Microfluidic affinity selection of active SARS-CoV-2 virus particles

We report a microfluidic assay to select active severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral particles (VPs), which were defined as intact particles with an accessible angiotensin-converting enzyme 2 receptor binding domain (RBD) on the spike (S) protein, from clinical samples. Affinity selection of SARS-CoV-2 particles was carried out using injection molded microfluidic chips, which allow for high-scale production to accommodate large-scale screening. The microfluidic contained a surface-bound aptamer directed against the virus's S protein RBD to affinity select SARS-CoV-2 VPs. Following selection (~94% recovery), the VPs were released from the chip's surface using a blue light light-emitting diode (89% efficiency). Selected SARS-CoV-2 VP enumeration was carried out using reverse transcription quantitative polymerase chain reaction. The VP selection assay successfully identified healthy donors (clinical specificity = 100%) and 19 of 20 patients with coronavirus disease 2019 (COVID-19) (95% sensitivity). In 15 patients with COVID-19, the presence of active SARS-CoV-2 VPs was found. The chip can be reprogrammed for any VP or exosomes by simply changing the affinity agent.

Meigs syndrome

BACKGROUND

Meigs syndrome is defined by the presence of a benign ovarian tumor, ascites, and pleural effusion (predominantly on the right side). A characteristic sign of Meigs syndrome is the complete disappearance of exudate after surgical resection of the ovarian tumor.

CASE REPORT

We present a case report of a 58-year-old patient admitted for an advanced ovarian tumor with pleural effusion, ascites, and tumor marker elevation typical for ovarian cancer. Cytological examination of ascites and pleural effusion was repeatedly negative for malignancy. Histopathological examination of the bio-psied tissue was concluded as low-grade mesenchymal neoplasia. The second opinion of histopathological examination was concluded as low grade fibroblastic pelvic tumor without the possibility of exact specification. Dia-gnoses of desmoid fibromatosis and low-grade fibromyxiod sarcoma (less likely) were considered. Surgical resection was indicated, and a large tumor with numerous adhesions to the uterus, bladder, and thin loops with a noticeably thickened peritoneum were perioperatively described. Histologically, left ovarian fibroma with productive peritonitis and sanguine-induced ascites was dia-gnosed. Due to the clinical findings and the result of the histopathological examination, the case was classified as Meigs syndrome. Two months after the surgery, the ascites and pleural effusion disappeared, and the tumor marker levels normalized.

CONCLUSION

The present case report documents that it is always necessary to consider diseases other than those most likely at the outset, as the treatment algorithm and prognosis of these rare diseases may differ significantly.

Identification of fetal aneuploidy with dual-probe fluorescence in situ hybridization analysis in circulating trophoblasts after enrichment using a high-sensitivity microfluidic platform

OBJECTIVE

To evaluate a microfluidics-based positive selection technology for isolating circulating trophoblasts (CTs) from peripheral blood of women whose pregnancies are affected by aneuploidy and to evaluate fetal karyotype using fluorescence in situ hybridization (FISH).

METHOD

Ten 18-ml samples of peripheral blood were collected consecutively from pregnant women whose fetus was affected by aneuploidy. A preservation buffer was added, and the specimens were shipped overnight to the testing laboratory at ambient temperature. The specimen was infused into the fully automated microfluidics-based LiquidScan^® instrument without pre-processing. This instrument contains microfluidic chips, which are coated with antibodies (anti-huEpCAM and a proprietary antibody mixture) specific to CT surface epitopes. FISH analysis was performed on the enriched cells.

RESULTS

Fetal aneuploidy evaluated included trisomy 21 (n = 3), trisomy 18 (n = 1), trisomy 13 (n = 1), monosomy X (n = 3), and triploidy (n = 1). CTs for analysis by FISH were identified in all samples. The average number of mononucleate cells per 1 ml of whole blood was 2.11 (range 0.38-4.63) overall and was 2.67 (range 1.13-4.63) using the proprietary combination of antibodies. FISH results were concordant with the aneuploidy based on other testing in all cases. Multinucleate cells were searched for and identified in the last seven samples (average number: 0.84/1 ml).

CONCLUSIONS

Our study demonstrates that the LiquidScan^® , a high-sensitivity microfluidic platform, can enrich circulating trophoblasts (mononucleate and multinucleate). FISH can then be used to detect fetal aneuploidy.