Detection of human immunodeficiency virus, hepatitis B virus, and hepatitis C virus in donor eyes using polymerase chain reaction

Maximize Donor Cornea Use in a Hepatitis B Endemic Area via Serology Matching

BACKGROUND

This study aims to investigate the rationality of the allocation guidelines in a hepatitis B endemic area that uses corneas from hepatitis B donors.

METHODS

Under Taiwan's current guidelines, corneas donated from hepatitis B surface antigen (HBsAg)(+) donors can be allocated to HBsAg(+) or hepatitis B surface antibody recipients. From January 1, 2015, to December 31, 2019, corneas donated to National Taiwan University Hospital were divided into HBsAg(+), HBsAg(-)/hepatitis B core antibody (anti-HBc)(+), and HBsAg(-)/anti-HBc(-) groups. Hepatitis B virus (HBV) DNA extracted from corneoscleral rims was quantified by polymerase chain reaction and correlated with donor serum HBsAg, anti-HBc, and HBV DNA. Recipients of HBV DNA(+) grafts were called back for serology and serum HBV DNA tests.

RESULTS

The corneoscleral HBV DNA of 170 corneas (113 donors) was quantified, of which 45 corneas were from 28 HBsAg(+) donors, 87 were from 57 HBsAg(-)/anti-HBc(+) donors, and 38 were from 28 HBsAg(-)/anti-HBc(-) donors, and HBV DNA was detected in 80.0%, 9.2%, and 0% of the corneoscleral rims in each group. Donor anti-HBc(+) provided the highest sensitivity (1.00) and negative predictive value (1.00) for corneoscleral HBV DNA. Twenty-eight of 40 recipients (70%) using HBV DNA(+) grafts were called back, and none developed hepatitis in follow-up periods ranging from 6 to 55.5 mo.

CONCLUSIONS

Donor anti-HBc should be tested routinely with HBsAg. Allocating corneas from HBsAg(+) or anti-HBc(+) donors to HBsAg(+) or hepatitis B surface antibody recipients maximizes cornea usage from hepatitis B donors without compromising transplant safety in a hepatitis B endemic setting.

Detection of feline leukaemia virus in blood and bone marrow of cats with varying suspicion of latent infection

The purpose of this study was to determine if polymerase chain reaction (PCR) could be used to detect FeLV proviral DNA in bone marrow samples of cats with varying suspicion of latent infection. Blood and bone marrow samples from 50 cats and bone marrow from one fetus were collected, including 16 cats with diseases suspected to be FeLV-associated. Serum enzyme-linked immunosorbent assay (ELISA), blood and bone marrow immunofluorescent antibody test (IFA), and blood and bone marrow PCR were performed on each cat, and IFA and PCR on bone marrow of the fetus. Forty-one cats were FeLV negative. Five cats and one fetus were persistently infected with FeLV. Four cats had discordant test results. No cats were positive on bone marrow PCR only. It appears persistent or latent FeLV infection is not always present in conditions classically associated with FeLV.

Feline leukemia virus detection in corneal tissues of cats by polymerase chain reaction and immunohistochemistry

OBJECTIVES

To determine the presence of feline leukemia virus (FeLV) in the corneas of FeLV-infected cats.

ANIMALS STUDIED

Thirty-four random source cats.

PROCEDURES

Seventeen cats were found positive for FeLV serum p27 antigen by enzyme-linked immunosorbent assay (ELISA). Twelve ELISA positive cats were also positive on peripheral blood samples by immunofluorescent antibody (IFA) testing. Seventeen ELISA negative cats served as negative controls. Full thickness corneal specimens were collected from the left cornea of all cats and analyzed for FeLV proviral DNA and gp70 antigen by polymerase chain reaction (PCR) and immunohistochemical (IHC) testing, respectively.

RESULTS

Eleven (64.7%) positive corneal PCR results were obtained from 17 ELISA positive cats. Of 12 cats that were both ELISA and IFA positive on peripheral blood, 10 (83.3%) had positive corneal PCR results. All corneal tissues from ELISA negative cats were PCR negative. IHC staining of corneal sections revealed the presence of FeLV gp70 in corneal tissues of nine (52.9%) ELISA positive cats. Of the 12 cats that were both ELISA and IFA positive on peripheral blood, eight (66.7%) had positive corneal IHC results. Positive IHC staining was localized to the corneal epithelium. Corneal tissues of all ELISA negative cats and all IFA negative cats were negative on IHC testing.

CONCLUSIONS

FeLV antigens and proviral DNA are present in corneal tissues of some FeLV-infected cats. Screening corneal donors for FeLV infection is warranted.

Father-to-mother-to-infant transmission of HIV-1: clonally transmitted isolate of infant mutates more rapidly than that of the mother and rapidly loses reactivity with neutralizing antibody

The sequences of the V3 loop and surrounding regions of human immunodeficiency virus type-1 from a father-to-mother-to-infant trimmer were studied and the horizontal and vertical transmissions compared. The father's virus was variable for reactivity with neutralizing antibody and sequences of the V3 loop central core sequence. In contrast, the mother's viral sequences were much less diverse and reacted with a virus neutralizing antibody. The infant's viral sequences were also less diverse than those of the father, and N-glycosylation sites were conserved. By phylogenetic analysis, the major clone, of which V3-peptide reacted with the neutralizing antibody, was found to be transmitted from the mother to her infant; however, the mutated minor clones did not bind to the antibody. These findings suggest that both horizontal and vertical virus transmission were selective, and that the clonally transmitted virus in infants mutates more rapidly than viruses in the mother, to whom the virus was horizontally transmitted.