Immune cell interactions in tuberculosis.

Despite having been identified as the organism that causes tuberculosis in 1882, Mycobacterium tuberculosis has managed to still evade our understanding of the protective immune response against it, defying the development of an effective vaccine. Technology and novel experimental models have revealed much new knowledge, particularly with respect to the heterogeneity of the bacillus and the host response. This review focuses on certain immunological elements that have recently yielded exciting data and highlights the importance of taking a holistic approach to understanding the interaction of M. tuberculosis with the many host cells that contribute to the development of protective immunity.

B cells promote granulomatous inflammation during chronic Mycobacterium tuberculosis infection in mice.

The current study reveals that in chronic TB, the B cell-deficient µMT strain, relative to wild-type (WT) C57BL/6 mice, displays in the lungs lower levels of inflammation that are associated with decreased CD4+ T cell proliferation, diminished Th1 response, and enhanced levels of interleukin (IL)-10. The latter result raises the possibility that B cells may restrict lung expression of IL-10 in chronic TB. These observations are recapitulated in WT mice depleted for B cells using anti-CD20 antibodies. IL-10 receptor (IL-10R) blockade reverses the phenotypes of decreased inflammation and attenuated CD4+ T cell responses in B cell-depleted mice. Together, these results suggest that in chronic murine TB, B cells, by virtue of their capacity to restrict expression of the anti-inflammatory and immunosuppressive IL-10 in the lungs, promote the development of a robust protective Th1 response, thereby optimizing anti-TB immunity. This vigorous Th1 immunity and restricted IL-10 expression may, however, allow the development of inflammation to a level that can be detrimental to the host. Indeed, decreased lung inflammation observed in chronically infected B cell-deficient mice, which exhibit augmented lung IL-10 levels, is associated with a survival advantage relative to WT animals. Collectively, the results reveal that in chronic murine TB, B cells play a role in modulating the protective Th1 immunity and the anti-inflammatory IL-10 response, which results in augmentation of lung inflammation that can be host-detrimental. Intriguingly, in tuberculous human lungs, conspicuous B cell aggregates are present in close proximity to tissue-damaging lesions manifesting necrosis and cavitation, suggesting the possibility that in human TB, B cells may contribute to the development of exacerbated pathology that is known to promote transmission. Since transmission is a major hindrance to TB control, investigating into whether B cells can shape the development of severe pulmonic pathological responses in tuberculous individuals is warranted.

Multiple genetic paths including massive gene amplification allow Mycobacterium tuberculosis to overcome loss of ESX-3 secretion system substrates.

Mycobacterium tuberculosis (Mtb) possesses five type VII secretion systems (T7SS), virulence determinants that include the secretion apparatus and associated secretion substrates. Mtb strains deleted for the genes encoding substrates of the ESX-3 T7SS, esxG or esxH, require iron supplementation for in vitro growth and are highly attenuated in vivo. In a subset of infected mice, suppressor mutants of esxG or esxH deletions were isolated, which enabled growth to high titers or restored virulence. Suppression was conferred by mechanisms that cause overexpression of an ESX-3 paralogous region that lacks genes for the secretion apparatus but encodes EsxR and EsxS, apparent ESX-3 orphan substrates that functionally compensate for the lack of EsxG or EsxH. The mechanisms include the disruption of a transcriptional repressor and a massive 38- to 60-fold gene amplification. These data identify an iron acquisition regulon, provide insight into T7SS, and reveal a mechanism of Mtb chromosome evolution involving "accordion-type" amplification.

A proteome-wide analysis unveils a core Epstein-Barr virus antibody signature of classic Hodgkin lymphoma across ethnically diverse populations.

Epstein-Barr virus (EBV) is an oncogenic virus associated with various malignancies, including classical Hodgkin lymphoma (cHL). Despite its known association, the specific role of humoral immune response to EBV remains poorly characterized in cHL. To address this, we conducted a study using a custom protein microarray to measure the antibody responses in cHL patients and matched healthy controls recruited from an East-Asian hospital-based case-control study. We identified 16 IgG antibodies significantly elevated in EBV-positive cHL compared with controls, defining an "East-Asian antibody signature of EBV-positive cHL." We evaluated responses against these 16 antibodies in a distinct European population, leveraging data from our previous European cHL case-control study from the UK, Denmark, and Sweden. A subset of antibodies (14/16, 87.5%) from the "East-Asian antibody signature of EBV-positive cHL" exhibited significant associations with cHL in the European population. Conversely, we assessed the "European antibody signature of EBV-positive cHL" identified in our prior study which consisted of 18 EBV antibodies (2 IgA, 16 IgG), in the East-Asian population. A subset of these antibodies (15/18, 83.3%) maintained significant associations with cHL in the East-Asian population. This cross-comparison of antibody signatures underscores the robust generalizability of EBV antibodies across populations. Five anti-EBV IgG antibodies (LMP-1, TK, BALF2, BDLF3, and BBLF1), found in both population-specific antibody signatures, represent a "core signature of EBV-positive cHL." Our findings suggest that the antibody responses targeting these core EBV proteins reflect a specific EBV gene expression pattern, serving as potential biomarkers for EBV-positive cHL independent of population-specific factors.

