Brief Report: Safety and Tolerability of Inguinal Lymph Node Biopsy in Individuals With Acute HIV Infection in Thailand

Safety and practicality of an excisional lymph node study driving HIV cure research in South Africa

Introduction

Studying diseased human tissues offers better insights into the intricate interactions between pathogens and the human host. In conditions such as HIV and cancers, where diseases primarily manifest in tissues, peripheral blood studies are limited in providing a thorough understanding of disease processes and localized immune responses.

Methods

We describe a study designed to obtain excisional lymph nodes from volunteers for HIV reservoir studies. Since study commencement in 2015, 181 lymph node excisions have been performed, resulting in collection of 138 lymph node tissues. Lymph nodes were surgically excised from study volunteers using a minimally invasive procedure, performed in a minor theater under local anesthesia.

Results

The surgery takes less than 30 minutes to complete, minimizing risk and stress on the volunteer. The small incision made during the procedure typically heals within a week. The associated discomfort is generally manageable, and participants are often able to resume their regular activities within a day. Only 5.5% of the study participants experienced minor adverse events, such as swelling and prolonged wound healing, recovering within 2 weeks with no serious adverse events reported.

Discussion

Our study demonstrates that when done with outmost care, obtaining excised lymph nodes for research is relatively safe and practical.

Decision making for invasive and non-invasive optional procedures within an acute HIV research cohort in Bangkok

Clinical research regularly includes required, nontherapeutic procedures to answer research questions. Optional procedures usually offer minimal or no personal benefit and may involve harms and burdens. Members from the Bangkok SEARCH010/RV254 HIV research cohort of individuals acutely HIV-infected are recruited to six optional procedures varying in invasiveness: leukapheresis, genital secretions collection, lumbar puncture, brain MRI/MRS/DTI, colon biopsy, and lymph node biopsy. We surveyed cohort members about their first recruitment for each procedure to examine factors associated with decision making and attitudes about compensation. 406 members (68%) completed the survey. Reported procedure participation ranged from 71% (MRI) to 27% (lymph node biopsy). Respondents underwent 0-6 procedure types (median 3). Ordinal regression indicated that lower perceived HIV impact and HIV remission trial participation were associated with more procedures completed. Reports of decision difficulty varied, and feeling pressured by research staff was low overall. Notably, those who declined procedures and those who underwent more invasive procedures reported greater decision difficulty and perceived pressure. Most respondents felt compensation amounts were appropriate, although opinions differed by procedure, and for some procedures, between people who agreed and declined. There is limited literature regarding consent to and attitudes about optional research procedures. Researchers must consider how to best support voluntary decisions for procedures with little personal benefit, particularly in lower-income or marginalized populations. In this longitudinal research cohort, perceived pressure to participate may be a concern, although our finding of variation in participation rates corresponding to invasiveness is reassuring. Data from different research contexts would provide important comparators.

CD8 lymphocytes mitigate HIV-1 persistence in lymph node follicular helper T cells during hyperacute-treated infection

HIV persistence in tissue sites despite ART is a major barrier to HIV cure. Detailed studies of HIV-infected cells and immune responses in native lymph node tissue environment is critical for gaining insight into immune mechanisms impacting HIV persistence and clearance in tissue sanctuary sites. We compared HIV persistence and HIV-specific T cell responses in lymph node biopsies obtained from 14 individuals who initiated therapy in Fiebig stages I/II, 5 persons treated in Fiebig stages III-V and 17 late treated individuals who initiated ART in Fiebig VI and beyond. Using multicolor immunofluorescence staining and in situ hybridization, we detect HIV RNA and/or protein in 12 of 14 Fiebig I/II treated persons on suppressive therapy for 1 to 55 months, and in late treated persons with persistent antigens. CXCR3+ T follicular helper cells harbor the greatest amounts of gag mRNA transcripts. Notably, HIV-specific CD8+ T cells responses are associated with lower HIV antigen burden, suggesting that these responses may contribute to HIV suppression in lymph nodes during therapy. These results reveal HIV persistence despite the initiation of ART in hyperacute infection and highlight the contribution of virus-specific responses to HIV suppression in tissue sanctuaries during suppressive ART.

Antimicrobial prophylaxis does not improve post-surgical outcomes in SIV/SHIV-uninfected or SIV/SHIV-infected macaques (Macaca mulatta and Macaca fascicularis) based on a retrospective analysis

Surgical antimicrobial prophylaxis is indicated when performing contaminated surgeries, when specific surgical implants are placed, and for prolonged surgical procedures. Unnecessary prophylactic antibiotics are often utilized for macaque surgeries, despite medical and veterinary guidelines. In this study we compared complication rates in macaques receiving peripheral lymph node (PLN) and laparoscopic biopsies, with and without antimicrobial prophylaxis. A majority of animals were SIV or SHIV infected at the time of surgery, so we also compared post-operative complication rates based on infection status. We found no significant difference in PLN biopsy complication rates for animals that received antimicrobial prophylaxis versus those that did not. Animals who underwent laparoscopic procedures and received prophylactic antibiotics had a higher complication rate than those who did not receive them. Complication rates did not differ significantly for SIV/SHIV infected versus uninfected animals for both laparoscopic biopsy procedures and PLN biopsy procedures. SIV/SHIV infected animals that underwent PLN biopsies had no significant difference in complication rates with and without antimicrobial prophylaxis, and SIV/SHIV infected animals receiving prophylactic antibiotics for laparoscopic biopsies had a higher complication rate than those that did not. This study suggests that perioperative prophylactic antibiotics have no role in the management of SIV/SHIV-infected and uninfected macaques undergoing clean, minimally invasive surgeries. Additionally, we recommend eliminating unnecessary antibiotic use in study animals due to their potential confounding impacts on research models and their potential to promote antimicrobial resistance.

