HIV-1 Myeloid Reservoirs - Contributors to Viral Persistence and Pathogenesis

PURPOSE OF REVIEW

HIV reservoirs are the main barrier to cure. CD4+ T cells have been extensively studied as the primary HIV-1 reservoir. However, there is substantial evidence that HIV-1-infected myeloid cells (monocytes/macrophages) also contribute to viral persistence and pathogenesis.

RECENT FINDINGS

Recent studies in animal models and people with HIV-1 demonstrate that myeloid cells are cellular reservoirs of HIV-1. HIV-1 genomes and viral RNA have been reported in circulating monocytes and tissue-resident macrophages from the brain, urethra, gut, liver, and spleen. Importantly, viral outgrowth assays have quantified persistent infectious virus from monocyte-derived macrophages and tissue-resident macrophages. The myeloid cell compartment represents an important target of HIV-1 infection. While myeloid reservoirs may be more difficult to measure than CD4+ T cell reservoirs, they are long-lived, contribute to viral persistence, and, unless specifically targeted, will prevent an HIV-1 cure.

Monocyte-derived macrophages contain persistent latent HIV reservoirs

The development of persistent cellular reservoirs of latent human immunodeficiency virus (HIV) is a critical obstacle to viral eradication since viral rebound takes place once anti-retroviral therapy (ART) is interrupted. Previous studies show that HIV persists in myeloid cells (monocytes and macrophages) in blood and tissues in virologically suppressed people with HIV (vsPWH). However, how myeloid cells contribute to the size of the HIV reservoir and what impact they have on rebound after treatment interruption remain unclear. Here we report the development of a human monocyte-derived macrophage quantitative viral outgrowth assay (MDM-QVOA) and highly sensitive T cell detection assays to confirm purity. We assess the frequency of latent HIV in monocytes using this assay in a longitudinal cohort of vsPWH (n = 10, 100% male, ART duration 5-14 yr) and find half of the participants showed latent HIV in monocytes. In some participants, these reservoirs could be detected over several years. Additionally, we assessed HIV genomes in monocytes from 30 vsPWH (27% male, ART duration 5-22 yr) utilizing a myeloid-adapted intact proviral DNA assay (IPDA) and demonstrate that intact genomes were present in 40% of the participants and higher total HIV DNA correlated with reactivatable latent reservoirs. The virus produced in the MDM-QVOA was capable of infecting bystander cells resulting in viral spread. These findings provide further evidence that myeloid cells meet the definition of a clinically relevant HIV reservoir and emphasize that myeloid reservoirs should be included in efforts towards an HIV cure.

Higher circulating intermediate monocytes are associated with cognitive function in women with HIV

BACKGROUND

Identifying a quantitative biomarker of neuropsychiatric dysfunction in people with HIV (PWH) remains a significant challenge in the neuroHIV field. The strongest evidence to date implicates the role of monocytes in central nervous system (CNS) dysfunction in HIV, yet no study has examined monocyte subsets in blood as a correlate and/or predictor of neuropsychiatric function in virally suppressed PWH.

METHODS

In 2 independent cohorts of virologically suppressed women with HIV (vsWWH; n = 25 and n = 18), whole blood samples were obtained either in conjunction with neuropsychiatric assessments (neuropsychological [NP] test battery, self-report depression and stress-related symptom questionnaires) or 1 year prior to assessments. Immune cell subsets were assessed by flow cytometry.

RESULTS

A higher proportion of intermediate monocytes (CD14⁺CD16⁺) was associated with lower global NP function when assessing monocytes concurrently and approximately 1 year before (predictive) NP testing. The same pattern was seen for executive function (mental flexibility) and processing speed. Conversely, there were no associations with monocyte subsets and depression or stress-related symptoms. Additionally, we found that a higher proportion of classical monocytes was associated with better cognition.