Mycobacterial phosphodiesterase Rv0805 is a virulence determinant and its cyclic nucleotide hydrolytic activity is required for propionate detoxification.

Cyclic AMP (cAMP) signaling is essential to Mycobacterium tuberculosis (Mtb) pathogenesis. However, the roles of phosphodiesterases (PDEs) Rv0805, and the recently identified Rv1339, in cAMP homeostasis and Mtb biology are unclear. We found that Rv0805 modulates Mtb growth within mice, macrophages and on host-associated carbon sources. Mycobacterium bovis BCG grown on a combination of propionate and glycerol as carbon sources showed high levels of cAMP and had a strict requirement for Rv0805 cNMP hydrolytic activity. Supplementation with vitamin B12 or spontaneous genetic mutations in the pta-ackA operon restored the growth of BCGΔRv0805 and eliminated propionate-associated cAMP increases. Surprisingly, reduction of total cAMP levels by ectopic expression of Rv1339 restored only 20% of growth, while Rv0805 complementation fully restored growth despite a smaller effect on total cAMP levels. Deletion of an Rv0805 localization domain also reduced BCG growth in the presence of propionate and glycerol. We propose that localized Rv0805 cAMP hydrolysis modulates activity of a specialized pathway associated with propionate metabolism, while Rv1339 has a broader role in cAMP homeostasis. Future studies will address the biological roles of Rv0805 and Rv1339, including their impacts on metabolism, cAMP signaling and Mtb pathogenesis.

Development of non-sedating benzodiazepines with in vivo antischistosomal activity.

The neglected tropical disease schistosomiasis infects over 200 million people worldwide and is treated with just one broad-spectrum antiparasitic drug (praziquantel). Alternative drugs are needed in the event of emerging praziquantel resistance or treatment failure. One promising lead that has shown efficacy in animal models and a human clinical trial is the benzodiazepine meclonazepam, discovered by Roche in the 1970s. Meclonazepam was not brought to market because of dose-limiting sedative side effects. However, the human target of meclonazepam that causes sedation (GABAARs) is not orthologous to the parasite targets that cause worm death. Therefore, we were interested in whether the structure of meclonazepam could be modified to produce antiparasitic benzodiazepines that do not cause host sedation. We synthesized 18 meclonazepam derivatives with modifications at different positions on the benzodiazepine ring system and tested them for in vitro antiparasitic activity. This identified five compounds that progressed to in vivo screening in a murine model, two of which cured parasite infections with comparable potency to meclonazepam. When these two compounds were administered to mice that were run on the rotarod test, both were less sedating than meclonazepam. These findings demonstrate the proof of concept that meclonazepam analogs can be designed with an improved therapeutic index and point to the C3 position of the benzodiazepine ring system as a logical site for further structure-activity exploration to further optimize this chemical series.

Fifth Edition of the World Health Organization Classification of Tumors of the Hematopoietic and Lymphoid Tissues: Mature T-Cell, NK-Cell, and Stroma-Derived Neoplasms of Lymphoid Tissues.

This review focuses on mature T cells, natural killer (NK) cells, and stroma-derived neoplasms in the fifth edition of the World Health Organization classification of hematolymphoid tumors, including changes from the revised fourth edition. Overall, information has expanded, primarily due to advancements in genomic understanding. The updated classification adopts a hierarchical format. The updated classification relies on a multidisciplinary approach, incorporating insights from a diverse group of pathologists, clinicians, and geneticists. Indolent NK-cell lymphoproliferative disorder of the gastrointestinal tract, Epstein-Barr virus-positive nodal T- and NK-cell lymphoma, and several stroma-derived neoplasms of lymphoid tissues have been newly introduced or included. The review also provides guidance on how the fifth edition of the World Health Organization classification of hematolymphoid tumors can be applied in routine clinical practice.

Exploring U.S. Hispanic origin groups diagnosed with uterine cancer - Are there disparities?