Normal human lymph node T follicular helper cells and germinal center B cells accessed via fine needle aspirations

Germinal centers (GC) are critically important for maturation of the antibody response and generation of memory B cells, processes that form the basis for long-term protection from pathogens. GCs only occur in lymphoid tissue, such as lymph nodes, and are not present in blood. Therefore, GC B cells and GC T follicular helper (T_FH) cells are not well-studied in humans under normal healthy conditions, due to the limited availability of healthy lymph node samples. We used a minimally invasive, routine clinical procedure, lymph node fine needle aspirations (LN FNAs), to obtain LN cells from healthy human subjects. This study of 73 LNs demonstrates that human LN FNAs are a safe and feasible technique for immunological research, and suggests benchmarks for human GC biology under noninflammatory conditions. The findings indicate that assessment of the GC response via LN FNAs will have application to the study of human vaccination, allergy, and autoimmune disease.

A landscape analysis of HIV cure-related clinical trials and observational studies in 2018

OBJECTIVES

The community-based organisation Treatment Action Group has established an online listing of HIV cure-related trials and observational studies derived from trial registries. Our objective was to use the listing as a basis for a landscape analysis of the current status of HIV cure-related clinical research.

METHODS

Trials and observational studies listed as of August 2018 formed the sample set. Survey questions were developed on trial development, trial design, recruitment, enrolment, study completion and dissemination plans. A survey was sent to the contact(s) for each study. Supplemental information was collected from clinicaltrials.gov. The full dataset was then analysed.

RESULTS

A total of 99 interventional trials and 29 observational studies were included. Diverse interventions are under evaluation, including combinations of experimental candidates. Current studies plan to enrol over 7000 participants. Projected completion dates for ~90% of the sample fell between the fourth quarter of 2018 and the end of 2020. Potential obstacles to enrolment that were reported included concerns over invasive procedures and lack of potential benefit to participants. Data on the sex and ethnicity of enrollees were limited but sufficient to note a significant under-representation of women.

CONCLUSIONS

A considerable amount of HIV cure-related clinical research is under way. The results from these studies, which should help shape the future of the field, will become available over the next 2-4 years. Diversity both geographically and in terms of enrollees remains limited, particularly in terms of the participation of women, a concern that could significantly affect the generalisability of the findings.

Leveraging early HIV diagnosis and treatment in Thailand to conduct HIV cure research

Thailand has the highest prevalence of HIV among countries in Asia but has also been a pioneer in HIV prevention and treatment efforts in the region, reducing the incidence of new infections significantly over the last two decades. Building upon this remarkable history, Thailand has set an ambitious goal to stop the AIDS epidemic in the country by 2030. A key component of the strategy to achieve this goal includes scale-up of HIV screening programs to facilitate early HIV diagnosis and investment in mechanisms to support immediate initiation of antiretroviral therapy (ART). Initiation of ART during early or acute HIV infection not only reduces viremia, thereby halting onward transmission of HIV, but also may facilitate HIV remission by reducing the size of the latent HIV reservoir and preserving immune function. In Thailand, many efforts have been made to reduce the time from HIV infection to diagnosis and from diagnosis to treatment, especially among men who have sex with men and transgender women. Successfully identifying and initiating ART in individuals with acute HIV infection has been leveraged to conduct groundbreaking studies of novel strategies to achieve HIV remission, including studies of broadly-neutralizing HIV-specific monoclonal antibodies and candidate therapeutic vaccines. These efforts have mostly been deployed in Bangkok and future efforts should include other urban and more rural areas. Continued progress in HIV prevention, screening, and treatment will position Thailand to substantially limit new infections and may pave the way for an HIV cure.

Safety and tolerance of lymph node biopsies from chronic HIV-1 volunteers in rural Tanzania

Objective

HIV-1 rapidly establishes a persistent infection that can be contained under life-long antiretroviral therapy (ART) but not cured. One major viral reservoir is the peripheral lymph node (LN) follicles. Studying the impact of novel HIV-1 treatment and vaccination approaches on cells residing in germinal centers is essential for rapid progress towards HIV-1 prevention and cure.

Results

We enrolled 9 asymptomatic adult volunteers with a newly diagnosed HIV-1 infection and CD4 T cell counts ≥ 350/ml. The patients underwent venous blood collection and inguinal lymph node excision surgery in parallel. Mononuclear cells were extracted from blood and tissues simultaneously. Participants were followed up regularly for 2 weeks until complete healing of the surgical wounds. All participants completed the lymph node excision surgery without clinical complications. Among the 9 volunteers, one elite controller was identified. The number of mononuclear cells recovered from lymph nodes ranged from 68 to 206 million and correlated positively with lymph node size. This is the first study to show that lymph node biopsy is a safe procedure and can be undertaken with local experts in rural settings. It provides a foundation for detailed immune response investigations during future clinical trials.