CONCLUSION

Although it is widely accepted that lentiviral infection of the CNS targets cells of monocyte-macrophage-microglial lineage and is associated with an increase in intermediate monocytes in the blood and monocyte migration into the brain, the percentage of intermediate monocytes in blood of vsWWH has not been associated with neuropsychiatric outcomes. Our findings provide evidence for a new, easily measured, blood-based cognitive biomarker in vsWWH.

FUNDING

R01-MH113512, R01-MH113512-S, P30-AI094189, R01-MH112391, R01-AI127142, R00-DA044838, U01-AI35004, and P30-MH075673

Behavior and development of Tetranychus ludeni Zacher, 1913 (Acari: Tetranychidae) and physiological stress in genetically modified cotton expressing Cry1F and Cry1Ac proteins

Genetically modified plants are one of the tactics used in integrated pest management - IPM. There is great concern about the impact of these plants on non-target organisms. On the other hand, there is little information in the literature on the effects of transgenics (Bacillus thuringiensis) Bt on populations of phytophagous mites, and the physiological responses that this attack promotes on plants. The objective of this work was to evaluate the biology of the T. ludeni mite in Bt cotton, expressing the Cry1F and Cry1Ac proteins. To evaluate the behavior of food and oviposition preference of the T. ludeni with Bt cotton and isohybrid. Verify if the physiological stress caused by T. ludeni's attack is differentiated in Bt cotton. The mites were reared in Bt cotton and isohybrid, in a total of 40 replicates in the completely randomized design and the biological cycle was evaluated. The food preference and oviposition analysis were done with 10 replicates, with choice. The physiological stress was evaluated through chlorophyll fluorescence, under greenhouse conditions. The data of the T. ludeni biology were analyzed by Student's t-test, for food and oviposition preference the chi-square test was performed. Regression models were fitted for the fluorescence parameters. The model identity test was used to evaluate the differences between Bt and isohybrid treatments. Cry1F and Cry1Ac proteins have not affected the biology of T. ludeni. The photosynthetic parameters in Bt cotton plants were less influenced by T. ludeni infestation.

Myeloid and CD4 T Cells Comprise the Latent Reservoir in Antiretroviral Therapy-Suppressed SIVmac251-Infected Macaques

Human immunodeficiency virus (HIV) eradication or long-term suppression in the absence of antiretroviral therapy (ART) requires an understanding of all viral reservoirs that could contribute to viral rebound after ART interruption. CD4 T cells (CD4s) are recognized as the predominant reservoir in HIV type 1 (HIV-1)-infected individuals. However, macrophages are also infected by HIV-1 and simian immunodeficiency virus (SIV) during acute infection and may persist throughout ART, contributing to the size of the latent reservoir. We sought to determine whether tissue macrophages contribute to the SIVmac251 reservoir in suppressed macaques. Using cell-specific quantitative viral outgrowth assays (CD4-QVOA and MΦ-QVOA), we measured functional latent reservoirs in CD4s and macrophages in ART-suppressed SIVmac251-infected macaques. Spleen, lung, and brain in all suppressed animals contained latently infected macrophages, undetectable or low-level SIV RNA, and detectable SIV DNA. Silent viral genomes with potential for reactivation and viral spread were also identified in blood monocytes, although these cells might not be considered reservoirs due to their short life span. Additionally, virus produced in the MΦ-QVOA was capable of infecting healthy activated CD4s. Our results strongly suggest that functional latent reservoirs in CD4s and macrophages can contribute to viral rebound and reestablishment of productive infection after ART interruption. These findings should be considered in the design and implementation of future HIV cure strategies.IMPORTANCE This study provides further evidence that the latent reservoir is comprised of both CD4+ T cells and myeloid cells. The data presented here suggest that CD4+ T cells and macrophages found throughout tissues in the body can contain replication-competent SIV and contribute to rebound of the virus after treatment interruption. Additionally, we have shown that monocytes in blood contain latent virus and, though not considered a reservoir themselves due to their short life span, could contribute to the size of the latent reservoir upon entering the tissue and differentiating into long-lived macrophages. These new insights into the size and location of the SIV reservoir using a model that is heavily studied in the HIV field could have great implications for HIV-infected individuals and should be taken into consideration with the development of future HIV cure strategies.

