Volume 06 · Issue 03 · 2024

The high morbidity and mortality rate of individuals with human immunodeficiency virus (HIV) / acquired immunodeficiency syndrome (AIDS) coinfected with Mycobacterium tuberculosis (MTB) is a tough challenge for current global tuberculosis prevention and control efforts. HIV/MTB coinfection is more complex than a single infection, and the interaction between the two diseases aggravates the deterioration caused by the disease, resulting in increased hospitalizations and deaths. Rapid screening and early diagnosis facilitate the timely initiation of anti-tuberculosis treatment in HIV/MTB coinfected individuals, thereby reducing transmission and the incidence of adverse prognoses. To date, pathogenic detection has remained the gold standard for diagnosing tuberculosis, but its sensitivity and specificity are greatly affected by the body's immune status, which limits its application in the diagnosis of HIV/MTB coinfection. Recently, immunology and molecular detection technology has developed rapidly. New detection technologies, such as interferon-γ release assays, interferon-gamma inducible protein 10, and GeneXpert MTB/RIF assay have overcome the limitations of traditional detection methods, significantly improved the sensitivity and specificity of tuberculosis diagnosis, and brought new hope to the detection of HIV/MTB coinfection. In this article, the principle, scope of application, and latest research progress of relevant detection methods are reviewed to provide a reference for the early diagnosis of HIV/MTB coinfection.

Since the outbreak of the coronavirus disease 2019 (COVID-19) epidemic in 2019, the public health system has faced enormous challenges. Tracking the individuals who test positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a key step for interrupting chains of transmission of SARS-CoV-2 and reducing COVID-19-associated mortality. With the increasing of asymptomatic infections, it is difficult to track asymptomatic infections through epidemiological surveys and virus whole-genome sequencing. However, due to the cross-reactivity of neutralizing antibodies produced by multiple virus subtypes, neutralizing antibody detection cannot be used to determine whether an individual has a history of infection with a specific subtype of SARS-CoV-2. We recruited 4 human leukocyte antigen A2 (HLA-A2) infections, 15 individuals who received three doses of inactivated vaccines, and 30 breakthrough infections after vaccination and discussed a case-tracking approach to detect epitope-specific CD8⁺ T cells in the peripheral blood of close contacts, including accurate HLA typing based on ribonucleic acid (RNA)-sequencing and flow cytometry data and the comparison and characterization of SARS-CoV-2 HLA-A2 and HLA-A24 epitope-specific CD8⁺ T cells. From individuals who received three doses of inactivated vaccine, we observed that the CD8⁺ T cell specificity for ancestral epitopes was significantly higher than for mutated epitopes, and the fold change of CD8⁺ T cells corresponding to mutated epitopes relative to ancestral epitopes was less than 1. The enzyme-linked immunospot (ELISpot) results further validate this result. This study forms a "method for understanding the infection history of SARS-CoV-2 subtypes based on the proportion of epitope-specific CD8⁺ T cells in the peripheral blood of subjects", covering up to 46 % of the population, including HLA-A2⁺ and HLA-A24⁺ donors, providing a novel method for SARS-CoV-2 infected case tracing.

Inactivated coronavirus disease 2019 (COVID-19) vaccines such as CoronaVac and BBIBP-CorV have been widely used in China. However, more investigation is still needed to understand antibodies' duration and effectiveness against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants in the real world. In this study, 575 participants who had been vaccinated with two or three doses of the inactivated vaccine were recruited. Serum samples were collected and tested for anti-spike IgG and neutralizing antibodies against SARS-CoV-2 (original strain, Dela, and Omicron). Unsurprisingly, a third dose of the vaccine significantly enhanced antibody responses against SARS-CoV-2 and its variants. However, despite a booster dose, the neutralizing antibody levels against Omicron, particularly the BA.5.2 subvariant, remained low. There was no sex bias, but an age bias was observed. Notably, the predominant IgG subclass antibodies were IgG1 and IgG2, with a much lower level of IgG4. After the booster shot, the ratio of IgG4 to IgG1 significantly increased. The observation of IgG1 to the IgG4 class switch after repeated inactivated vaccinations underscores the importance of continuous monitoring of subclass antibody responses. Further clinical investigations are required to understand the implications of this class switch for optimizing immunization strategies.

To explore the impact of ursodeoxycholic acid (UDCA) on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and clinical outcomes in patients with autoimmune liver disease (AILD). Patients diagnosed with AILD were enrolled and divided into a UDCA group and a non-UDCA group based on whether they received UDCA treatment. Relevant data were collected regarding AILD diagnosis, treatment, biochemical indicators, and imaging examination. The incidence of SARS-CoV-2 infection and the prognosis of AILD patients were observed. A total of 1,138 patients completed follow-up. The usage rate of hormone (P = 0.003) and immunosuppressant (P = 0.001) used for treating AILD in the non-UDCA group was markedly lower than in the UDCA group. The UDCA usage rate was markedly lower in SARS-CoV-2 infected patients than in uninfected patients (P = 0.003). The rate of SARS-CoV-2 infection in the non-UDCA group was significantly higher than in the UDCA group (P = 0.018). Logistic regression analysis showed that UDCA use (P = 0.003) was correlated to a lower incidence of SARS-CoV-2, while immunosuppressant use (P = 0.017) increased the incidence. Recovery time from SARS-CoV-2 infection was markedly longer for those receiving UDCA treatment than those in the non-UDCA group (P = 0.018). UDCA is associated with low SARS-CoV-2 incidence in AILD patients, while immunosuppressant increases its incidence instead. Patients receiving UDCA treatment have a longer recovery time after being infected.

