An antibody targeting the N-terminal domain of SARS-CoV-2 disrupts the spike trimer

The protective human antibody response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) focuses on the spike (S) protein, which decorates the virion surface and mediates cell binding and entry. Most SARS-CoV-2 protective antibodies target the receptor-binding domain or a single dominant epitope (“supersite”) on the N-terminal domain (NTD). Using the single B cell technology called linking B cell receptor to antigen specificity through sequencing (LIBRA-Seq), we isolated a large panel of NTD-reactive and SARS-CoV-2–neutralizing antibodies from an individual who had recovered from COVID-19. We found that neutralizing antibodies against the NTD supersite were commonly encoded by the IGHV1-24 gene, forming a genetic cluster representing a public B cell clonotype. However, we also discovered a rare human antibody, COV2-3434, that recognizes a site of vulnerability on the SARS-CoV-2 S protein in the trimer interface (TI) and possesses a distinct class of functional activity. COV2-3434 disrupted the integrity of S protein trimers, inhibited the cell-to-cell spread of the virus in culture, and conferred protection in human angiotensin-converting enzyme 2–transgenic (ACE2-transgenic) mice against the SARS-CoV-2 challenge. This study provides insight into antibody targeting of the S protein TI region, suggesting this region may be a site of virus vulnerability.     

Base of tongue schwannoma: a case report

Both malignant and benign lesions may be found on the base of the tongue, including metastasis from other sites. Various surgical approaches to the base of tongue have been described. Here, we report a case of a 26-year-old woman with a schwannoma in the base of tongue removed through a suprahyoid pharyngotomy approach. The biology and pathology of schwannoma in the oral cavity are discussed. The advantage of the suprahyoid pharyngotomy approach for complete excision of a mass in the base of tongue is demonstrated.     

Utility of screening for other causes of infertility in women with "known" polycystic ovary syndrome

We investigated the prevalence of abnormal screening results (questionnaire and testing for other causes of oligo-ovulation, male or tubal factor infertility) in a group of 1,313 oligo-ovulatory women (included and excluded subjects) whose condition was screened for inclusion in the Pregnancy in Polycystic Ovary Syndrome trial, a multicenter clinical trial that was conducted at 13 sites in the United States. Other than failure to demonstrate laboratory evidence of hyperandrogenemia, the most common reasons for subject exclusion were persistent oligospermia and tubal factor infertility.     

Evaluation of the herpes simplex virus antiviral activity of pyrethrins

Pyrethrins, complex esters extracted from Chrysanthemum cinerariaefolium, exhibit only minimal in vitro activity against herpes simplex virus (HSV). Employing a guinea pig model of HSV genital infection, no in vivo activity could be demonstrated. Although purported to be an effective remedy for the treatment of genital herpes, we were unable to demonstrate efficacy for either the oral administration of an alcoholic solution of pyrethrins or the topical application of pyrethrins in mineral oil.