Anssi Lipponen

Dr. Anssi Lipponen

orcid

Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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15 December 2022 in Frontiers in Microbiology
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Journal Article
Open access
Ananda TiwariAnanda Tiwari
Ananda Tiwari
PKPaula Kurittu
Paula Kurittu
AAAhmad I. Al-Mustapha
Ahmad I. Al-Mustapha
VHViivi Heljanko
Viivi Heljanko
VJVenla Johansson
Venla Johansson
AHAnnamari Heikinheimo
Annamari Heikinheimo
Infectious diseases caused by antibiotic-resistant bacterial (ARB) pathogens are a serious threat to human and animal health. The active surveillance of ARB using an integrated one-health approach can help to reduce the emergence and spread of ARB, reduce the associated economic impact, and guide antimicrobial stewardship programs. Wastewater surveillance (WWS) of ARB provides composite samples for a total population, with easy access to the mixed community microbiome. This concept is emerging rapidly, but the clinical utility, sensitivity, and uniformity of WWS of ARB remain poorly understood especially in relation to clinical evidence in sewershed communities. Here, we systematically searched the literature to identify studies that have compared findings from WWS of ARB and antibiotic resistance genes (ARG) with clinical evidence in parallel, thereby evaluating how likely WWS of ARB and ARG can relate to the clinical cases in communities. Initially, 2,235 articles were obtained using the primary search keywords, and 1,219 articles remained after de-duplication. Among these, 35 articles fulfilled the search criteria, and an additional 13 relevant articles were included by searching references in the primary literature. Among the 48 included papers, 34 studies used a culture-based method, followed by 11 metagenomics, and three PCR-based methods. A total of 28 out of 48 included studies were conducted at the single sewershed level, eight studies involved several countries, seven studies were conducted at national or regional scales, and five at hospital levels. Our review revealed that the performance of WWS of ARB pathogens has been evaluated more frequently for Escherichia coli, Enterococcus spp., and other members of the family Enterobacteriaceae, but has not been uniformly tested for all ARB pathogens. Many wastewater-based ARB studies comparing the findings with clinical evidence were conducted to evaluate the public health risk but not to relate with clinical evidence and to evaluate the performance of WWS of ARB. Indeed, relating WWS of ARB with clinical evidence in a sewershed is not straightforward, as the source of ARB in wastewater cannot be only from symptomatic human individuals but can also be from asymptomatic carriers as well as from animal sources. Further, the varying fates of each bacterial species and ARG within the sewerage make the aim of connecting WWS of ARB with clinical evidence more complicated. Therefore, future studies evaluating the performance of many AMR pathogens and their genes for WWS one by one can make the process simpler and the interpretation of results easier.

31 March 2025 in Nature Medicine
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Journal Article
Open access
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HOHamilton Se-Hwee Oh
Hamilton Se-Hwee Oh
DUDeniz Yagmur Urey
Deniz Yagmur Urey
LKLinda Karlsson
Linda Karlsson
ZZZeyu Zhu
Zeyu Zhu
YSYuanyuan Shen
Yuanyuan Shen
TWTony Wyss-Coray
Tony Wyss-Coray
Rates of cognitive decline in Alzheimer’s disease (AD) are extremely heterogeneous. Although biomarkers for amyloid-beta (Aβ) and tau proteins, the hallmark AD pathologies, have improved pathology-based diagnosis, they explain only 20–40% of the variance in AD-related cognitive impairment (CI). To discover novel biomarkers of CI in AD, we performed cerebrospinal fluid (CSF) proteomics on 3,397 individuals from six major prospective AD case–control cohorts. Synapse proteins emerged as the strongest correlates of CI, independent of Aβ and tau. Using machine learning, we derived the CSF YWHAG:NPTX2 synapse protein ratio, which explained 27% of the variance in CI beyond CSF pTau181:Aβ42, 11% beyond tau positron emission tomography, and 28% beyond CSF neurofilament, growth-associated protein 43 and neurogranin in Aβ+ and phosphorylated tau+ (A+T1+) individuals. CSF YWHAG:NPTX2 also increased with normal aging and 20 years before estimated symptom onset in carriers of autosomal dominant AD mutations. Regarding cognitive prognosis, CSF YWHAG:NPTX2 predicted conversion from A+T1+ cognitively normal to mild cognitive impairment (standard deviation increase hazard ratio = 3.0, P = 7.0 × 10–4) and A+T1+ mild cognitive impairment to dementia (standard deviation increase hazard ratio = 2.2, P = 8.2 × 10–16) over a 15-year follow-up, adjusting for CSF pTau181:Aβ42, CSF neurofilament, CSF neurogranin, CSF growth-associated protein 43, age, APOE4 and sex. We also developed a plasma proteomic signature of CI, which we evaluated in 13,401 samples, which partly recapitulated CSF YWHAG:NPTX2. Overall, our findings underscore CSF YWHAG:NPTX2 as a robust prognostic biomarker for cognitive resilience versus AD onset and progression, highlight the potential of plasma proteomics in replacing CSF measurement and further implicate synapse dysfunction as a core driver of AD dementia.

