Diss. (sammanfattning) Stockholm : Karolinska institutet, 2005. / Härtill 5 uppsatser.

Thesis (M.S.)--Uniformed Services University of the Health Sciences, 2006 / Typescript (photocopy)

Untreatable gonorrhea, caused by fully antimicrobial resistant Neisseria gonorrhoeae (GC), is a major global health threat. While a vaccine would greatly help address this crisis, development of a GC vaccine is complicated by the lack of lab models of symptomatic gonorrhea. We hypothesized that overt disease in animal models of gonorrhea is limited by the human-restriction of gonococcal virulence factors, and the impact of the reproductive hormone cycle (estrus and diestrus phases). We tested these hypotheses by examining the host response to infection in transgenic mice expressing targets of bacterial adhesion, human carcinoembryonic antigen-related cell adhesion molecules (hCEACAMs), in uterine versus vaginal infections, and in different phases of the reproductive cycle (estrus and diestrus phases). hCEACAM expression most impacted estrus phase infections, prolonging colonization in vaginal infection and inducing greater inflammation in uterine. Reproductive phase greatly influenced host response to uterine infection as diestrus infection was more inflammatory than estrus. Phase differences in uterine infection were driven by greater activation of a chemokine-centric common anti gonococcal response and unique induction of type 1 interferons in diestrus. These findings suggest that symptomatic uterine and vaginal GC infection can be modeled by transcervically infected wild-type diestrus mice and transgenic, vaginally-infected estrus mice, respectively. A novel approach to GC vaccine development is also needed. Mono-antigenic vaccines have failed to produce immunity suggesting a poly-antigenic antigen, like natural outer membrane vesicles (nOMVs) may be necessary. It has been shown that any GC vaccine must lack the bacterioprotective antigen, reduction modifiable protein (RMP), and no such nOMV has been previously described. Here we report successful isolation of RMP-deficient nOMVs through sequential size and weight restrictive filtration. Vesicle morphology, proteomics, and bioactivity was characterized via various methods. nOMVs were found to be consistent in size, shape and antigenic load. As antigens, nOMVs induced high serum titers and measurable vaginal levels of antigen and GC specific IgG that recognized several nOMV immunogens supporting the vaccine potential of GC nOMVs. These findings lay the groundwork for protective studies of nOMV vaccines in novel models of active gonorrhea moving the field closer to discovering the mechanism of protective anti-gonococcal immunity.

Chlamydia trachomatis (Ct) is an obligate intracellular human pathogen. It causes blinding trachoma and sexually transmitted disease such as chlamydia, pelvic inflammatory disease and lymphogranuloma venereum. Ct has a unique biphasic development cycle and replicates in an intracellular vacuole called inclusion. Normally it has two forms: the infectious form, elementary body (EB); and the non-infectious form, reticulate body (RB). Ct is not easily amenable to genetic manipulation. Hence, to understand the infection process, it is crucial to study how the metabolic activity of Ct exactly evolves in the host cell and what roles of EB and RB play differentially in Ct metabolism during infection. In addition, Ct was found regularly coinfected with other pathogens in patients who got sexually transmitted diseases (STDs). A lack of powerful methods to culture Ct outside of the host cell makes the detailed molecular mechanisms of coinfection difficult to study. In this work, a genome-scale metabolic model with 321 metabolites and 277 reactions was first reconstructed by me to study Ct metabolic adaptation in the host cell during infection. This model was calculated to yield 84 extreme pathways, and metabolic flux strength was then modelled regarding 20hpi, 40hpi and later based on a published proteomics dataset. Activities of key enzymes