targeted-toxins

Q: I ordered a targeted toxin. Will it come in powder form? How do I re-dissolve it?

A: Our Saporin conjugate products are all provided in sterile PBS solution within a concentration range of 0.5 – 3 mg/ml. Saporin is an extremely safe ‘toxin’ to handle in standard laboratory environments when in solution for several reasons. Solutions in general are easier to corral and keep contained than powders and consequently are less likely to accidentally end up on an individual’s skin, tongue, or in one’s eyes. As a lyophilized product, Saporin would also be present at an extremely high concentration such that there is cause for concern should it contact the body of the user in any way. Lastly, our Saporin conjugates have historically required dilution prior to use for both in vitro and in vivo procedures. As such, it is much easier to ensure the amount of material you, as a customer, are receiving and the subsequent dilution is accurately adjusted to your desired concentration when providing these products already in solution. If upon receiving a Saporin conjugate you believe the product to be lyophilized or in a powder form, please contact us immediately, prior to opening the vial.

Related Products: Targeted Toxins

Wu Y, Song S, Liu H, Xing D, Wang X, Fei Y, Li G, Zhang C, Li Y, Zhang L (2015) Role of adrenomedullin in the cerebrospinal fluid-contacting nucleus in the modulation of immobilization stress. Neuropeptides 51:43-54. doi: 10.1016/j.npep.2015.03.007

Summary: The CSF-contacting nucleus (CSF-CN) is a brain structure containing neurons that can bidirectionally transmit signals between the brain parenchyma and the CSF. In order to better understand what regulatory peptides modulate this organ, the authors eliminated the CSF-CN of rats with a 500-ng icv injection of CTB-SAP (Cat. #IT-14). Saporin (Cat. #PR-01) was used as a control. The elimination of the CSF-CN worsened the response to chronic immobilization stress; with other data this information suggests that the CSF-CN uses adrenomedullin as a stress-related peptide.

Related Products: CTB-SAP (Cat. #IT-14), Saporin (Cat. #PR-01)

Sato M, Watanabe S (2015) Featured Article: Drug-free selection of stable transfectants using targeted toxin technology and a vector expressing cell-surface carbohydrate-digesting enzyme. Targeting Trends 16(2)

Related Products: IB4-SAP (Cat. #IT-10)

Read the featured article in Targeting Trends.

See Also:

• Sato M et al. A combination of targeted toxin technology and the piggyBac-mediated gene transfer system enables efficient isolation of stable transfectants in nonhuman mammalian cells. Biotechnol J 10:143-153, 2015.

Q: I’m interested in your anti-DBH-saporin toxin for lesioning central catecholaminergic neurons. I see from the product description that the antibody used is a mouse monoclonal – designed to specifically target rat DBH. My interest is to produce targeted lesions in mouse transgenic. Will this product still work specifically? Thanks.

A: Unfortunately, we do not have really good data to support the use of our Anti-DBH-SAP (Cat. #IT-03) in mice. There is significant homology between mouse and rat DBH, however the actual antigen for both the mouse monoclonal we use in the immunotoxin and an alternate unpurified rabbit polyclonal, is native bovine DBH enzyme. For further background information there are two references where our product was used in mice. The references are listed below.

An early sympathetic nervous system influence exacerbates collagen-induced arthritis via CD4+ / CD25+ cells.[1] The sympathetic nervous system can play conflicting roles in collagen-induced arthritis (CIA). CD4+CD25+ T cells can play an immunoregulatory effect in this system depending on the expression of the FoxP3 transcription factor. Mice received 5-µg intraperitoneal injections of anti-DBH-SAP to induce an early sympathectomy. The results indicate that the sympathetic nervous system increases disease severity in CIA by stimulating some of the proinflammatory aspects of CD4+CD25+ T cells.

An opposing time-dependent immune-modulating effect of the sympathetic nervous system conferred by altering the cytokine profile in the local lymph nodes and spleen of mice with type II collagen-induced arthritis.[2] In this work the authors examined the role of the sympathetic nervous system (SNS) in late stages of chronic arthritis. 5 µg intraperitoneal injections of anti-DBH-SAP in mice were used to confirm that previous 6-OHDA injections caused a sympathectomy. The results demonstrate that the SNS supports inflammation during the asymptomatic phase of arthritis, but inhibits inflammation during the chronic symptomatic phase.