18 December 2018 in Journal of Extracellular Vesicles
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Journal Article
Open access
Jenni KarttunenJenni Karttunen
Jenni Karttunen
MHMette Heiskanen
Mette Heiskanen
VNVicente Navarro‐Ferrandis
Vicente Navarro‐Ferrandis
SGShalini Das Gupta
Shalini Das Gupta
ALAnssi Lipponen
Anssi Lipponen
APAsla Pitkänen
Asla Pitkänen
The microRNA (miRNA) cargo contained in plasma extracellular vesicles (EVs) offers a relatively little explored source of biomarkers for brain diseases that can be obtained noninvasively. Methods to isolate EVs from plasma, however, are still being developed. For EV isolation, it is important to ensure the removal of vesicle‐free miRNAs, which account for approximately two‐thirds of plasma miRNAs. Membrane particle precipitation‐based EV isolation is an appealing method because of the simple protocol and high yield. Here, we evaluated the performance of a precipitation‐based method to obtain enriched EV‐specific miRNAs from a small volume of rat plasma. We performed size‐exclusion chromatography (SEC) on precipitation‐isolated EV pellets and whole plasma. The SEC fractions were analysed using Nanoparticle Tracking Analysis (NTA), protein and miRNA concentration assays, and droplet digital polymerase chain reaction for four miRNAs (miR‐142‐3p, miR‐124‐3p, miR‐23a, miR‐122). Precipitation‐isolated EVs and selected SEC fractions from the plasma were also analysed with transmission electron microscopy (TEM). Precipitation‐based EV isolation co‐precipitated 9% to 15% of plasma proteins and 21% to 99% of vesicle‐free miRNAs, depending on the individual miRNAs. In addition, the amount of miR‐142‐3p, found mainly in EV fractions, was decreased in the EV fractions, indicating that part of it was lost during precipitation‐based isolation. Western blot and TEM revealed both protein and lipoprotein contamination in the precipitation‐isolated EV‐pellets. Our findings indicate that a precipitation‐based method is not sufficient for purifying plasma EV‐contained miRNA cargo. The particle number measured by NTA is high, but this is mostly due to the contaminating lipoproteins. Although a part of the vesicle‐free miRNA is removed, vesicle‐free miRNA still dominates in plasma EV pellets isolated by the precipitation‐based method.

23 February 2022 in Water Research
Verified
Journal Article
Open access
Ananda TiwariAnanda Tiwari
Ananda Tiwari
ALAnssi Lipponen
Anssi Lipponen
AHAnna-Maria Hokajärvi
Anna-Maria Hokajärvi
OLOskari Luomala
Oskari Luomala
ASAnniina Sarekoski
Anniina Sarekoski
TPTarja Pitkänen
Tarja Pitkänen
Wastewater-based surveillance is a cost-effective concept for monitoring COVID-19 pandemics at a population level. Here, SARS-CoV-2 RNA was monitored from a total of 693 wastewater (WW) influent samples from 28 wastewater treatment plants (WWTP, N = 21–42 samples per WWTP) in Finland from August 2020 to May 2021, covering WW of ca. 3.3 million inhabitants (∼ 60% of the Finnish population). Quantity of SARS-CoV-2 RNA fragments in 24 h-composite samples was determined by using the ultrafiltration method followed by nucleic acid extraction and CDC N2 RT-qPCR assay. SARS-CoV-2 RNA signals at each WWTP were compared over time to the numbers of confirmed COVID-19 cases (14-day case incidence rate) in the sewer network area.

