Progress Towards the ELROI\u3csup\u3eTM\u3c/sup\u3e Satellite License Plate

The ELROITM System, (Extremely Low Resource Optical Identifier), uses a beacon that could be attached to any object that goes into space and provide a persistent identifier to the space object that can be read out by a small telescope on the ground. This could alleviate the approaching crisis in Space Traffic Management caused by mass launches of small satellites and the formation of large constellations. Identification beacons on all future space objects will simplify satellite operations and greatly relieve our overstressed space tracking and traffic management infrastructure

Isolation of a Human Anti-HIV gp41 Membrane Proximal Region Neutralizing Antibody by Antigen-Specific Single B Cell Sorting

Broadly neutralizing antibodies are not commonly produced in HIV-1 infected individuals nor by experimental HIV-1 vaccines. When these antibodies do occur, it is important to be able to isolate and characterize them to provide clues for vaccine design. CAP206 is a South African subtype C HIV-1-infected individual previously shown to have broadly neutralizing plasma antibodies targeting the envelope gp41 distal membrane proximal external region (MPER). We have now used a fluoresceinated peptide tetramer antigen with specific cell sorting to isolate a human neutralizing monoclonal antibody (mAb) against the HIV-1 envelope gp41 MPER. The isolated recombinant mAb, CAP206-CH12, utilized a portion of the distal MPER (HXB2 amino acid residues, 673–680) and neutralized a subset of HIV-1 pseudoviruses sensitive to CAP206 plasma antibodies. Interestingly, this mAb was polyreactive and used the same germ-line variable heavy (VH1-69) and variable kappa light chain (VK3-20) gene families as the prototype broadly neutralizing anti-MPER mAb, 4E10 (residues 672–680). These data indicate that there are multiple immunogenic targets in the C-terminus of the MPER of HIV-1 gp41 envelope and suggests that gp41 neutralizing epitopes may interact with a restricted set of naive B cells during HIV-1 infection

HIV-1 specific IgA detected in vaginal secretions of HIV uninfected women participating in a microbicide trial in Southern Africa are primarily directed toward gp120 and gp140 specificities.

CAPRISA, 2014.Abstract available in pdf

A Compact Star-Field Sensor for the Los Alamos Designed 1.5U CubeSat System

The Los Alamos National Laboratory (LANL) has designed a compact star-field sensor (SFS) to provide accurate attitude determination to support the pointing requirements of a deployable high-gain antenna on the LANLdesigned 1.5U CubeSat platform. The SFS hardware was designed and built entirely at LANL with the goal of minimizing the size requirements and unit costs. Attitude determination is accomplished by comparing the SFS imagery to the Tycho-2 catalog located onboard the satellite. A full “Lost in Space” attitude solution, accurate to about an arcminute, is accomplished in under a minute. The SFS is fully reprogrammable on orbit, allowing continued algorithm development after launch. The first two units were launched in November 2016. We will discuss the hardware design, algorithm development, and field tests

The Third-Generation Los Alamos 1.5U CubeSat Attitude Determination and Control System: Design and Initial On-Orbit Results

The 3rd Generation 1.5U CubeSat designed at Los Alamos National Laboratory (LANL) contains a compact 3-axis attitude determination and control system (ADCS) to support the pointing requirements of a deployable high-gain antenna. The hardware and software for the ADCS system were designed and built entirely at LANL with the goal of minimizing the size requirements and unit costs. The satellites employ a combination of magnetometers, sun-vector sensors, solid-state gyroscopes, and a star-field sensor for attitude determination. Attitude actuation is accomplished using either 3 magnetic torque rods or 4 momentum wheels arranged in a pyramid configuration. The on-board ADCS processor runs a real-time operating system that is fully reprogrammable while in orbit. The first two units were launched in November 2016 and both units are currently operating in orbit. We will present the design of the hardware and software systems, pre-launch testing and simulation, and initial on-orbit results

Total and HIV-1-specific IgG and IgA in vaginal secretions do not differ by sampling device or timepoint in the same women.

<p>(A) Dacron swabs, flocked swabs, and Merocel sponges were collected from 5 HIV-1 infected (colored circles) and 5 HIV uninfected (grey triangles) women and the eluate was analyzed for total IgG (left) and total IgA (right). Symbols represent the average of two collection time points spaced one hour apart, for each woman and sampling device. For HIV-1 infected women, colors indicate specific individuals. (B) Samples from the first time point (filled circles) and one hour later (open circles) from the 5 HIV-1 infected women were analyzed for gp41-specific IgG (left) and IgA (right) activity, calculated as antigen-specific mean fluorescence intensity (MFI)/ng ml⁻¹ total IgG or IgA. Colors indicate specific individuals. The box-and-whisker plots represent median, 25^th and 75^th percentiles, and range.</p

HIV-1 exposure elicits anti-Env IgA but not IgG antibodies in the vaginal mucosa.

<p>Vaginal Dacron swabs were collected from 57 HIV seronegative women enrolled in the HPTN 035 microbicide trial and analyzed for IgG (C) and IgA (D–E) binding to the indicated HIV-1 Env antigens. (A) Positive IgG controls. Binding of purified pooled HIV-1⁺ immunoglobulin (HIVIG), 4E10 monoclonal IgG (50 µg/ml), 2F5 monoclonal IgG (16 µg/ml) and swabs from an HIV-1 infected HPTN 035 participant (HIV⁺) in mean fluorescent intensity (MFI). (B) Positive IgA controls. Binding of 7B2 monoclonal IgA (1 µg/ml), b12 monoclonal IgA (20 µg/ml) and 2F5 monoclonal IgA (1 µg/ml) in MFI. Lack of IgA binding from an HIV-1 infected HPTN 035 participant (HIV⁺) is also shown. (C) HIV-1 antigen-specific IgG activity, calculated as antigen-specific MFI/ng ml⁻¹ total IgG, in 57 women participating in HPTN 035. One additional HIV-1 infected HPTN 035 participant (HIV⁺) is also shown. (D) HIV-1 antigen-specific IgA activity, calculated as antigen-specific MFI/ng ml¹ total IgA. For the 57 HPTN 035 women (squares), black symbols signify negative responses and colored symbols signify positive responses, with colors indicating specific women. Samples that did not meet the positivity criteria are displayed at zero for specific activity. One additional HIV-1 infected HPTN 035 participant (HIV⁺) is also shown (open circles). (E) Percentage of the 57 HPTN 035 women with positive IgA binding.</p