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HIV-infected older individuals may have a diminished immune response because of exhaustion/immune aging of T-cells. Therefore, we have investigated HIV-specific CD4 and CD8 T-cell responses in 100 HIV-infected patients (HIV + ) who have aged on long-term antiretroviral therapy (ART) and achieved controlled viremia (mostly undetectable viral load; 92 patients with <20 to <40 HIV RNA copies/mL and 8 <60 to <100) and improved CD4 T-cell counts. We show that the median frequencies of HIV-specific CD4 + and CD8 + IFN-γ T-cells were higher in HIV + than uninfected individuals (HIV - ), including increasing levels of IFN-γproduced by CD4 + T-cells and decreasing levels by CD8 + T-cells with increasing CD4 T-cell counts in HIV + . No correlation was found between T-cell responses and varying levels of undetectable viremia. HIV-specific TNF-α made by CD8 + T-cells was higher in HIV + than HIV - , including decreasing levels with increasing CD4 T-cell counts in HIV + . Furthermore, the CD8 + T-cell mediators, CD107a and Granzyme-B, were higher in HIV + than HIV - , and decreased with increasing CD4 T-cell counts in HIV + . Remarkably, HIV-specific CD8 T-cells produced decreasing levels of IFN-γwith increasing age of HIV + , including decreased levels of CD107a and Granzyme-B in older HIV + . However, HIV-specific CD8 + T-cells produced increasing levels of TNF-α with increasing age of the HIV + , suggesting continued inflammation. In conclusion, HIV + with controlled viremia on long-term ART and with higher CD4 T-cell counts showed reduced HIV-specific CD8 T-cell responses as compared to those with lower CD4 T-cell counts, and older HIV + exhibited decreasing levels of CD8 T-cell responses with increasing age.

Dengue, yellow fever, and Zika are viruses transmitted by yellow fever mosquito, Aedes aegypti [Linnaeus (Diptera: Culicidae)], to thousands of people each year. Mosquitoes transmit these viruses while consuming a blood meal that is required for oogenesis. Iron, an essential nutrient from the blood meal, is required for egg development. Mosquitoes receive a high iron load in the meal; although iron can be toxic, these animals have developed mechanisms for dealing with this load. Our previous research has shown iron from the blood meal is absorbed in the gut and transported by ferritin, the main iron transport and storage protein, to the ovaries. We now report the distribution of iron and ferritin in ovarian tissues before blood feeding and 24 and 72 h post-blood meal. Ovarian iron is observed in specific locations. Timing post-blood feeding influences the location and distribution of the ferritin heavy-chain homolog, light-chain homolog 1, and light-chain homolog 2 in ovaries. Understanding iron deposition in ovarian tissues is important to the potential use of interference in iron metabolism as a vector control strategy for reducing mosquito fecundity, decreasing mosquito populations, and thereby reducing transmission rates of vector-borne diseases.

Although many HIV-infected patients have attained older age owing to the success of antiretroviral therapy (ART) in controlling viremia and increasing CD4 T cell counts, HIV continues to persist in several target cells. We have characterized 514 HIV-1 envelope V3 region sequences (94-96 amino acids [aa]) from 25 HIVinfected older patients' peripheral blood mononuclear cell DNA on long-term ART with controlled viremia (undetectable viral load) and improved CD4 T cell counts. Phylogenetic analysis revealed that the V3 region sequences of each patient formed distinct clusters that were well separated and discriminated from other patients' sequences. The coding potential of the V3 region, including several patient-specific amino acid motifs and functional domains, including the two cysteines sandwiching the V3 loop, the central GPGR motif with variation at one position in some sequences, the base GDIR motif, and the N-glycosylation sites were generally conserved. The patients' V3 region sequences contained amino acid motifs conferring affinity mostly for CCR5 coreceptor, suggesting R5 phenotype. There was a low degree of heterogeneity and lower estimates of genetic diversity in all 25 patients' V3 region sequences. Twelve of 25 patients' V3 region sequences were found to be under positive selection pressure. Analysis of the several cytotoxic T lymphocytes (CTL) epitopes showed variation, whereas some of known neutralizing antibodies (nAbs) epitopes showed conservation in patients' V3 region sequences. In conclusion, a low degree of genetic variability and maintenance of functional domains with R5 phenotypes, and variation in CTL and conservation of nAb epitopes were the hallmarks of V3 region sequences from our 25 virologically controlled HIV-infected older patients on long-term ART.

BACKGROUND DNA-and proteomics-based techniques are currently used to identify a triatomine human blood meal. These methods are time consuming, require access to laboratories with sophisticated equipment, and trained personnel. OBJECTIVES We tested a rapid and specific immunochromatographic assay (that detects human blood in forensic samples) to determine if human blood was present in triatomines and their fecal excreta. METHODS We fed Triatoma rubida human blood (positive control) or mouse blood (negative control) and performed the assay on the abdominal contents and fecal excreta. Triatomine field specimens collected in and around human habitations and excreta were also tested. FINDINGS The assay was positive in triatomines fed human blood (N = 5/5) and fecal excreta from bugs known to have ingested human blood (N = 5/5). Bugs feeding on mice (N = 15/15) and their fecal excreta (N = 8/8) were negative for human blood. Human blood was detected in 47% (N = 23/49) triatomines, representing six different species, collected in the field. MAIN CONCLUSIONS The pilot study shows that this rapid and specific test may have applications in triatomine research. Further study is needed to determine the sensitivity of this assay compared to other well-established techniques, such as DNA-and proteomics-based methodologies and the assay's application in the field.