Evaluation of genetic diversity in fig accessions by using microsatellite markers

Fig (Ficus carica L.) is a fruit of great importance worldwide. Its propagation is carried out with stem cuttings, a procedure that favors the occurrence of synonymy among specimens. Thus, molecular markers have become an important tool for studies of DNA fingerprinting, germplasm characterization, and genetic diversity evaluation in this plant species. The aim of this study was the analysis of genetic diversity among accessions of fig and the detection of synonyms among samples using molecular markers. Five microsatellite markers previously reported as polymorphic to fig were used to characterize 11 fig cultivars maintained in the germplasm bank located in Lavras, Minas Gerais. A total of 21 polymorphic DNA fragments were amplified, with an average of 4.2 alleles per locus. The average allelic diversity and polymorphic information content were 0.6300 and 0.5644, respectively, whereas the total value for the probability of identity was 1.45 x 10(-4). The study allowed the identification of 10 genotypes and 2 synonymous individuals. The principal coordinate analysis showed no defined clusters despite the formation of groups according to geographical origin. However, neighbor-joining analysis identified the same case of synonymy detected using principal coordinate analysis. The data also indicated that the fig cultivars analyzed constitute a population of individuals with high genetic diversity and a broad range of genetic variation.

[Bibliographic study of the mother-child relationship: basis for pediatric and neonatal care]

The study consists of a bibliographical review about the mother and son attachment and its considerations in nursing care intervention, in the child's hospitalization process. In deciding to study this theme we had the purpose to obtain knowledge that would be useful in daily pediatric and neonatal nursing practice. We evidenced the importance of knowledge dissemination about the attachment among the nursing professionals, because their performance can interfere in a significant way in the hospitalized child's social and emotional development. However, in spite of the importance of the theme, few scientific studies in the nursing area were published. For our theoretical knowledge we searched another knowledge areas as psychology, sociology and anthropology.

The sequence alteration associated with a mutational hotspot in p53 protects cells from lysis by cytotoxic T lymphocytes specific for a flanking peptide epitope

A high proportion of tumors arise due to mutation of the p53 tumor suppressor protein. A p53 hotspot mutation at amino acid position 273 from R to H, flanking a peptide epitope that spans residues 264-272, renders cells resistant to killing by human histocompatibility leukocyte antigen (HLA)-A*0201-restricted cytotoxic T lymphocytes (CTLs) specific for this epitope. Acquisition of the R to H mutation at residue 273 of the human p53 protein promotes tumor growth in vivo by selective escape from recognition by p53.264-272 peptide-specific CTLs. Synthetic 27-mer p53 polypeptides covering the antigenic nonamer region 264-272 of p53 were used as proteasome substrates to investigate whether the R to H mutation at the P1' position of the COOH terminus of the epitope affects proteasome-mediated processing of the protein. Analysis of the generated products by tandem mass spectrometry and the kinetics of polypeptide processing in conjunction with CTL assays demonstrate that the R to H mutation alters proteasomal processing of the p53 protein by inhibiting proteolytic cleavage between residues 272 and 273. This prevents the release of the natural CTL epitope that spans flanking residues 264-272 as well as a putative precursor peptide. These results demonstrate that mutation of p53 not only leads to malignant transformation but may also, in some instances, affect immune surveillance and should be considered in the design of cancer vaccines.

Laparoscopy-assisted colonoscopic polypectomy

One of the most feared complications in the removal of moderate-sized or large sessile polyps is colonic perforation. Complete colonoscopic total excision of these kinds of polyps can be safely undertaken using laparoscopic assistance, which enables prompt diagnosis and treatment of perforation. Laparoscopy-assisted endoscopic polyp excision can be safely performed, avoiding critical septic complications and can also help in the selection of patients to appropriate colonic resection without increasing morbidity or mortality.