involved in target pathways were further validated by RT-qPCR in both HeLa229 and HUVEC cell lines. This study suggests that Ct's major active pathways involve glycolysis, gluconeogenesis, glycerolphospholipid biosynthesis and pentose phosphate pathway, while Ct's incomplete tricarboxylic acid cycle and fatty acid biosynthesis are less active. EB is more activated in almost all these carbohydrate pathways than RB. Result suggests the survival of Ct generally requires a lot of acetyl-CoA from the host. Besides, both EB and RB can utilize folate biosynthesis to generate NAD(P)H but may use different pathways depending on the demands of ATP. When more ATP is available from both host cell and Ct itself, RB is more activated by utilizing energy providing chemicals generated by enzymes associated in the nucleic acid metabolism. The forming of folate also suggests large glutamate consumption, which is supposed to be converted from glutamine by the glutamine-fructose-6-phosphate transaminase (glmS) and CTP synthase (pyrG). Then, RNA sequencing (RNA-seq) data analysis was performed by me in a coinfection study. Metatranscriptome from patient RNA-seq data provides a realistic overview. Thirteen patient samples were collected and sequenced by our collaborators. Six male samples were obtained by urethral swab, and seven female samples were collected by cervicovaginal lavage. All the samples were Neisseria gonorrhoeae (GC) positive, and half of them had coinfection with Ct. HISAT2 and Stringtie were used for transcriptomic mapping and assembly respectively, and differential expression analysis by DESeq2, Ballgown and Cuffdiff2 are parallelly processed for comparison. Although the measured transcripts were not sufficient to assemble Ct's transcriptome, the differential expression of genes in both the host and GC were analyzed by comparing Ct positive group (Ct+) against Ct-uninfected group. The results show that in the Ct+ group, the host MHC class II immune response was highly induced. Ct infection is associated with the regulation of DNA methylation, DNA double-strand damage and ubiquitination. The analysis also shows Ct infection enhances host fatty acid beta oxidation, thereby inducing mROS, and the host responds to reduce ceramide production and glycolysis. The coinfection upregulates GC's own ion transporters and amino acid uptake, while it downregulates GC's restriction and modification systems. Meanwhile, GC has the nitrosative and oxidative stress response and also increases the ability for ferric uptake especially in the Ct+ group compared to Ct-uninfected group. In conclusion, methods in bioinformatics were used here in analyzing the metabolism of Ct itself, and the responses of the host and GC respectively in a coinfection study with and without Ct. These methods provide metabolic and metatranscriptomic details to study Ct metabolism during infection and Ct associated coinfection in the human microbiota. / Chlamydia trachomatis (Ct) ist ein obligater intrazellulärer Pathogen des Menschen. Er verursacht Trachoma und sexuell übertragbare Krankheiten, wie Chlamydiose, Unterleibsentzündung und Lymphogranuloma venereum. Ct besitzt einen biphasischen Entwicklungszyklus und vermehrt sich in intrazellulären Vakuolen, sogenannten Einschlusskörperchen. Normalerweise können zwei Formen beobachtete werden: Die infektiöse Form, Elementarkörperchen (EK); und die nicht-infektiöse Form, Retikularkörperchen (RK). Ct ist nicht einfach genetisch zu manipulieren. Um den Infektionsablauf besser zu verstehen, ist es wichtig, zu untersuchen, wie sich genau die metabolische Aktivität von Ct in der Wirtszelle entwickelt und welche Rolle EK und RK im Metabolismus von Ct während der Infektion spielen. Zusätzlich wurde Ct häufig bei Patienten mit sexuell übertragbaren Krankheiten (STD) in Co-Infektion mit anderen Erregern gefunden. Ein Mangel an leistungsfähigen Methoden zur Kultivierung von Ct außerhalb der Wirtszelle macht es schwierig die genauen molekularen Mechanismen von Co-Infektionen zu untersuchen. In dieser Arbeit