Related Products: Anti-DBH-SAP (Cat. #IT-03)

References

1. Harle P et al. An early sympathetic nervous system influence exacerbates collagen-induced arthritis via CD4+CD25+ cells. Arthritis Rheum 58:2347-2355, 2008.
2. Harle P et al. An opposing time-dependent immune-modulating effect of the sympathetic nervous system conferred by altering the cytokine profile in the local lymph nodes and spleen of mice with type II collagen-induced arthritis. Arthritis Rheum 52:1305-1313, 2005.

Peters C, Hayashida K, Suto T, Houle T, Aschenbrenner C, Martin T, Eisenach J (2015) Individual differences in acute pain-induced endogenous analgesia predict time to resolution of postoperative pain in the rat. Anesthesiology 122:895-907. doi: 10.1097/ALN.0000000000000593

Summary: 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.

Related Products: Anti-DBH-SAP (Cat. #IT-03), Mouse IgG-SAP (Cat. #IT-18)

Mittelman-Smith M, Krajewski-Hall S, McMullen N, Rance N (2015) Neurokinin 3 receptor-expressing neurons in the median preoptic nucleus modulate heat-dissipation effectors in the female rat. Endocrinology 156:2552-2562. doi: 10.1210/en.2014-1974

Summary: Kisspeptin and Neurokinin B (NKB) expression in the infundibular, or arcuate, nucleus is increased after menopause. Here the authors investigate whether KNDy (kisspeptin, NKB, and dynorphin expressing) neurons are able to influence cutaneous vasodilation through Neurokinin 3 (NK3)-expressing projections from the median preoptic nucleus (MnPO). Rats received two 10-ng injections of NK3-SAP (Cat. #IT-63) into the MnPO. Blank-SAP (Cat. #IT-21) was used as a control. The data indicate that NK3-expressing neurons in the MnPO facilitate vasodilation.

Related Products: NKB-SAP (Cat. #IT-63), Blank-SAP (Cat. #IT-21)

Dashniani M, Burjanadze M, Naneishvili T, Chkhikvishvili N, Beselia G, Kruashvili L, Pochkhidze N, Chighladze M (2015) Exploratory behavior and recognition memory in medial septal electrolytic, neuro- and immunotoxic lesioned rats. Physiol Res 64:755-767. doi: 10.33549/physiolres.932809

Summary: To investigate recognition memory that incorporates a spatial or temporal component, the authors lesioned the medial septum of rats using several techniques. For specific lesioning of cholinergic neurons rats received bilateral injections of 192-IgG-SAP (Cat. #IT-01, 500 ng total) into the medial septum. Saporin (Cat. #PR-01) was used as a control. While electrolytic lesions produced disruptions of spatial recognition memory, immunotoxin lesions did not, indicating that the cholinergic neurons of the septohippocampal pathway are not essential to processing this type of learning.

Related Products: 192-IgG-SAP (Cat. #IT-01), Saporin (Cat. #PR-01)

Kim T, Thankachan S, McKenna J, McNally J, Yang C, Choi J, Chen L, Kocsis B, Deisseroth K, Strecker R, Basheer R, Brown R, McCarley R (2015) Cortically projecting basal forebrain parvalbumin neurons regulate cortical gamma band oscillations. Proc Natl Acad Sci U S A 112:3535-3540. doi: 10.1073/pnas.1413625112

Summary: 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.

Related Products: mu p75-SAP (Cat. #IT-16)

Burjanadze M, Mataradze S, Rusadze K, Chkhikvishvili N, Dashniani M (2015) Selective lesion of GABA-ergic neurons in the medial septum by GAT1-saporin impairs spatial learning in a water-maze. Georgian Med News 240:59-64.

Summary: The authors investigated the role of GABAergic neurons in the medial septum on spatial learning using a Morris water maze test. Rats received bilateral injections totaling 162 ng of GAT-1-SAP (Cat. #IT-32) into the medial septum. Saporin (Cat. #PR-01) was used as a control. The lesioned animals displayed significant deficits during the water maze task, indicating that GABAergic neurons in the medial septum are intrinsic to organization of spatial map-driven behavior.

Related Products: GAT1-SAP (Cat. #IT-32), Saporin (Cat. #PR-01)

Nguyen H, Huppé-Gourgues F, Vaucher E (2015) Activation of the mouse primary visual cortex by medial prefrontal subregion stimulation is not mediated by cholinergic basalo-cortical projections. Front Syst Neurosci 9:1. doi: 10.3389/fnsys.2015.00001

Summary: 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.

Related Products: mu p75-SAP (Cat. #IT-16)