Identification of mouse CD4+ T cell epitopes in SARS-CoV-2 BA.1 spike and nucleocapsid for use in peptide:MHCII tetramers

Understanding adaptive immunity against SARS-CoV-2 is a major requisite for the development of effective vaccines and treatments for COVID-19. CD4+ T cells play an integral role in this process primarily by generating antiviral cytokines and providing help to antibody-producing B cells. To empower detailed studies of SARS-CoV-2-specific CD4+ T cell responses in mouse models, we comprehensively mapped I-Ab-restricted epitopes for the spike and nucleocapsid proteins of the BA.1 variant of concern via IFNγ ELISpot assay. This was followed by the generation of corresponding peptide:MHCII tetramer reagents to directly stain epitope-specific T cells. Using this rigorous validation strategy, we identified 6 immunogenic epitopes in spike and 3 in nucleocapsid, all of which are conserved in the ancestral Wuhan strain. We also validated a previously identified epitope from Wuhan that is absent in BA.1. These epitopes and tetramers will be invaluable tools for SARS-CoV-2 antigen-specific CD4+ T cell studies in mice.

Antenatal Ultrasound Detection of Cleft in Western Australia from 2003 to 2012: A Follow-Up Study

AIM

To investigate trends in the rate of antenatal detection of cleft lip and palate (CLP) patients referred to the CLP Unit at Princess Margaret Hospital for Children in Perth, Western Australia during the period 2003-2012 and compare data with a previously published report covering the years 1996-2003.

METHODS

This is a single-center, retrospective survey of antenatal transabdominal ultrasound screenings of mothers of infants born between July 1, 2003 and June 30, 2012 that were referred to the CLP Unit at Princess Margaret Hospital.

RESULTS

Detection rates of oral clefts increased significantly when compared with outcomes reported in the same population between 1996 and 2003 (P < .05). An overall detection rate of 71.7% (165/230) was achieved for clefts involving lip and palate. Detection of isolated cleft palate (1/99) and microform (0/8) remained elusive. Most detections (76.5%) were achieved at 15 to 20 weeks of gestational age, corresponding with routine anatomical screening. A further 16.8% were detected post-20 weeks of gestation. Scans were performed by specialist obstetricians, and sonography clinics reported a detection rate of 84.6% (55/65), whereas nonspecialist clinics reported a detection rate of only 67.1% (110/164).

CONCLUSION

The antenatal detection rates of oral clefts involving the lip have improved to the extent that the majority of mothers are now being referred to a cleft unit in Western Australia prior to the births of their children. As a result of this improvement, antenatal counseling is now a common facet of cleft management.

Incidence of acquired CNS demyelinating syndromes in a multiethnic cohort of children

OBJECTIVE

To determine whether the incidence and clinical features of pediatric multiple sclerosis (MS) and other forms of pediatric acquired demyelinating syndromes (ADS) vary by race/ethnicity in a population-based cohort.

METHODS

We used a combination of electronic database searches followed by complete medical records review to identify all children diagnosed with MS and ADS in the multiethnic membership of Kaiser Permanente Southern California from January 1, 2004, to December 31, 2009. Incidence rates were standardized to the US census by age and gender.

RESULTS

We identified 81 incident cases of ADS from 4.87 million person-years of observation in children 0-18 years of age. The incidence rate of pediatric MS was 0.51 per 100,000 person-years (95% confidence interval [CI] 0.33-0.75) and incidence of other forms of ADS including optic neuritis, transverse myelitis, other forms of clinically isolated syndrome (CIS), and acute disseminated encephalomyelitis (ADEM) was 1.56 (95% CI 1.23-1.95) for an overall incidence of ADS of 1.66 per 100,000 person-years (95% CI 1.32-2.06). Incidence of ADS was higher in black (4.4 per 100,000 person-years, 95% CI 2.5-7.2, p < 0.001) and Asian/Pacific Islander (2.8, 95% CI 1.2-5.2, p = 0.02) than white (1.03, 95% CI 0.6-1.7) and Hispanic (1.5, 95% CI 1.1-2.1, per 100,000 person-years) children. Black children were also significantly more likely to have MS than white children (p = 0.001). Children who presented with ADEM were significantly younger than children with other types of ADS clinical presentations (mean age 5.6, range 0.7-17.6 years vs 14.6, range 2.7-18.5, respectively).

CONCLUSIONS

The incidence of pediatric acquired demyelinating syndromes is 1.66 per 100,000 person-years in a population-based cohort of Southern Californian children. The incidence of ADS and MS is higher in black children compared with white and Hispanic children.

Assessment of the proximal femoral morphology using plain radiograph-can it predict the bone quality?

We evaluated the relationship between the radiological indices that assessed the proximal femoral morphology and the degree of osteoporosis in 45 Chinese cadaveric femora. Canal-calcar ratio, canal flare index, morphological cortical index, and canal bone ratio were determined in the plain anteroposterior radiographs. Canal bone ratio is the ratio between the endosteal and outer diameters of the proximal femur at 10 cm below the lesser trochanter. Bone mineral density of the proximal femora was measured with dual-energy x-ray absorptiometry, and T score that depicted the degree of osteoporosis was determined. Canal bone ratio showed a strong correlation with the T score (r = -0.71, P < .001) and the best overall performance in diagnosing osteoporosis with receiver operating characteristic curve analysis. The proximal femur was likely to be osteoporotic if the canal bone ratio was 0.49 or higher.

Primary actinomycosis mimicking urachal carcinoma

We report a case of urachal actinomycosis that presented with a progressively enlarging infraumbilical mass associated with umbilical discharge. Computed tomography revealed an extraperitoneal mass involving the dome of the bladder. The possible diagnosis included a malignant urachal neoplasm or chronic inflammatory mass. Partial cystectomy and excision of the mass was performed. The pathologic examination revealed actinomycosis. The patient was treated with a 6-month course of antibiotics. No recurrence was noted 1 year postoperatively.