The common marmoset (Callithrix jacchus) has two very similar semenogelin genes as the result of gene conversion

Evaluation of Human Semenogelin Membrane Strip Test for Species Cross-reactivity in Dogs

Semenogelins are proteins originating in the seminal vesicle and are useful markers for the presumptive identification of human semen. Detection of semenogelin can be done with a commercially available membrane test. In this study, a commercially available membrane test for human semenogelin proteins was used to assess for cross-reactivity in dog bodily fluids to allow for the potential utilization for detection of human semen in dog bodily fluids. The authors analyzed canine semen and other bodily fluids, including urine, saliva, vaginal secretions, fecal material, and blood. They also examined the distribution of human semenogelin I transcripts in the canine testis, prostate, and several bodily fluids by reverse transcription polymerase chain reaction. No cross-reactivity was observed in the canine bodily fluids tested except for a single rectal swab, which was negative on a second test. Further testing should be done to validate the use of this kit for screening samples from dogs suspected to have been victims of sexual abuse.

Three genes expressing Kunitz domains in the epididymis are related to genes of WFDC-type protease inhibitors and semen coagulum proteins in spite of lacking similarity between their protein products

Background

We have previously identified a locus on human chromosome 20q13.1, encompassing related genes of postulated WFDC-type protease inhibitors and semen coagulum proteins. Three of the genes with WFDC motif also coded for the Kunitz-type protease inhibitor motif. In this report, we have reinvestigated the locus for homologous genes encoding Kunitz motif only. The identified genes have been analyzed with respect to structure, expression and function.

Results

We identified three novel genes; SPINT3, SPINT4 and SPINT5, and the structure of their transcripts were determined by sequencing of DNA generated by rapid amplification of cDNA ends. Each gene encodes a Kunitz domain preceded by a typical signal peptide sequence, which indicates that the proteins of 7.6, 8.7, and 9.7 kDa are secreted. Analysis of transcripts in 26 tissues showed that the genes predominantly are expressed in the epididymis. The recombinantly produced proteins could not inhibit the amidolytic activity of trypsin, chymotrypsin, plasmin, thrombin, coagulation factor Xa, elastase, urokinase and prostate specific antigen, whereas similarly made bovine pancreatic trypsin inhibitor (BPTI) had the same bioactivity as the protein isolated from bovine pancreas.

Conclusions

The similar organization, chromosomal location and site of expression, suggests that the novel genes are homologous with the genes of WFDC-type protease inhibitors and semen coagulum proteins, despite the lack of similarity in primary structure of their protein products. Their restricted expression to the epididymis suggests that they could be important for male reproduction. The recombinantly produced proteins are presumably bioactive, as demonstrated with similarly made BPTI, but may have a narrower spectrum of inhibition, as indicated by the lacking activity against eight proteases with differing specificity. Another possibility is that they have lost the protease inhibiting properties, which is typical of Kunitz domains, in favor of hitherto unknown functions.

Developmental validation of the SPERM HY-LITER™ kit for the identification of human spermatozoa in forensic samples

With sexual assault evidence, the visualization of spermatozoa confirms that ejaculation has occurred. However, microscopic examination of spermatozoa is a laborious process and can sometimes result in sperm cells being overlooked. Here, we present the developmental validation of the SPERM HY-LITER™ kit, which contains a human sperm-specific mouse monoclonal antibody coupled to a fluorescent Alexa 488 dye. The kit was tested using samples of human semen, saliva, blood, and urine, various animal semen extracts, sexual lubricants, and a commercially available spermicidal film. Postcoital vaginal swabs, degraded semen samples, and samples prepared with sample fixation techniques that deviated from the kit-provided protocol were also tested. In each case, the SPERM HY-LITER™ kit was demonstrated to bind only to human sperm cell heads. Limitations to this fluorescent staining procedure include nonspecific staining and increased background fluorescence with extreme heat fixation in some samples.

Nonhuman primates as models for studies of prostate specific antigen and prostatic diseases

BACKGROUND

Because prostate specific antigen (PSA) is released at increased levels into the blood early in the development of prostate cancer, benign prostatic hyperplasia (BPH) and prostatitis, it is widely used as a marker for these diseases. However, PSA has clinical limitations as a screen for prostatic diseases due to its low sensitivity and specificity. There is a strong need to better understand the biology of PSA and factors affecting its serum levels.

METHODS

We evaluated cynomolgus macaques, rhesus macaques, baboons, and marmosets for their suitability as models for the study of PSA biology and prostatic diseases.

RESULTS

Prostates of several nonhuman primates are anatomically similar to the human counterpart. Anti-human PSA antibody detected PSA antigens in all the Old World monkeys (cynomolgus macaques, rhesus macaques, and baboons) but not in marmosets. Of the Old World monkeys, cynomolgus macaques have the highest serum PSA levels; baboons have the lowest. Serum PSA levels from macaques includes a number of outlier samples with unusually high values. We also report two cases of abnormal pathologies in macaques accompanied by high serum PSA levels. One case consisted of prostatic hyperplasia involving both glandular and basal cells in a cynomolgus macaque and another of glandular hyperplasia and atrophy in a rhesus macaque. The finding that pathological changes in the prostate of macaques may lead to increases in serum PSA is worthy of further exploration.

CONCLUSION

Cynomolgus macaques and rhesus macaques are promising animal models for PSA biology studies.