{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,1]],"date-time":"2026-08-01T01:43:30Z","timestamp":1785548610143,"version":"3.56.0"},"reference-count":43,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,12,24]],"date-time":"2021-12-24T00:00:00Z","timestamp":1640304000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union - Hungary","award":["EFOP-3.6.1-16-2016-00008"],"award-info":[{"award-number":["EFOP-3.6.1-16-2016-00008"]}]},{"name":"University of Szeged, Szeged, Hungary","award":["Albert Szent-Gy\u00f6rgyi Research Grant"],"award-info":[{"award-number":["Albert Szent-Gy\u00f6rgyi Research Grant"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceutics"],"abstract":"<jats:p>Chlamydia trachomatis (C. trachomatis) is an obligate intracellular bacterium linked to ocular and urogenital infections with potentially serious sequelae, including blindness and infertility. First-line antibiotics, such as azithromycin (AZT) and doxycycline, are effective, but treatment failures have also been reported. Encapsulation of antibiotics in liposomes is considered an effective approach for improving their local effects, bioavailability, biocompatibility and antimicrobial activity. To test whether liposomes could enhance the antichlamydial action of AZT, we encapsulated AZT in different surface-charged elastic liposomes (neutral, cationic and anionic elastic liposomes) and assessed their antibacterial potential against the C. trachomatis serovar D laboratory strain as well as the clinical isolate C. trachomatis serovar F. A direct quantitative polymerase chain reaction (qPCR) method was used to measure chlamydial genome content 48 h post infection and to determine the recoverable chlamydial growth. All the liposomes efficiently delivered AZT to HeLa 229 cells infected with the laboratory Chlamydia strain, exhibiting the minimal inhibitory concentrations (MIC) and the minimal bactericidal concentrations (MBC) of AZT even 4\u20138-fold lower than those achieved with the free AZT. The tested AZT-liposomes were also effective against the clinical Chlamydia strain by decreasing MIC values by 2-fold relative to the free AZT. Interestingly, the neutral AZT-liposomes had no effect on the MBC against the clinical strain, while cationic and anionic AZT-liposomes decreased the MBC 2-fold, hence proving the potential of the surface-charged elastic liposomes to improve the effectiveness of AZT against C. trachomatis.<\/jats:p>","DOI":"10.3390\/pharmaceutics14010036","type":"journal-article","created":{"date-parts":[[2021,12,27]],"date-time":"2021-12-27T01:06:54Z","timestamp":1640567214000},"page":"36","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Liposomal Encapsulation Increases the Efficacy of Azithromycin against Chlamydia trachomatis"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3067-8835","authenticated-orcid":false,"given":"Anita","family":"Bogdanov","sequence":"first","affiliation":[{"name":"Department of Medical Microbiology, Albert Szent-Gy\u00f6rgyi Health Center and Albert Szent-Gy\u00f6rgyi Medical School, University of Szeged, Semmelweis Str. 6, 6725 Szeged, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"L\u00e1szl\u00f3","family":"Janov\u00e1k","sequence":"additional","affiliation":[{"name":"Interdisciplinary Excellence Centre, Department of Physical Chemistry and Materials Science, University of Szeged, Rerrich B\u00e9la Sqr. 1, 6720 Szeged, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jasmina","family":"Vrane\u0161","sequence":"additional","affiliation":[{"name":"Molecular Microbiology Department, Dr. Andrija \u0160tampar Teaching Institute of Public Health, Mirogojska cesta 16, 10000 Zagreb, Croatia"},{"name":"Medical Microbiology Department, University of Zagreb School of Medicine, \u0160alata 3, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tomislav","family":"Me\u0161trovi\u0107","sequence":"additional","affiliation":[{"name":"Clinical Microbiology and Parasitology Unit, Dr. Zora Profozi\u0107 Polyclinic, Bosutska 19, 10000 Zagreb, Croatia"},{"name":"University Centre Vara\u017edin, University North, Ul. 104. Brigade 3, 42000 Vara\u017edin, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6405-6922","authenticated-orcid":false,"given":"Sun\u010danica","family":"Ljubin-Sternak","sequence":"additional","affiliation":[{"name":"Molecular Microbiology Department, Dr. Andrija \u0160tampar Teaching Institute of Public Health, Mirogojska cesta 16, 10000 Zagreb, Croatia"},{"name":"Medical Microbiology Department, University of Zagreb School of Medicine, \u0160alata 3, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zsuzsanna","family":"Cseh","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology, Albert Szent-Gy\u00f6rgyi Health Center and Albert Szent-Gy\u00f6rgyi Medical School, University of Szeged, Semmelweis Str. 6, 6725 Szeged, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9402-3857","authenticated-orcid":false,"given":"Val\u00e9ria","family":"Endr\u00e9sz","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology, Albert Szent-Gy\u00f6rgyi Health Center and Albert Szent-Gy\u00f6rgyi Medical School, University of Szeged, Semmelweis Str. 6, 6725 Szeged, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1300-2374","authenticated-orcid":false,"given":"Katalin","family":"Buri\u00e1n","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology, Albert Szent-Gy\u00f6rgyi Health Center and Albert Szent-Gy\u00f6rgyi Medical School, University of Szeged, Semmelweis Str. 6, 6725 Szeged, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"\u017deljka","family":"Vani\u0107","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Technology, Faculty of Pharmacy and Biochemistry, University of Zagreb, A. Kova\u010di\u0107a 1, 10000 Zagreb, Croatia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dezs\u0151 P.","family":"Virok","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology, Albert Szent-Gy\u00f6rgyi Health Center and Albert Szent-Gy\u00f6rgyi Medical School, University of Szeged, Semmelweis Str. 6, 6725 Szeged, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,24]]},"reference":[{"key":"ref_1","unstructured":"(2021, December 23). Trachoma Key Facts (World Health Organization). Available online: https:\/\/www.who.int\/News-Room\/Fact-Sheets\/Detail\/Trachoma."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Smolarczyk, K., Mlynarczyk-Bonikowska, B., Rudnicka, E., Szukiewicz, D., Meczekalski, B., Smolarczyk, R., and Pieta, W. (2021). The Impact of Selected Bacterial Sexually Transmitted Diseases on Pregnancy and Female Fertility. Int. J. Mol. 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