OBJECTIVE: To evaluate patterns and trends of uterine cancer among Hispanic subgroups. METHODS: The United States Cancer Statistics (USCS), National Cancer Database (NCDB), and World Population Review were used to obtain data on incidence, demographic characteristics, and cancer histology. Joinpoint regression program was used for statistical analysis. RESULTS: Based on 2001-2017 USCS data, the overall incidence of uterine cancer was 27.46 vs. 23.29/100,000 in Hispanics vs. non-Hispanic Whites. There was an over 2-fold higher annual increase in the incidence in Hispanics (1.94%; p < 0.001) vs. Whites (0.85%; p < 0.001), particularly in local stage disease. There was an increase in grade 1 endometrioid carcinoma (1.48%; p < 0.001 vs. -0.52%; p = 0.1) and aggressive histologic subtypes (4.04% p = 0.000 vs. 2.53% p = 0.000) in Hispanics vs. Whites. Using the NCDB (2004-2015), we analyzed 17,351 Hispanics by subgroup (Mexican, South/Central American, Puerto Rican, Cuban, and Dominican). Over the 12 years, there was an increase in the proportion of uterine cancer diagnoses in all Hispanics (5.2% to 11.0%; p < 0.0001). Dominican patients experienced the largest increase in diagnosis (2.6% to 14.9%; p < 0.0001), the highest proportion of advanced disease at 28.0% (p < 0.0001), and the highest incidence of non-endometrioid histologies at 37.1% (p < 0.0001). World Population Review 2023 revealed the highest female obesity rates in Puerto Rico (51.4%), the Dominican Republic (34.1%), and Mexico (32.8%). CONCLUSION: Uterine cancer incidence is increased in Hispanics, with the largest increase in Dominican women with more advanced stages and high-risk histologic subtypes. The impact of obesity on cancer risk, especially in Puerto Ricans, Dominicans, and Mexicans, warrants further investigation.

Uterine cancer among Asian Americans - Disparities & clinical characteristics.

OBJECTIVE: To evaluate the patterns and trends of uterine cancer among Asian subgroups living in the U.S. METHODS: Data were obtained from United States Cancer Statistics (2001-2017), National Cancer Database (2004-2015), and World Population Review (2023). SEER*Stat version 8.3.9.2, Joinpoint regression program 4.9.0.0, and SAS v 9.4 were employed for statistical analysis. RESULTS: Based on data from 778,891 women in the United States Cancer Statistics database, Asians had a 3.4-fold higher rate of incident uterine cancer compared to White populations (2.14% vs. 0.63%; p < 0.001). Using the National Cancer Database, 7,641 Asian women from six subgroups were analyzed: Filipino, Korean, Indian/Pakistani, Vietnamese, Chinese, and Japanese. Indian and Pakistani women had the greatest increase in the proportion of cancer diagnoses (5.0% to 14.4%; p = 0.0003). Additionally, Indian and Pakistani patients had higher comorbidity scores while Koreans had the lowest (22.7% vs. 10.7%, p < 0.0001). Regarding stage of disease, 25.3% of Filipinos presented with advanced stage disease compared to 19.2% of Indians and Pakistanis (p = 0.0001). Furthermore, Filipinos had the highest proportion of non-endometrioid cancers at 18.4% compared to other subgroups (p = 0.0003). Using the World Population Review, female obesity was highest in Pakistan (8.6%) and the Philippines (7.5%) and lowest in Vietnam (2.6%). CONCLUSION: Uterine cancer incidence increased at higher rates among Asians compared to White populations. Specifically, Indian and Pakistani uterine cancer patients were more likely to have higher comorbidity rates and Filipino patients had more advanced stage cancer with non-endometrioid histologies than other Asian subgroups. Further research is warranted to better understand these trends.

Preoperative and pre-chemotherapy CA-125 levels in high-risk early-stage ovarian cancer - An NRG/GOG study.

OBJECTIVES: To determine clinical significance of preoperative and pre-chemotherapy CA-125 in high-risk early-stage epithelial ovarian cancer patients. METHODS: All patients with stage IA/IB and grade 3, stage IC, clear cell, or completed resected stage II cancer were enrolled in a phase III trial and treated with chemotherapy. Kaplan-Meier method and Cox proportional hazards model were used for statistical analyses. RESULTS: 427 patients with high-risk early-stage ovarian cancer were enrolled. Of 213 patients with preoperative CA-125 data, 79% had elevated CA-125. Median preoperative CA-125 level was 103 U/mL. Patients with ≤10, 11-15, and > 15 cm tumors had median preoperative CA-125 levels of 62, 131 and 158 U/mL, respectively (p = 0.002). For the 350 patients with data for pre-chemotherapy CA-125 level, 69% had elevated pre-chemotherapy CA-125 above 35 U/mL with median value of 65 U/mL. However, age, race, stage, cell type and grade of disease were not correlated with CA-125 levels before and after surgery. On multivariate analysis, elevated pre-chemotherapy CA-125 independently predicted worse recurrence-free survival (HR = 2.13, 95% CI: 1.23-3.69; p = 0.007) and overall survival (HR = 1.99, 95% CI: 1.10-3.59; p = 0.022) after adjusting for age, stage, cell type and grade of disease. Compared to those with normal CA-125, patients with elevated pre-chemotherapy CA-125 had lower recurrence-free survival (RFS, 87% vs. 75%; p = 0.007) and overall survival (OS, 88% vs. 82%; p = 0.02). However, preoperative CA-125 was not prognostic of RFS (p = 0.699) or OS (p = 0.701). CONCLUSIONS: Preoperative CA-125 was elevated in nearly 80% of high-risk early-stage ovarian cancer patients. Pre-chemotherapy CA-125 was associated with recurrence-free and overall survival; however, preoperative CA-125 was not prognostic.