Biomedical subjects

Preethi H Gunaratne

Publications and source records attributed to Preethi H Gunaratne.

6 recordsLinked to original sources

PubMed2026

Psilocybin prevents chemotherapy-induced peripheral neuropathy through mitochondrial trafficking preservation.

Chemotherapy-induced peripheral neuropathy (CIPN) is a disabling, often irreversible toxicity that affects millions of patients, limits life-saving cancer therapy, and lacks proven treatment. In this work, we show that as little as two doses of psilocybin before chemotherapy durably prevented the onset of CIPN across platinum- and taxane-based models, including repeated chemotherapy cycles, without impairing antitumor efficacy. Peripherally, psilocybin maintained tactile sensitivity and intraepidermal nerve fiber endings through axonal mitochondrial trafficking and distribution preservation, through the TrkB-Akt-PAK5-MAP2-KIF5B pathway and remobilization of syntaphilin-anchored mitochondria. Centrally, it normalized medial prefrontal cortical synaptic activity and cortical alpha and beta electroencephalography power. This stabilization of peripheral axonal energy balance establishes psilocybin as a first-in-class prophylactic agent for CIPN while also preserving central neural function. Given psilocybin's established safety, these discoveries support clinical evaluation as a strategy to prevent CIPN.

Animals↗

PubMed2026

Spatial biology reveals altered macrophage states in immunosuppressed non-melanoma skin cancer.

Immunosuppressed patients with non-melanoma skin cancer experience worse clinical outcomes, yet the tumor immune microenvironment associated with systemic immunosuppression remains incompletely defined. Using integrated single-cell, spatial transcriptomic, multiplex immunofluorescence, and spatial epigenomic profiling across immunocompetent and immunosuppressed tumors, we found that overall immune-cell composition was largely preserved despite differences in immune-cell distribution, spatial organization, and T cell clonality. Immunosuppressed tumors demonstrated reduced intratumoral macrophage densities, decreased T cell clonal diversity, altered antigen-presenting cell and T cell spatial interactions, and distinct fibroblast- and macrophage-associated spatial niches. Multi-cohort validation across complementary spatial and single-cell platforms identified consistent alterations in innate-adaptive immune organization in immunosuppressed tumors. Together, these findings define spatial and functional remodeling of the tumor immune microenvironment under systemic immunosuppression and provide a framework for future therapeutic investigation in high-risk patients.

Humans↗

PubMed2004

The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC).

The National Institutes of Health's Mammalian Gene Collection (MGC) project was designed to generate and sequence a publicly accessible cDNA resource containing a complete open reading frame (ORF) for every human and mouse gene. The project initially used a random strategy to select clones from a large number of cDNA libraries from diverse tissues. Candidate clones were chosen based on 5'-EST sequences, and then fully sequenced to high accuracy and analyzed by algorithms developed for this project. Currently, more than 11,000 human and 10,000 mouse genes are represented in MGC by at least one clone with a full ORF. The random selection approach is now reaching a saturation point, and a transition to protocols targeted at the missing transcripts is now required to complete the mouse and human collections. Comparison of the sequence of the MGC clones to reference genome sequences reveals that most cDNA clones are of very high sequence quality, although it is likely that some cDNAs may carry missense variants as a consequence of experimental artifact, such as PCR, cloning, or reverse transcriptase errors. Recently, a rat cDNA component was added to the project, and ongoing frog (Xenopus) and zebrafish (Danio) cDNA projects were expanded to take advantage of the high-throughput MGC pipeline.

Animals↗

PubMed2004

Large-scale RT-PCR recovery of full-length cDNA clones.

Pseudogenes, alternative transcripts, noncoding RNA, and polymorphisms each add extensive complexity to the mammalian transcriptome and confound estimation of the total number of genes. Despite advanced algorithms for gene prediction and several large-scale efforts to obtain cDNA clones for all human open reading frames (ORFs), no single collection is complete. To enhance this effort, we have developed a high-throughput pipeline for reverse transcription PCR (RT-PCR) gene recovery. Most importantly, novel molecular strategies for improving RT-PCR yield of transcripts that have been difficult to isolate by other means and computational strategies for clone sequence validation have been developed and optimized. This systematic gene recovery pipeline allows both rescue of predicted human and rat genes and provides insight into the complexity of the transcriptome through comparisons with existing data sets.

Automation↗

PubMed2002

Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences.

The National Institutes of Health Mammalian Gene Collection (MGC) Program is a multiinstitutional effort to identify and sequence a cDNA clone containing a complete ORF for each human and mouse gene. ESTs were generated from libraries enriched for full-length cDNAs and analyzed to identify candidate full-ORF clones, which then were sequenced to high accuracy. The MGC has currently sequenced and verified the full ORF for a nonredundant set of >9,000 human and >6,000 mouse genes. Candidate full-ORF clones for an additional 7,800 human and 3,500 mouse genes also have been identified. All MGC sequences and clones are available without restriction through public databases and clone distribution networks (see http:mgc.nci.nih.gov).

Algorithms↗

PubMedDate not supplied

Concatenation cDNA sequencing for transcriptome analysis.

We describe a high-throughput cDNA sequencing pipeline (http://www.hgsc.bcm.tmc.edu/projects/cdna) built in response to the emerging need for rapid sequencing of large cDNA collections. Using this strategy cDNA inserts are purified and joined through concatenation into large molecules. These 'pseudo-BACs' are subjected to random shotgun sequencing whereby the majority of cDNA inserts in the pool are sequenced. Using this concatenation cDNA sequencing platform, we have contributed more than 13000 full-length cDNA sequences from human and mouse to the Mammalian Gene Collection (MGC).

Cloning, Molecular↗