wurde erstmals ein genomweites metabolisches Model mit 321 Metaboliten und 277 Reaktionen aufgebaut, um die metabolische Adaption von Ct in der Wirtzelle während der Infektion zu untersuchen. Dieses Model wurde erstellt und umfasst 84 „extreme pathways“ (Grenz-Stoffwechselwege). Darauf aufbauend wurde die metabolische Fluss-Stärke berechnet. Die Zeitpunkte 20 hpi (20 Stunden nach der Infektion), 40 hpi und die anschließende Infektionsphase wurden durch Nutzung von Proteom-Daten modelliert. Die Aktivitäten von Schlüsselenzymen, welche in wichtigen Stoffwechselwegen involviert sind, wurden zusätzlich durch RT-qPCR überprüft. Dabei wurden die Ergebnisse sowohl für HeLA229- als auch HUVEC-Zellen nachgemessen. Diese Untersuchungen zeigten, dass Ct’s wichtigste aktive Stoffwechselwege die Glykolyse, die Gluconeogenese und der Pentosephosphatweg sind, während der unvollständige Zitronensäurezyklus und die Fettsäuresynthese weniger aktiv sind. Gegenüber RK sind bei EK fast alle diese Kohlenhydratwege stärker aktiviert. Im Allgemeinen benötigt Ct eine größere Menge an Acetyl-CoA. Außerdem können sowohl EK, als auch RK die Folsäurebiosynthese nutzen, um NAD(P)H zu generieren. Dabei werden möglicherweise unterschiedliche Pathways genutzt, abhängig vom Bedarf an ATP. Sobald mehr ATP sowohl durch die Wirtszellen als auch von der Ct-Zelle selbst zur Verfügung steht, wird die Nutzung von Energieträgern, produziert durch Enzyme des Nukleinsäurestoffwechsels, in RK stärker aktiviert. Die Bildung von Folsäure lässt den Schluss zu, dass große Mengen von Glutamat umgesetzt werden, welches vermutlich aus der Umwandlung von Glutamin durch die Glutamine-fructose-6-phosphate-transaminase (glmS) und CTP-Syntase (pyrG) stammt. Anschließend wurde eine Analyse von RNA-Sequenzierungsdaten (RNA-seq) aus einer Co-Infektions-Studie (Chlamydien und andere Keime, insbesondere Gonokokken (GC)) durchgeführt. Dafür wurden Proben von dreizehn Patienten gesammelt und von Kollaborationspartnern sequenziert. Sechs Proben männlicher Patienten wurden durch Abstrich der Harnröhre und sieben Proben weiblicher Patientinnen durch cervicovaginale Lavage gewonnen. Alle Proben waren Neisseria gonorrhoeae (GC) positiv, wobei die Hälfte eine Co-Infektion mit Ct aufwies. Die Programme HISAT2 and Stringtie wurden zum Abbilden der transgenomischen Reads beziehungsweise zur Assemblierung des Genoms verwendet, und eine Analyse der differentiellen Expression wurde jeweils mit DESeq2, Ballgown und Cuffdiff2 durchgeführt und die Ergebnisse verglichen. Obwohl nicht ausreichend viele Transkripte von Ct gewonnen werden konnten, um das Transkriptom komplett assemblieren zu können, wurde die differentielle Expression der Gene sowohl von Wirt als auch von GC durch den Vergleich zwischen der Gruppe der Ct-positiven (Ct+) der Gruppe der Ct-unifizierten Patienten analysiert. Die Ergebnisse zeigten, dass in der (Ct+)-Gruppe die auf der MHC-Klasse-II basierte Immunantwort stark induziert war. Die Infektion von Ct ist mit der Regulation der DNA-Methylierung, DNA-Doppel-Strang-Schädigung und Ubiquitinierung verbunden. Die Analyse zeigte zusätzlich, dass die Infektion mit Ct die Fettsäure β-Oxidation des Wirts steigert, dadurch mROS induziert, und sowohl die Ceramid-Produktion als auch die Glycolyse reduziert. Die Co-Infektion reguliert GC’s eigene Eisentransporter und Aminosäureaufnahme hoch, während Restriktions- und Modifikationssysteme herunterreguliert werden. Gleichzeitig zeigt GC sowohl eine stickstoffsensitve Stress Antwort als auch eine oxidative. Dies verstärkt zusätzlich die Fähigkeit für die Aufnahme von Eisen, insbesondere in der (Ct+)-Gruppe. Zusammenfassend wurden Methoden der Bioinformatik genutzt, um den Metabolismus von Ct selbst, und die Antwort des Wirtes respektive GC‘s in einer Co-Infektionsstudie mit und ohne Ct zu analysieren. Diese Methoden lieferten wichtige metabolische und metatranskriptomische Details, um den Metabolismus von Ct während der Infektion, aber auch das Mikrobiom während einer Ct assoziierter Co-Infektion zu untersuchen.

