FSH dose to stimulate different patient' ages: when less is more.

OBJECTIVE: To determine the effect of FSH doses on intracytoplasmic sperm injection (ICSI) outcomes according to the age of the patient. METHODS: Patients undergoing controlled ovarian stimulation (COS) for ICSI cycles in a university-affiliated in vitro fertilization center were split into age groups: ≤35 y.o. (n=1523); >35 and ≤38 y.o. (n=652); >38 and ≤40 y.o. (n=332); and >40 y.o. (n=370). The effect of FSH dose on COS, laboratorial and clinical outomes was determined by linear regression models. RESULTS: The FSH dose didn't affect the ovarian response in terms of total number of follicles, retrieved oocytes and mature oocytes within the age groups, but we found that the lower the age, the lower the FSH dose needed per oocyte retrieved. In the group of patients ≤35 y.o., we also found a positive effect of the FSH dose on oocyte yield. Despite that, for patients ≤38 y.o. there was a negative effect of the FSH dose on embryo quality and blastocyst formation rate, and an increase in the cycle's cancelation rate. In patients ≥39 y.o., there were no effects of the FSH doses on the analysed variables. CONCLUSIONS: Ovarian stimulation with high doses of FSH is not recommended in younger women (≤38 y.o.), once we found a decrease in embryo quality and an increase in cycle's cancelation rate. Mild ovarian stimulation protocols may be more appropriate; however, it may not be applicable for women in advanced age, since a higher FSH dose is needed for oocyte retrieval in these patients.

Preventive DNA vaccination against CEA-expressing tumors with anti-idiotypic scFv6.C4 DNA in CEA-expressing transgenic mice.

Carcinoembryonic antigen (CEA) is expressed during embryonic life and in low level during adult life. Consequently, the CEA is recognized by the immune system as a self-antigen and thus CEA-expressing tumors are tolerated. Previously, we constructed a single chain variable fragment using the 6.C4 (scFv6.C4) hybridoma cell line, which gave rise to antibodies able to recognize CEA when C57/Bl6 mice were immunized. Here, the scFv6.C4 ability to prevent the CEA-expressing tumor growth was assessed in CEA-expressing transgenic mice CEA2682. CEA2682 mice immunized with the scFv6.C4 expressing plasmid vector (uP/PS-scFv6.C4) by electroporation gave rise to the CEA-specific AB3 antibody after the third immunization. Sera from immunized mice reacted with CEA-expressing human colorectal cell lines CO112, HCT-8, and LISP-1, as well as with murine melanoma B16F10 cells expressing CEA (B16F10-CEA). Cytotoxic T lymphocytes (CTL) from uP/PS-scFv6.C4 immunized mice lysed B16F10-CEA (56.7%) and B16F10 expressing scFv6.C4 (B16F10-scFv6.C4) (46.7%) cells, against CTL from uP-immunized mice (10%). After the last immunization, 5 × 105 B16F10-CEA cells were injected into the left flank. All mice immunized with the uP empty vector died within 40 days, but uP/PS-scFv6.C4 vaccinated mice (40%) remained free of tumor for more than 100 days. Splenocytes obtained from uP/PS-scFv6.C4 vaccinated mice showed higher T-cell proliferative activity than those from uP vaccinated mice. Collectively, DNA vaccination with the uP-PS/scFv6.C4 plasmid vector was able to give rise to specific humoral and cellular responses, which were sufficient to retard growth and/or eliminate the injected B16F10-CEA cells.

QCM immunoassay for recombinant cysteine peptidase: a potential protein biomarker for diagnosis of citrus canker.

Citrus canker is one of the most important agricultural citrus diseases worldwide. It is caused by Xanthomonas citri subsp. citri (Xcc) bacterium that infects leaves and the fruits produce a cysteine peptidase (CPXaC), which makes it a potential target for the development of effective and rapid detection methods for citrus canker. We report here the studies on the development of piezoelectric immunoassay for CPXaC using a polyclonal antibody against CPXaC (anti-CPXaC). Three different strategies for covalent immobilization of anti-CPXaC on gold surfaces were evaluated by monitoring the frequency (Δf) and energy dissipation (ΔD) variation in real time when 64.5×10(-8) mol L(-1) CPXaC was added. Anti-CPXaC immobilized with 11-mercaptoundecanoic acid (MUA) showed the best relation between the frequency and dissipation factor variation, and strong values for the kinetic and equilibrium binding constant were obtained. The immunosensor showed a detection limit of 13.0 nmol L(-1) with excellent specificity, showing no response for different proteins that include another cysteine peptidase that is used as a target to detect Xylella fastidiosa bacterium, responsible for another important citrus disease. These results provide good perspectives for the use of CPXaC as a new biomarker for citrus canker.