Immunotoxins (ITs), which consist of antibodies conjugated to toxins, have been proposed as a treatment for cancer and chronic infections. To develop and improve the ITs, different toxins such as ricin, have been used, aiming for higher efficacy against target cells. The toxin pulchellin, isolated from the Abrus pulchellus plant, has similar structure and function as ricin. Here we have compared two plant toxins, recombinant A chains from ricin (RAC) and pulchellin (PAC) toxins, for their ability to kill HIV Env-expressing cells. In this study, RAC and PAC were produced in E. coli, and chromatographically purified, then chemically conjugated to two different anti-HIV monoclonal antibodies (MAbs), anti-gp120 MAb 924 or anti-gp41 MAb 7B2. These conjugates were characterized biochemically and immunologically. Cell internalization was studied by flow cytometry and confocal microscopy. Results showed that PAC can function within an effective IT. The ITs demonstrated specific binding against native antigens on persistently HIV-infected cells and recombinant antigens on Env-transfected cells. PAC cytotoxicity appears somewhat less than RAC, the standard for comparison. This is the first report that PAC may have utility for the design and construction of therapeutic ITs, highlighting the potential role for specific cell targeting.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5548917 | PMC |
http://dx.doi.org/10.1038/s41598-017-08037-3 | DOI Listing |
Background: The autophagy lysosomal pathway (ALP) and the ubiquitin-proteasome system (UPS) are key proteostasis mechanisms in cells, which are dysfunctional in AD and linked to protein aggregation and neuronal death. Autophagy is over activated in Alzheimer's disease brain whereas UPS is severely impaired. Activating autophagy has received most attention, however recent evidence suggests that UPS can clear aggregate proteins and a potential therapeutic target for AD and protein misfolding diseases.
View Article and Find Full Text PDFBackground: Alzheimer's disease (AD) is the most common cause of dementia worldwide. It is characterized by dysfunction in the U1 small nuclear ribonucleoproteins (snRNPs) complex, which may precede TAU aggregation, enhancing premature polyadenylation, spliceosome dysfunction, and causing cell cycle reentry and death. Thus, we evaluated the effects of a synthetic single-stranded cDNA, called APT20TTMG, in induced pluripotent stem cells (iPSC) derived neurons from healthy and AD donors and in the Senescence Accelerated Mouse-Prone 8 (SAMP8) model.
View Article and Find Full Text PDFBackground: Immunotherapy of Alzheimer's disease (AD) is a promising approach to reducing the accumulation of beta-amyloid, a critical event in the onset of the disease. Targeting the group II metabotropic glutamate receptors, mGluR2 and mGluR3, could be important in controlling Aβ production, although their respective contribution remains unclear due to the lack of selective tools.
Method: 5xFAD mice were chronically treated by a brain penetrant camelid single domain antibody (VHH or nanobody) that is an activator of mGluR2.
Alzheimers Dement
December 2024
Columbia University Irving Medical Center, New York, NY, USA.
Background: Genetic studies indicate a causal role for microglia, the innate immune cells of the central nervous system (CNS), in Alzheimer's disease (AD). Despite the progress made in identifying genetic risk factors, such as CD33, and underlying molecular changes, there are currently limited treatment options for AD. Based on the immune-inhibitory function of CD33, we hypothesize that inhibition of CD33 activation may reverse microglial suppression and restore their ability to resolve inflammatory processes and mitigate pathogenic amyloid plaques, which may be neuroprotective.
View Article and Find Full Text PDFBackground: Our previous study identified that Sildenafil (a phosphodiesterase type 5 [PDE5] inhibitor) is a candidate repurposable drug for Alzheimer's Disease (AD) using in silico network medicine approach. However, the clinically meaningful size and mechanism-of-actions of sildenafil in potential prevention and treatment of AD remind unknown.
Method: We conducted new patient data analyses using both the MarketScan® Medicare with Supplemental database (n = 7.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!