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The emergence of drug resistance towards existing drugs is a constant challenge in the fight against many diseases including Malaria and gonorrhoeae. To evade resistance, new targets must be engaged, and to do that, new structural classes of anti-infective must be prepared and evaluated. During the course of my PhD journey, I had the opportunity to investigate and optimize the antimalarial candidate (±)-2-3b, and salicylic acid (4-1a) as an anti-gonorrhea treatment. Malaria is a life-threatening mosquito-borne disease. In 2021, there were 247 million cases of malaria and the estimated number of malaria deaths stood at 619,000. Because of the rapid development of resistance to all current antimalarials, discovery of antimalarials with unexploited mechanisms of action is critical to reduce malaria mortality. In the Carlier group, our initial approach focused on discovery of inhibitors of the methylerythritol phosphate (MEP) pathway for isoprenoid precursor biosynthesis, since this pathway is essential for Plasmodium falciparum and absent in human. Application of the isopentenyl pyrophosphate (IPP) chemical rescue screen to the compounds of the Malaria Box, a collection of 400 antimalaria candidates with unknown mechanisms of action, identified tetrahydro-β-carboline 2-1 (MMV008138) as an inhibitor of the MEP pathway. Chapter 2 of this work discusses similarity searching of the Novartis portion of the hit set (5K compounds), from the original 20K compound hit set of the Malaria Box, and identifying tetrahydro-β-carboline GNF-Pf-5009, designated as (±)-2-3b. Preparation of pure enantiomers, by resolution, demonstrated the pharmacological superiority of (R)-2-3b over (S)-2-3b, which was found to have good asexual blood stage (ABS) inhibition potency against malarial parasites P. falciparum, and low general cytotoxicity. However, (R)-2-3b was found not orally efficacious in a P. berghei mouse model of malaria. We concluded that the lack of oral efficacy of (R)-2-3b was due to its poor drug-like qualities, in particular its high molecular weight and low solubility. Chapter 3 of this work explores modifications of (R)-2-3b ((R)-3-5Aa) that were expected to improve its properties. We show that the new compounds (R)-3-5Gm and (R)-3-5Gk not only are more potent in vitro than (R)-2-3b ((R)-3-5Aa), but also have molecular weights < 500 g/mol. Neisseria gonorrhoeae is the causative agent of the sexually transmitted disease gonorrhea. Due to the increased rates of infection as well as the prevalence of multidrug-resistant N. gonorrhoeae strains worldwide, the World Health Organization (WHO) and the U.S. Centers for Disease Control and Prevention (CDC) list N. gonorrhoeae at the highest possible threat level to public health. Dual therapy of azithromycin (AZM) and ceftriaxone has been the standard-of-care for treatment of gonococcal infections. However, due to increasing resistance to azithromycin (>33% in some regions) the CDC removed AZM from the treatment regimen for gonorrhea in 2020. Therefore, ceftriaxone remains the only recommended antibiotic for treatment of gonococcal infections. However, increasing resistance to this treatment option has been reported, consequently there is an urgent need to identify novel therapeutics against N. gonorrhoeae. Drug repurposing is a popular strategy that explores new therapeutic opportunities for approved drugs with available information on their pharmacokinetic data, dosages, and toxicity. Salicylic acid is a highly privileged chemical scaffold. Also, the use of salicylic acid to treat sexually transmitted diseases (including gonorrhea) was reported as early as the 19th century. Recently, Dr. Mohamed N. Seleem reported that salicylic acid (4-1a) exhibited modest activity against N. gonorrhoeae strains including the AZM-resistant strain (CDC-181). Chapter 4 of this work illustrates how the anti-gonococcal activity in this scaffold is easily lost by inopportune substitution. However, we found that substituted naphthyl analogs (4-3b,o,p) have superior activity to salicylic acid itself. In addition, the three analogs showed high selectivity, compared to AZM, against N. gonorrhoeae over the vaginal microbiota. / Doctor of Philosophy / In the fight against malaria and gonorrhea, two different diseases, we face one common challenge, which is the emergence of drug resistance towards existing drugs. Therefore, there is a pressing need for new antimalarial and anti-gonorrhea compounds with novel mechanisms of action. This dissertation encompasses my research on the investigation and optimization of the antimalarial candidate (±)-2-3b and Salicylic acid (4-1a) as anti-gonorrhea treatment. Malaria is a life-threatening mosquito-borne disease. It is transmitted through the bites of infected female Anopheles mosquitoes. In 2021, there were 247 million cases of malaria and the estimated number of malaria deaths stood at 619,000. Children under 5 accounted for about 80% of all malaria deaths. In the Carlier group, compound 2-1 (MMV008138) was identified and thoroughly studied as antimalaria candidate. It was found to be effective in killing the malaria parasite, P. falciparum, in red blood cells, in vitro. However, when tested on P. berghei mouse model of malaria, it was found not effective. Chapter 2 of this work discusses the discovery of (±)-2-3b after searching for a structurally similar analog of 2-1. The compound (±)-2-3b can exist in two distinct spatial arrangements (enantiomers) R and S. After preparation of pure enantiomers, we confirmed the pharmacological superiority of (R)-2-3b over (S)-2-3b. The compound (R)-2-3b showed good activity in vitro against malarial parasites P. falciparum, and low general cytotoxicity. However when tested orally on P. berghei mouse model of malaria, it was found not effective. We concluded that the lack of oral efficacy