A fluid receiver fitting (FRF) for supporting aseptic fluid transfer between enclosures, as well as methods for forming the fluid receiver, is disclosed. The FRF includes a unitized seal section (226) and channel section (228) formed together by 2-shot injection molding, thereby eliminating or minimizing modes of fluid contamination where the seal section and channel section are separate members. The channel section may comprise one or more channels (286) for insertion of a needle (N) therein and a respective penetration zone (266) in a corresponding section of the seal section for the needle to penetrate and thereby extract a fluid sample from a liquid stream against which a portion of the seal section is exposed. An angled interface (288) between each channel and its corresponding penetration zone provides a liquid stream pressure concentration zone which applies pressure to close a core (C) in the seal section formed by removal of the needle.