BackgroundBisbee, Arizona is a small mining community established 1880, located 11 miles from the United States–Mexico border with a total population of 5,500 residents. Homes in this town are revealing evidence of colonization by kissing bugs (triatomines), specifically Triatoma recurva, T. rubida, and T. protracta, which are known to harbor the causative agent of Chagas disease, Trypanosoma cruzi.MethodsCommunity members who were bitten by triatomines, provided specimens from their homes, and completed a home evaluation as well as point-of-care testing for Chagas disease (Chagas Detect™ Plus (CDP) Rapid Test, InBiosInternational, Inc.).ResultsTwenty-two individuals from 17 households consented to participate and provided 117 triatomines collected from inside and/or outside their homes (N = 70 T. rubida; N = 36 T. recurva; N = 11 T. protracta). Trypanosoma cruzi DNA was detected by RT-PCR in 25.6% (30/117) of the total triatomines (31.4% (22/70) T. rubida; 18.2% (2/11) T. protracta; 16.6% (6/36) T. recurva). The median age of homes was 91 years. Mean persons per home was 2.2; with 1.0 dog and 0.8 cat per home. Seventy percent of homes used either a swamp cooler or central air conditioning. Only one home had used pesticides in an attempt to exterminate insects. All homeowners reported various wildlife near their home, including javelina, pack rat, rock squirrel, mule deer, and raccoon (Figure 1). Homeowners were asked to correctly identify these triatomines in a photo line-up of similar insects, and 75% of participants made a successful identification of at least one triatomine, 90.9% being able to identify T. recurva. When asked whether they had changed their sleeping patterns due to triatomine bites, 45.5% (10/22) had done so. The same surveyed group rated their frustration with triatomines in their home on scale of 1–10 (10 being the most frustrated) revealing a mean rating of 6.6; with nine individuals rating 10. CDP rapid testing of these participants (N = 22) were all-negative for serological evidence of T. cruzi infection.ConclusionDespite exposure to T. cruzi-positive triatomines among these household residents, some having sustained hundreds of bites throughout the years, we do not have evidence of transmission of Chagas disease. These are preliminary findings and further study is underway.Figure 1.Disclosures All authors: No reported disclosures.

Background: Many HIV-infected individuals have achieved undetectable viral load and increased CD4 T cells counts due to success of antiretroviral therapy (ART). However, HIV continue to persist in resting T cells, monocytes/macrophages and other quiescent cells. Furthermore, HIV-1 vpr accessory gene may play an important role in persistence of HIV in these infected patients. Objectives: Therefore, we characterized the HIV-1 vpr gene from PBMC DNA of 14 HIV-infected older patients on long term ART with mostly undetectable viral load and increase CD4 T cell counts. Methods: Peripheral blood mononuclear cells (PBMC) were isolated from 14 HIV-infected individuals followed by extraction of genomic DNA, amplification of HIV-1 vpr gene by polymerase chain reaction (PCR), cloning of vpr gene in TOPO vector and characterization of correct size recombinant inserts containing vpr genes. An average of 13 clones were sequenced from each patient followed by sequence analysis by bioinformatic tools. Results: Phylogenetic analysis of 182 vpr sequences demonstrated that the vpr sequences of each patient were well separated and discriminated from other patients’ sequences and formed distinct clusters. The vpr sequences showed a low degree of viral heterogeneity and lower estimates of genetic diversity and about half of the patients’ sequences were under positive selection pressure. While the majority of the Vpr deduced amino acid sequences from most patients contained intact open reading frames, several sequences mostly from two patients had stop codons. Numerous patient-specific amino acid motifs and common amino acid motifs were found in deduced Vpr sequences. The functional domains required for Vpr activity, including virion incorporation, nuclear import of pre-integration complex and cell cycle arrest were generally conserved in most of the Vpr sequences. Several of the known cytotoxic T-lymphocytes (CTL) epitopes in Vpr showed variation in our patients’ sequences. Conclusion: In summary, a low degree of genetic variability and conservation of functional domains and variations in CTL epitopes were the features of vpr sequences from the 14 HIV-infected older patients with controlled viremia on long term ART.

Background It has been hypothesized that HIV-1 infection prematurely “ages” individuals phenotypically and immunologically. We measured phenotypic frailty and immune “aging” markers on T-cells of people living with HIV on long term, suppressive anti-retroviral therapy (ART) to determine if there is an association between frailty and immunosenescence. Methods Thirty-seven (37) community-dwelling people living with HIV were measured for frailty using a sensor-based frailty meter that quantifies weakness, slowness, rigidity, and exhaustion. An immunological profile of the patients’ CD4+ and CD8+ T-cell expression of cell surface proteins and cytokines was performed ( n = 20). Results Phenotypic frailty prevalence was 19% (7/37) and correlated weakly with the number of past medical events accrued by the patient (r = 0.34, p = .04). There was no correlation of frailty with age, sex, prior AIDS diagnosis or HIV-1 viral load, or IFN-γ expression by CD4+ or CD8+ T-cells. There were more immune competent (CD28+ CD57−) cells than exhausted/senescent (CD28− CD57+) T cells. Conclusion Frailty in people living with HIV on long term, suppressive ART did not correlate with aging or T cell markers of exhaustion or immunosenescence.