of (R)-2-3b was due to its poor drug-like qualities, such as high molecular weight and low solubility. Chapter 3 of this work explore modifications of (R)-2-3b ((R)-3-5Aa) that will improve its properties. We show that the new compounds (R)-3-5Gm and (R)-3-5Gk not only are more active in vitro than (R)-2-3b ((R)-3-5Aa), but also have lower molecular weights (< 500 g/mol). Neisseria gonorrhoeae is the causative agent of the sexually transmitted disease gonorrhea. The World Health Organization (WHO) and the U.S. Centers for Disease Control and Prevention (CDC) list N. gonorrhoeae at the highest possible threat level to public health because of the increased rates of infection and the appearance of multidrug-resistant N. gonorrhoeae strains worldwide. Dual therapy of azithromycin (AZM) and ceftriaxone has been the standard-of-care for treatment of gonococcal infections. However, due to increasing resistance to azithromycin the CDC removed AZM from the treatment regimen. Therefore, ceftriaxone remains the only recommended antibiotic for treatment of gonococcal infections. However, increasing resistance to this treatment option has been reported. Drug repurposing is a popular strategy that explores new therapeutic opportunities for approved drugs with available information on their pharmacokinetic data, dosages, and toxicity. Salicylic acid is a highly privileged chemical scaffold that has been used to treat sexually transmitted diseases (including gonorrhea) since the 19th century. Chapter 4 of this work illustrates our efforts to enhance the potency of salicylic acid (4- 1a). I performed chemical modifications on (4-1a) and concluded that anti-gonococcal activity is easily lost by inopportune substitution. However, we found that substituted naphthyl analogs (4-3b,o,p) have superior activity to salicylic acid itself. In addition, the three analogs showed high selectivity, compared to AZM, against N. gonorrhoeae over the vaginal microbiota.

Background: Selected factors place Dominican female adolescent and adults at risk for sexually transmitted infections (STIs) such as Chlamydia, causative organism Chlamydia trachomatis, and Gonorrhea, causative organism Neisseria gonorrhoeae. The purpose of this study was to determine the prevalence of Chlamydia and Gonorrhea among adolescent and adult females that utilize the clinic in Veron, Dominican Republic. Clinical standards of care for these STIs and educational programs for prevention were developed from the data gathered from this study. Significance at 0.05 ά of the relationship of educational level, management of risk factors and other selected independent variables on prevalence rate of Chlamydia and Gonorrhea in the clinic population of Veron, Dominican Republic were determined. The objectives of the study were to 1) determine the prevalence of adolescent and young adult females diagnosed with Gonorrhea and Chlamydia who visit the clinic for prenatal visits, annual pap smear exams and gynecological complaints; 2) determine the extent to which educational level is a predictor of positive diagnosis or risk for infection of Chlamydia and Gonorrhea and; 3) determine which selected demographic and risk factors are associated with positive test results for Gonorrhea and Chlamydia. Methods: All adolescent and adult females ages 15 years and older visiting the clinic in Veron for prenatal exams, pap smear exams and gynecological complaints between January 28, 2008 – March 3, 2008 were invited to participate in this prevalence study. Of the 90 invited, the accepting sample was 90 who signed an informed consent form. Prior to STI testing each patient completed a verbal interview and questionnaire on sociodemographic characteristics as well as knowledge, attitudes, and beliefs related to Chlamydia and gonorrhea, sexual experiences and behaviors and illicit drugs use. Specimens collected from the endocervical canal of each female were tested and results provided within two hours, followed by immediate treatment by a licensed Dominican physician and follow-up care based on the guidelines and standards of care. The data were analyzed using descriptive statistics, chi square, t-test and logistic regression. Results: A total of ninety women participated in the study. Chlamydia was detected in 6.7% of the patient population and Gonorrhea was detected in 22.2% of the patient population. Co-infection of both Chlamydia and Gonorrhea was present in 2 cases. Among the positive Chlamydia tests results, 50% had less than a six-year education and 50% had more then six years of education. In addition, 83.3% of the patients with positive Chlamydia results answered "yes", they could read and 16.6% stated they could not read, while 83.3% of the patients with positive Chlamydia results stated they could write and 16.6% stated they could not write (P>0.05). Among the patients that tested positive for Gonorrhea, 55% stated they had less than six years of formal education and 45% had more than six years of formal education (P>0.05). There were 75% of the patients that tested positive for Gonorrhea that stated they could read and 25% who stated they could not read (P>0.05); while 85% of the patients with positive Gonorrhea results stated they could write and 15% stated they could not write (P> 0.05). Conclusion: Educational level and other selected demographic characteristics and risk factors in this study are not a significant predictor of positive diagnosis or risk of infection for Chlamydia or Gonorrhea. We cannot conclude that specific risk factors are associated with positive test results for Gonorrhea and Chlamydia. For the physicians involved in the clinical decision-making regarding the female patients at the Veron clinic, more data are needed to determine appropriate populations for screening of Gonorrhea and Chlamydia as well as appropriate educational tools on sexually transmitted infections. / Ph. D.