Laparoscopic transhiatal esophagectomy with esophagogastroplasty

Twelve patients with benign and malignant esophageal diseases were treated by transhiatal esophagectomy, without thoracotomy, using abdominal-mediastinal dissection conducted by videolaparoscopy. A cervical approach was used to retrieve the esophagus and to perform the esophagogastric anastomosis. The procedure was indicated in patients with advanced achalasia of the esophagus, severe reflux stenosis, squamous cell carcinoma, and adenocarcinoma of the esophagus. Three pleural perforations occurred during surgery. Blood loss was minimal. One patient required conversion to open surgery, two patients were submitted to chest drainage, and three had transitory dysphonia. One patient had an anastomotic leak with subsequent stenosis requiring endoscopic dilatation. No mortality occurred in this small series.

DNA image cytometric analysis of differentiated thyroid adenocarcinoma specimens

A total of 117 differentiated thyroid adenocarcinomas that had been removed by total thyroidectomy were studied. Seventy (60%) were papillary, 36 (30%) were follicular, and 11 (10%) were Hürthle cell adenocarcinomas. The mean length of follow-up was 57.7 months. Adverse prognostic factors according to multivariate analysis were adjacent tissue infiltration (p = 0.0004), histologic type (p = 0.0049), and patient age (p = 0.033). The nuclear DNA content of tumor cells and of morphologically normal adjacent tissue was assessed by image cytometry, and correlations between nuclear DNA content and prognostic factors were examined. Fifty-four (75%) adenocarcinomas were classified as aneuploid, 9 (13%) as diploid, and 9 (12%) as borderline. Thirty-four (60%) specimens of morphologically normal adjacent tissue were classified as aneuploid, 18 (32%) as diploid, and 5 (8%) as borderline. The correlation between tumor ploidy and selected prognostic factors was statistically significant for patient age (p = 0.004) and histologic type (p = 0.033). Despite the fact that ploidy could not be identified as a prognostic factor, we suggest that, because of its correlation with age and histologic type, it might prove prognostic if the number of patients were increased. We also emphasize the importance of evaluating morphologically normal adjacent tissue because of the high rates of aneuploidy in these areas.

[Duodenocolonic fistula. Report of a case and review of the literature]

Malignant duodenocolic fistula due to carcinoma of the colon is an infrequent condition. The authors describe a case treated by right hemicolectomy associated with gastrectomy and partial duodenectomy. After a review of the literature, they discuss the surgical possibilities.

[Surgical treatment of acute pancreatitis: experience at a general hospital]

The authors present a study of 15 cases of necrotizing acute pancreatitis treated surgically at the Surgery Department of the University Hospital of the University of São Paulo. All patients in the series were submitted to exploratory laparotomy with sequestrectomy and drainage. Etiology, sex, age, complications, and Ranson prognostic criteria were compared to mortality. Overall mortality was 33%.

[Hemobilia due to chronic cholecystitis. A case report]

The authors report a case of hemobilia in which a fistula was created by corrosion of the cystic artery into the gallbladder. The value of arteriography in diagnosis is emphasized. Cholecystectomy was the definitive treatment.

[Metabolic response and aggression: potassium and water content of skeletal muscles]

The authors present the results of a study of the amount of water and potassium in small samples of skeletal muscle and of the intestinal wall of albino rats. Five groups of 10 animals were separated according to the following conditions: peritonitis, pyloric obstruction, intestinal obstruction, mesenteric ischemia and a control group. The results suggest that skeletal muscle is capable of buffering the increased amount of potassium liberated by the tissues which undergo acute trauma, until a critical concentration is reached. Further studies are needed to clarify some of the conflicting results obtained.