17 August 2016 in Scientific Reports
Verified
Journal Article
Open access
ALAnssi Lipponen
Anssi Lipponen
JPJussi Paananen
Jussi Paananen
NPNoora Puhakka
Noora Puhakka
APAsla Pitkänen
Asla Pitkänen
We aimed to define the chronically altered gene expression signature of traumatic brain injury (TBI-sig) to discover novel treatments to reverse pathologic gene expression or reinforce the expression of recovery-related genes. Genome-wide RNA-sequencing was performed at 3 months post-TBI induced by lateral fluid-percussion injury in rats. We found 4964 regulated genes in the perilesional cortex and 1966 in the thalamus (FDR < 0.05). TBI-sig was used for a LINCS analysis which identified 11 compounds that showed a strong connectivity with the TBI-sig in neuronal cell lines. Of these, celecoxib and sirolimus were recently reported to have a disease-modifying effect in in vivo animal models of epilepsy. Other compounds revealed by the analysis were BRD-K91844626, BRD-A11009626, NO-ASA, BRD-K55260239, SDZ-NKT-343, STK-661558, BRD-K75971499, ionomycin and desmethylclomipramine. Network analysis of overlapping genes revealed the effects on tubulins (Tubb2a, Tubb3, Tubb4b), Nfe2l2, S100a4, Cd44 and Nfkb2, all of which are linked to TBI-relevant outcomes, including epileptogenesis and tissue repair. Desmethylclomipramine modulated most of the gene targets considered favorable for TBI outcome. Our data demonstrate long-lasting transcriptomics changes after TBI. LINCS analysis predicted that these changes could be modulated by various compounds, some of which are already in clinical use but never tested in TBI.

7 March 2023 in Water
Verified
Journal Article
Open access
PDF file
Ananda TiwariAnanda Tiwari
Ananda Tiwari
Sangeet AdhikariSangeet Adhikari
Sangeet Adhikari
SZShuxin Zhang
Shuxin Zhang
TSTamunobelema B. Solomon
Tamunobelema B. Solomon
ALAnssi Lipponen
Anssi Lipponen
Samendra SherchanSamendra Sherchan
Samendra Sherchan
The emergence of new variants of SARS-CoV-2 associated with varying infectivity, pathogenicity, diagnosis, and effectiveness against treatments challenged the overall management of the COVID-19 pandemic. Wastewater surveillance (WWS), i.e., monitoring COVID-19 infections in communities through detecting viruses in wastewater, was applied to track the emergence and spread of SARS-CoV-2 variants globally. However, there is a lack of comprehensive understanding of the use and effectiveness of WWS for new SARS-CoV-2 variants. Here we systematically reviewed published articles reporting monitoring of different SARS-CoV-2 variants in wastewater by following the PRISMA guidelines and provided the current state of the art of this study area. A total of 80 WWS studies were found that reported different monitoring variants of SARS-CoV-2 until November 2022. Most of these studies (66 out of the total 80, 82.5%) were conducted in Europe and North America, i.e., resource-rich countries. There was a high variation in WWS sampling strategy around the world, with composite sampling (50/66 total studies, 76%) as the primary method in resource-rich countries. In contrast, grab sampling was more common (8/14 total studies, 57%) in resource-limited countries. Among detection methods, the reverse transcriptase polymerase chain reaction (RT-PCR)-based sequencing method and quantitative RT-PCR method were commonly used for monitoring SARS-CoV-2 variants in wastewater. Among different variants, the B1.1.7 (Alpha) variant that appeared earlier in the pandemic was the most reported (48/80 total studies), followed by B.1.617.2 (Delta), B.1.351 (Beta), P.1 (Gamma), and others in wastewater. All variants reported in WWS studies followed the same pattern as the clinical reporting within the same timeline, demonstrating that WWS tracked all variants in a timely way when the variants emerged. Thus, wastewater monitoring may be utilized to identify the presence or absence of SARS-CoV-2 and follow the development and transmission of existing and emerging variants. Routine wastewater monitoring is a powerful infectious disease surveillance tool when implemented globally.