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The type I interferon receptor (IFNAR) is composed of two subunits, IFNAR-1 and IFNAR-2, encoding transmembrane polypeptides. IFNAR-2 has a dominant role in ligand binding, but IFNAR-1 contributes to binding affinity and to differential ligand recognition. A panel of five monoclonal antibodies (mAb) to human IFNAR-1 (HuIFNAR-1) was produced and characterized. The reactivity of each mAb toward HuIFNAR-1 on native and transfected cells and in Western blot and ELISA formats was determined. In functional assays, one mAb, EA12, blocked IFN-a2 binding to human cells and interfered with Stat activation and antiviral activity. Epitopes for the mAb were localized to subdomains of the HuIFNAR-1 extracellular domain by differential reactivity of the mAb to a series of human/bovine IFNAR-1 chimeras. The antibody EA12 seems to require native HuIFNAR-1 for reactivity and does not map to a single subdomain, perhaps recognizing an epitope containing noncontiguous sequences in at least two subdomains. In contrast, the epitopes of the non-neutralizing mAb FB2, AA3, and GB8 mapped, respectively, to the first, second, and third subdomains of HuIFNAR-1. The mAb DB2 primarily maps to the fourth subdomain, although its reactivity may be affected by other determinants.

Pregnant farmworkers and those living with farmworkers need to be educated to reduce potential take-home pesticide exposure.

Background: Increased medicalization of childbirth in Mexico has not always translated into more satisfactory childbirth experiences for women. In developed countries, pregnant women often prepare written birth plans, outlining how they would like their childbirth experiences to proceed. The notion of expressing childbirth desires with a birth plan is novel in the developing world. We conducted an exploratory study to assess the feasibility and acceptability of introducing birth plans in a hospital serving low-socioeconomic status Mexicans and to document women's and health practitioners' perspectives on the advantages and barriers in implementing a birth plan program. Methods: We invited 9 pregnant women to prepare birth plans during their antenatal care visits. The women also participated in interviews before and after childbirth. We also conducted in-depth interviews with 4 women who had given birth in the past year, and with 2 nurses, 2 social workers, and 1 physician to learn about their perspectives on the benefits and challenges of implementing a birth plan program. Results: All 9 women who completed a birth plan found the experience highly satisfying, despite the fact that in some cases, their childbirths did not proceed as they had specified in their plans. Interviewed practitioners believed that birth plans could improve the childbirth experience for women and health care practitioners, but facilities often lacked space and financial incentives for birth plan programs. Conclusions: Our findings suggest that birth plans are acceptable and feasible in this study population. Facility administrators would need to commit to provide the physical space and financial incentives necessary to ensure successful implementation. (BIRTH 34:1 March 2007)

Background: Abortion laws are extremely restrictive in Brazil. The knowledge, opinions of abortion laws, and abortion practices of obstetrician-gynecologists can have a significant impact on women's access to safe abortion.

Type I interferons bind to a common receptor (IFNAR), composed of two transmembrane polypeptides, IFNAR-1 and IFNAR-2. Although human IFNAR-1 has a weak intrinsic affinity for human Type I interferons (IFNs), bovine IFNAR-1 binds human Type I IFNs with moderate (nM) affinity, and can be conveniently used to investigate the regions of IFNAR-1 involved in ligand binding. We have constructed 14 bovine/human IFNAR-1 chimeras by exchanging homologous subdomains in the extracellular portion of the receptor. These chimeras were expressed at very high levels on COS cells, and their ability to bind HuIFN-alpha2 was measured. No single bovine subdomain substituted into human IFNAR-1 could confer moderate-affinity ligand binding on the resulting chimera. Simultaneous substitution of bovine IFNAR-1 subdomains 2 and 3 for the homologous human subdomains resulted in a dramatic increase in the binding of IFN-alpha2, suggesting that critical determinants for moderate-affinity ligand binding by BoIFNAR-1 reside in these two subdomains. Bovine subdomains 1 and/or 4 each further enhanced IFN-alpha2 binding in the presence of bovine subdomains 2 and 3. Thus, the binding interactions of BoIFNAR-1 with IFNs appears to be more complex than that of other class II cytokine receptors with their ligands.

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