAP (Cat. #IT-01) into the horizontal diagonal band of Broca/substantia innominata/magnocellular preoptic area of rats. While control animals displayed several changes on administration of exogenous histamine, the lesioned animals had none of these changes.

Acetylcholine facilitates recovery of episodic memory after brain damage.

Croxson PL, Browning PG, Gaffan D, Baxter MG.

J Neurosci 32(40):13787-13795, 2012.

Episodic memory is controlled by several interconnected brain structures. The order in which these structures sustain damage can affect the processes lost. In this work the authors performed numerous bilateral injections of ME20.4-SAP (Cat. #IT-15) into the infero-temporal cortex, the medial surface of the temporal lobe, the perirhinal and entorhinal cortex, and the temporal pole of monkeys. These injections totaled 2.2-2.5 μg of conjugate. The results indicate that loss of cortical acetylcholine function will interfere with adaptation to memory impairments caused by structural damage in episodic memory centers.

Form and function of the M4 cell, an intrinsically photosensitive retinal ganglion cell type contributing to geniculocortical vision.

Estevez ME, Fogerson PM, Ilardi MC, Borghuis BG, Chan E, Weng S, Auferkorte ON, Demb JB, Berson DM.

J Neurosci 32(39):13608-13620, 2012.

Intrinsically photosensitive retinal ganglion cells (ipRGCs) are cells that contain the photopigment melanopsin. In this work the authors extensively characterize the M4 ipRGCs. A melanopsin antibody (Cat. #AB-N38) at a 1:10,000 dilution was used to determine the presence of melanopsin by immunohistochemistry.

Diffusion-weighted magnetic resonance imaging detection of basal forebrain cholinergic degeneration in a mouse model.

Kerbler GM, Hamlin AS, Pannek K, Kurniawan ND, Keller MD, Rose SE, Coulson EJ.

Neuroimage 66C:133-141, 2012.

The authors examined the effectiveness of diffusion MRI using diffusion tensor imaging (DTI) and probabilistic tractography in detecting cholinergic loss in a mouse model. Mice received bilateral 0.2-μg icv injections of mu p75-SAP (Cat. #IT-16). Rabbit IgG-SAP (Cat. #IT-35) was used as control. The animals were then examined using DTI. The data indicate that DTI is a valid technique for assessment of cholinergic loss in septo-hippocampal tracts as a result of Alzheimer’s disease.

Photochemical internalization (PCI) of HER2-targeted toxins: Synergy is dependent on the treatment sequence.

Berstad MB, Weyergang A, Berg K.

Biochim Biophys Acta 1820(12):1849-1858, 2012.

A majority of patients develop acquired resistance to trastuzumab, the monoclonal antibody recognizing HER2, coupled to a toxin as a breast cancer therapeutic. One of the modes of resistance is that the therapeutic molecule is trapped inside an endocytic vesicle. PCI is a technique that facilitates cytosolic release of molecules in vesicles. The authors investigated the potency of biotinylated trastuzumab combined with streptavidin-ZAP (Cat. #IT-27) on several cell lines.

The effect of the steroid sulfatase inhibitor (p-O-sulfamoyl)-tetradecanoyl tyramine (DU-14) on learning and memory in rats with selective lesion of septal-hippocampal cholinergic tract.

Babalola PA, Fitz NF, Gibbs RB, Flaherty PT, Li PK, Johnson DA.

Neurobiol Learn Mem 98(3):303-310, 2012.

Steroid sulfatase inhibitors such as dehydroepiandrosterone (DHEAS) have memory-enhancing effects. Working with both DHEAS and the steroid sulfatase inhibitor DU-14, the authors examined cholinergic function by infusing 0.2 μg of 192-IgG-SAP (Cat. #IT-01) into the medial septum of rats. The results indicate that memory associated with contextual fear is facilitated by steroid sulfatase inhibition, but acquisition of spatial memory is impaired by these same lesions.

Cholinergic degeneration is associated with increased plaque deposition and cognitive impairment in APPswe/PS1dE9 mice.