Enterovirus D68 (EV-D68) infection causes severe acute respiratory infection and severe neurological complications, such as acute flaccid myelitis (AFM), in children. However, although EV-D68 has pandemic potential, no effective drugs or vaccines are currently clinically available. Furthermore, EV-D68 infection-induced inflammatory response and cell death are not fully understood. In this study, we demonstrated that several inflammatory cytokines were upregulated in a multiplicity of infection (MOI) dependent manner in EV-D68-infected human rhabdomyosarcoma (RD) cells. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) confirmed that tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), C-C motif chemokine ligand-5 (CCL-5), and CXC motif chemokine ligand-5 (CXCL-5) mRNA levels were highly upregulated after EV-D68 infection. IL-1β processing and maturation mediated by caspase-8 was inhibited by the caspase-8 inhibitor Z-IETD-FMK. EV-D68 infection activates caspase-8 to mediate IL-1β maturation and secretion. Additionally, EV-D68 activated cell death-related proteins such as caspase-3, poly (ADP-ribose) polymerase 1 (PARP-1), phosphorylation of Mixed Lineage Kinase domain-like protein (pMLKL), and gasdermin E (GSDME). Thus, EV-D68 infection activates caspase-8, which triggers the necroptosis and apoptosis pathways. Overall, our data suggest that caspase-8 activation is associated with the inflammatory response and cell death in EV-D68-infected RD cells. This mechanism represents a novel target for the treatment of EV-D68 infection by inhibiting caspase-8 activation.

The matrix protein 2 (M2) is a preferred target for developing a universal vaccine against the influenza A virus (IAV). This study aimed to develop a method for assessing antibody-dependent cell-mediated cytotoxicity (ADCC) associated with M2-based immunization in mice. We first established a stable cell line derived from mouse lymphoma cells (YAC-1) expressing M2 of H3N2. This cell line, designated as YAC-1-M2, was generated using a second-generation lentiviral tricistronic plasmid system to transduce the M2 gene into YAC-1 cells. The ADCC effect induced by polyclonal antibodies targeting matrix protein 2 ectodomain (M2e) was demonstrated by YAC-1-M2 cell lysis by natural killer cells (NK) derived from mice, in the presence of anti-M2 antibodies obtained from mice immunized with an mRNA vaccine based on M2e. This ADCC effect was found to be stronger compared to the effect induced by monoclonal antibodies (14C2) against M2. Moreover, the ADCC effect was enhanced as the effector-to-target ratio of NK to YAC-1-M2 cells increased. In conclusion, we established a novel method to detect ADCC of M2 of IAV, which paves the way for the development of an M2-based universal vaccine against IAV and an in-depth analysis of its mechanism of broad-spectrum immune protection in mice.

Ceftazidime-avibactam (CZA) is a recently approved combination synthetic β-lactamase inhibitor used in human clinical medicine. Cases of CZA resistance in humans have already been reported, but limited research has investigated CZA resistance in pets. This study explored the prevalence and transmission of CZA-resistant Escherichia coli (CZAREC) among pets, their owners, veterinarians, and the environment in animal hospitals. A total of 5,419 clinical samples were collected from dogs and cats, along with samples from the environment (n = 5,843), veterinarians (n = 557), and pet owners (n = 368) in animal hospitals. From these samples, 760 Escherichia coli (E. coli) isolates were obtained, out of which 60 were identified as CZAREC. These included 34 isolates from the environment (9.14 %, n = 372), three from veterinarians (8.11 %, n = 37), and 23 from animals (6.82 %, n = 337). No CZAREC isolates were found in pet owners. The predominant sequence types of CZARECs were ST156 (n = 20), ST410 (n = 19) and ST101 (n = 7). Bayesian analysis revealed six clusters comprising 47 isolates from the hospital environment, pets, and veterinaries, displaying genetic relatedness of less than 100 core genome single nucleotide polymorphisms (cgSNPs) between any two isolates in each cluster. Some CZAREC isolates with high genetic similarity persisted in the same animal hospital for four to six months. Moreover, discriminant analysis of principal components indicated that most isolates from different hosts shared a genetic source in the human/dog/cat merged cluster. Overall, evidence of CZARECs transmission was found among pets, the environment, and veterinarians in animal hospitals. The findings emphasize the importance of monitoring CZARECs in the veterinary clinical setting to ensure the health of both pets and humans.

Mpox is a zoonotic infectious disease caused by the mpox virus (MPXV). Historically, the majority of mpox cases have been documented in Central Africa. However, since May 2022, there has been a notable rise in reported cases from regions beyond Africa. Currently, over 110 countries spanning Europe, North America, South America, Asia, and other territories have reported mpox infections. This report details a case involving a patient who identifies as a man who has sex with men (MSM) and is concurrently infected with MPXV, human immunodeficiency virus type 1 (HIV-1), Pneumocystis jiroveci, as well as extensively drug-resistant tuberculosis (XDR-TB). This patient had also received a vaccination for smallpox in the past. Additionally, we provide photographic documentation charting the progression of dermatological manifestations associated with mpox. This case highlights the significance of sexual intercourse as a crucial mode of transmission for mpox. The rapid and widespread dissemination of the MPXV across various regions, especially among MSM communities, underscores the importance of enhancing preventive education efforts targeted at high-risk populations.