A profilaxia pré-exposição (PrEP) ao HIV se consolidou como uma importante estratégia de combate ao avanço da epidemia. Ainda assim, a incidência de casos da infecção vem aumentando na população jovem, assim como a de outras infecções sexualmente transmissíveis (ISTs), que atuam como importante fator de risco para transmissão do HIV-1. Entre as infecções mais frequentemente diagnosticadas estão Chlamydia trachomatis (CT) e Neisseria gonorrhoeae (NG). A presença de lesões na mucosa genital e anal são fatores de risco estabelecidos para a transmissão do HIV-1, porém o impacto das infecções assintomáticas ainda é pouco conhecido. Dados recentes mostram que a ativação sistêmica de linfócitos T é um fator de risco para a aquisição da infecção pelo HIV-1. Nesse estudo, estudamos a ativação de linfócitos T na presença de infecção anorretal assintomática por CT e/ou NG. Células mononucleares do sangue periférico de voluntários do PrEP Brasil, um estudo clínico demonstrativo de PrEP ao HIV em homens que fazem sexo com homens, foram descongeladas para análise da ativação de linfócitos T. Trinta e quatro participantes com swab anorretal positivo para CT e/ou NG foram selecionados, enquanto assintomáticos e negativos para outras ISTs. Trinta e cinco controles foram selecionados randomicamente. Encontramos uma maior frequência de linfócitos T CD8+ HLA-DR+CD38+ (1,5 vs. 0,9% p < 0,005) no grupo com infecção assintomática. Os linfócitos T CD8+ de memória também apresentaram uma maior expressão dos marcadores de ativação. Os marcadores de exaustão e senescência foram significantemente mais expressos no grupo com a infecção. Não foi observado aumento ou diferença nos níveis de CD14 solúvel no plasma. Nossos achados demonstram que as infecções anorretais assintomáticas por CT e NG induzem a ativação sistêmica de linfócitos T CD8+. Considerando a alta prevalência dessas infecções e o risco associado de aquisição da infecção pelo HIV-1, o rastreamento periódico e o tratamento sistemático devem sem explorados em conjunto com as estratégias de prevenção ao HIV / Oral antiretroviral pre-exposure prophylaxis (PrEP) has been established as a pivotal strategy in the prevention against HIV epidemic. However, the incidence of HIV-1 infections has been rising among the youth, as well as other sexually transmitted infections (STIs), acting as an important risk factor for HIV-1 acquisition. Infection by Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) are among the most diagnosed. Although the presence of mucosal lesions is a known risk factor for HIV-1 acquisition, the potential increase in risk associated with asymptomatic STIs is not completely understood. Recent data defined higher T cell activation as a single risk factor for sexually acquired HIV-1 infection. We examined the effect of asymptomatic CT and/or NG anorectal infection on immune activation. Peripheral blood mononuclear cells from participants of PrEP Brasil, a study of daily oral PrEP among healthy men who have sex with men, were analyzed for T cell activation by flow cytometry. Thirty-four participants with positive anorectal swab for CT and/or NG were selected, while negative for other STIs and without any reported symptoms. Thirty-five controls were randomly selected. We found a higher frequency of CD8+ HLA-DR+CD38+ T cells (1.5 vs. 0.9% p < 0.005) in the group with CT and/or NG infection and a greater median proportions of activation markers expression in CD8+ T cells with memory phenotype. Exhaustion and senescence markers were also significant higher in the infected group. No difference was observed in the soluble CD14 levels. Our findings suggest that asymptomatic CT and NG anorectal infection lead to a systemic activation of the T cell compartment. Considering the high prevalence of asymptomatic infection and the risk of HIV-1 acquisition associated, regular screening and treatment should be explored as an adjuvant tool for HIV prevention