Laursen B, Mork A, Plath N, Kristiansen U, Bastlund JF.

Behav Brain Res 240:146-152, 2013.

Extracellular plaques containing amyloid β-peptides (Aβ) and cholinergic dysfunction are two of the main hallmarks of Alzheimer’s disease. Using a transgenic mouse line that displays an age-related increase in plaque deposition, the authors examined the relationship between cholinergic degeneration and Aβ overexpresssion. Mice received 0.9-μg bilateral icv injections of mu p75-SAP (Cat. #IT-16). Working memory was significantly impaired in lesioned mice with plaques, and the plaque burden was increased as compared to wild-type mice that also received a lesion.

IB4(+) nociceptors mediate persistent muscle pain induced by GDNF.

Alvarez P, Chen X, Bogen O, Green PG, Levine JD.

J Neurophysiol 108(9):2545-2553, 2012.

GDNF is found in skeletal muscle and can trigger mechanical hyperalgesia. The authors administered a 3.2-μg intrathecal dose of IB4-SAP (Cat. #IT-10) to rats. Loss of the IB4(+) nociceptors led to decreased hyperalgesic priming as well as a reduction in GDNF-induced hyperalgesia. These data indicate that GDNF plays a role in mediating induction of pain.

Efficacy of a CD22-targeted antibody-saporin conjugate in a xenograft model of precursor-B cell acute lymphoblastic leukemia.

Kato J, Satake N, O’Donnell RT, Abuhay M, Lewis C, Tuscano JM.

Leuk Res 37(1):83-88, 2013.

Most cases of acute lymphoblastic leukemia (ALL) are of B-cell lineage. Although children with ALL have a high survival rate, there is a subset of children with a much lower survival rate, and long-term side effects from treatment are problematic. CD22 has been suggested as a therapeutic target because it is not present on hematopoietic stem cells, therefore allowing regeneration of normal B cells following depletion of malignant B cells. The authors used a custom conjugate of the antibody HB22.7 and saporin to demonstrate specific toxicity against pre-B ALL cell lines. Mouse IgG-SAP (Cat. #IT-18) was used as a control.

Insights into the mechanism of cell death induced by saporin delivered into cancer cells by an antibody fusion protein targeting the transferrin receptor 1.

Daniels-Wells TR, Helguera G, Rodriguez JA, Leoh LS, Erb MA, Diamante G, Casero D, Pellegrini M, Martinez-Maza O, Penichet ML.

Toxicol In Vitro 27(1):220-231, 2013.

The antibody-avidin fusion protein ch128.1Av has been shown to target the human transferrin receptor 1 (TfR1) and kill malignant B cells by blocking the use of iron. Combination of this construct with a mono-biotinylated saporin custom conjugate produces an iron-independent toxicity to TfR1-expressing cells, even those that are resistant to ch128.1Av alone. The saporin-containing conjugate induces a transcriptional response consistent with oxidative stress and DNA damage. The data also show that the saporin conjugate is not toxic to human hematopoeietic stem cells.

Identification and characterization of a sleep-active cell group in the rostral medullary brainstem.

Anaclet C, Lin JS, Vetrivelan R, Krenzer M, Vong L, Fuller PM, Lu J.

J Neurosci 32(50):17970-17976, 2012.

The authors attempt to locate and identify specific neuronal populations that promote sleep. One method utilized was 130-330 pg injections of orexin-SAP (Cat. #IT-20) into the parafacial zone. These results establish the parafacial zone as a delimited node of sleep-active neurons.

Metabolic effects of chronic sleep restriction in rats.

Vetrivelan R, Fuller PM, Yokota S, Lu J, Saper CB.

Sleep 35(11):1511-1520, 2012.

In order to investigate whether there is a correlation between sleep and weight the authors administered 200 nl of a 0.1% solution of orexin-SAP (Cat. #IT-20) to the ventrolateral preoptic area of rats. Although the lesioned animals slept less than the controls, weight gain was slower than controls.