ABH-Glycan Microarray Characterizes ABO Subtype Antibodies: Fine Specificity of Immune Tolerance After ABO-Incompatible Transplantation

Organ transplantation from ABO blood group-incompatible (ABOi) donors requires accurate detection, effective removal and subsequent surveillance of antidonor antibodies. Because ABH antigen subtypes are expressed differently in various cells and organs, measurement of antibodies specific for the antigen subtypes in the graft is essential. Erythrocyte agglutination, the century-old assay used clinically, does not discriminate subtype-specific ABO antibodies and provides limited information on antibody isotypes. We designed and created an ABO-glycan microarray and demonstrated the precise assessment of both the presence and, importantly, the absence of donor-specific antibodies in an international study of pediatric heart transplant patients. Specific IgM, IgG, and IgA isotype antibodies to nonself ABH subtypes were detected in control participants and recipients of ABO-compatible transplants. Conversely, in children who received ABOi transplants, antibodies specific for A subtype II and/or B subtype II antigens-the only ABH antigen subtypes expressed in heart tissue-were absent, demonstrating the fine specificity of B cell tolerance to donor/graft blood group antigens. In contrast to the hemagglutination assay, the ABO-glycan microarray allows detailed characterization of donor-specific antibodies necessary for effective transplant management, representing a major step forward in precise ABO antibody detection.

Health protection during the Ebola crisis: the Defence Medical Services approach

This paper is a narrative of the policies, procedures, mitigations and observations of the application of Force Health Protection measures applied by the Ministry of Defence (MOD) for the deployment of military personnel to West Africa as part of the UK contribution to the international response to the Ebola crisis from July 2014 to July 2015. The MOD divided the threat into three risk categories: risk from disease and non-battle injury, Ebola risk for non-clinical duties and Ebola risk for healthcare workers. Overall risk management was directed and monitored by the OP GRITROCK Force Health Protection Board. There were six cases of malaria, four outbreaks of gastrointestinal disease, two needlestick injuries in Ebola-facing healthcare workers, one MOD Ebola case and five non-needlestick, high-risk exposures. This experience reinforces the requirement for the Defence Medical Services to have a high level of organisational competence to advise on Force Health Protection for the MOD.

Multi-Scale Entrainment of Coupled Neuronal Oscillations in Primary Auditory Cortex

Earlier studies demonstrate that when the frequency of rhythmic tone sequences or streams is task relevant, ongoing excitability fluctuations (oscillations) of neuronal ensembles in primary auditory cortex (A1) entrain to stimulation in a frequency dependent way that sharpens frequency tuning. The phase distribution across A1 neuronal ensembles at time points when attended stimuli are predicted to occur reflects the focus of attention along the spectral attribute of auditory stimuli. This study examined how neuronal activity is modulated if only the temporal features of rhythmic stimulus streams are relevant. We presented macaques with auditory clicks arranged in 33 Hz (gamma timescale) quintets, repeated at a 1.6 Hz (delta timescale) rate. Such multi-scale, hierarchically organized temporal structure is characteristic of vocalizations and other natural stimuli. Monkeys were required to detect and respond to deviations in the temporal pattern of gamma quintets. As expected, engagement in the auditory task resulted in the multi-scale entrainment of delta- and gamma-band neuronal oscillations across all of A1. Surprisingly, however, the phase-alignment, and thus, the physiological impact of entrainment differed across the tonotopic map in A1. In the region of 11–16 kHz representation, entrainment most often aligned high excitability oscillatory phases with task-relevant events in the input stream and thus resulted in response enhancement. In the remainder of the A1 sites, entrainment generally resulted in response suppression. Our data indicate that the suppressive effects were due to low excitability phase delta oscillatory entrainment and the phase amplitude coupling of delta and gamma oscillations. Regardless of the phase or frequency, entrainment appeared stronger in left A1, indicative of the hemispheric lateralization of auditory function.

Prevalence of cryptococcal antigenuria at initial HIV diagnosis in KwaZulu-Natal

OBJECTIVES

The World Health Organization (WHO) recommends screening HIV-infected people for cryptococcal antigens to identify cryptococcosis, a major cause of AIDS-related deaths. As the burden of cryptococcosis is unknown in South Africa's KwaZulu-Natal province, we assessed the cryptococcal antigenuria prevalence among newly diagnosed HIV-infected adults there.

METHODS

We conducted a cross-sectional study of newly diagnosed HIV-infected adults who received voluntary HIV testing in an out-patient clinic. Participants provided a urine specimen in a sterile container, and we performed testing with a WHO-endorsed rapid cryptococcal antigen lateral flow assay (Immy Inc., Norman, OK, USA) per the manufacturer's specifications. We assessed cryptococcal antigenuria prevalence among participants with CD4 counts < 200 cells/μL, and stratified results by CD4 count categories.

RESULTS

Among 432 participants, the mean (± standard deviation) age was 36.1 ± 9.9 years and 172 (40%) were female. The overall estimated prevalence of cryptococcal antigenuria was 9.0% [95% confidence interval (CI) 6.5-12.1%]. CD4 counts were available for 319 participants (74%); the median CD4 count was 75 cells/μL [interquartile range (IQR) 34-129 cells/μL]. Participants with a negative cryptococcal antigenuria screening test had a median CD4 count of 79 cells/μL (IQR 36-129 cells/μL), while participants with a positive cryptococcal test had a median CD4 count of 41 cells/μL (IQR 10-112 cells/μL). The estimated prevalence of cryptococcal antigenuria among participants with CD4 counts < 50 cells/μL was 12.5% (95% CI 7.0-20.1%), which was significantly higher than that among participants with CD4 counts of 50-200 cells/μL (4.8%; 95% CI 2.3-8.7%).

CONCLUSIONS

Nearly 1 in 10 newly diagnosed HIV-infected adults with CD4 counts < 200 cells/μL in KwaZulu-Natal had evidence of cryptococcal antigenuria. Point-of-care CD4 count testing and cryptococcal antigen screening may rapidly identify cryptococcosis at the time of HIV diagnosis.

Case ascertainment of heat illness in the British Army: evidence of under-reporting from analysis of Medical and Command notifications, 2009-2013

Background

Heat illness in the Armed Forces is considered preventable. The UK military relies upon dual Command and Medical reporting for case ascertainment, investigation of serious incidents and improvement of preventive practices and policy. This process could be vulnerable to under-reporting.

Objectives

To establish whether heat illness in the British Army has been under-reported, by reviewing concordance of reporting to the Army Incident Notification Cell (AINC) and the Army Health Unit (AHU) and to characterise the burden of heat illness reported by these means.

Methods

Analysis of anonymised reporting databases held by the AHU and AINC, for the period 2009–2013.

Results

565 unique cases of heat illness were identified. Annual concordance of reporting ranged from 9.6% to 16.5%. The overall rate was 13.3%. July was the month with the greatest number of heat illness reports (24.4% of total reporting) and the highest concordance rate (30%). Reports of heat illness from the UK (n=343) exceeded overseas notifications (n=221) and showed better concordance (17.1% vs 12.8%). The annual rate of reported heat illness varied widely, being greater in full-time than reservist personnel (87 vs 23 per100 000) and highest in full-time untrained personnel (223 per100 000).

Conclusions

The risk of heat illness was global, year-round and showed dynamic local variation. Failure to dual-report casualties impaired case ascertainment of heat illness across Command and Medical chains. Current preventive guidance, as applied in training and on operations, should be critically evaluated to ensure that risk of heat illness is reduced as low as possible. Clear procedures for casualty notification and surveillance are required in support of this and should incorporate communication within and between the two reporting chains.