The rN proteins in this study had the expected sizes as observed by immunoblotting with N-specific MAbs raised against PUUV. to PUUV rN than DOBV rN. Humoral and cellular immune responses after rN immunization were also investigated. WNT-4 The highest cross-reactive humoral responses against PUUV antigen were detected in sera Vipadenant (BIIB-014) from ANDV rN-immunized animals, followed by those from TOPV rN-immunized animals, and only very low antibody cross-reactivity was observed in sera from DOBV rN-immunized animals. In proliferation assays, T lymphocytes from animals immunized with all heterologous rNs were as efficiently recalled in vitro by PUUV rN as were T lymphocytes from animals immunized with homologous protein. In summary, this study has shown that hantavirus N can elicit cross-protective immune responses against PUUV, and the results suggest a more important role for the cellular arm of the immune response than for the humoral arm in cross-protection elicited by rN. Viruses belonging to the genus cells. The open reading frames (ORF) of the PUUV/Kazan (GenBank accession number “type”:”entrez-nucleotide”,”attrs”:”text”:”Z84204″,”term_id”:”2578447″,”term_text”:”Z84204″Z84204), TOPV/Ls136V5/94 (“type”:”entrez-nucleotide”,”attrs”:”text”:”AJ011646″,”term_id”:”4757105″,”term_text”:”AJ011646″AJ011646), DOBV/Slovenia (“type”:”entrez-nucleotide”,”attrs”:”text”:”L41916″,”term_id”:”2981636″,”term_text”:”L41916″L41916), and ANDV (“type”:”entrez-nucleotide”,”attrs”:”text”:”AF004660″,”term_id”:”2352476″,”term_text”:”AF004660″AF004660) N protein-encoding genes have been cloned and sequenced previously (4, 22, 24, 39). The primers utilized for PCR amplification from cDNA were as follows: for PUUV, SPUUV/PQF (5-TTG CAT GCT TAT GAG TGA CTT GAC AGA CAT CCA A-3) (forward) and SPUUV/PQR (5-TTG TCG Take action TAA TCA TAT CTT TAA GGG CTC CTG-3) (reverse); for TOPV, STOP/PQF (5-TAT AAG CAT GCT GAG CAA CCT CAA AGA CAT-3) (forward) and STOP/PQR (5-TAT AAG TCG ACC TAT ATT TTG AGT GGC TCTT-3) (reverse); and for DOBV, SDOB/PQF (5-TAT AAG CAT GCT GGC AAC Take action AGA GGA Take action-3) (forward) and SDOB/PQR (5-TAT AAG TCG Take action TAA AGC TTG AGC GGC TCCT-3) (reverse). All forward and reverse primers contained an with the following antigen:((9)34,836 (6,400-102,400)2,963 ( 400-25,600)25,600 (6,400-102,400)117 ( 400-400)DHFR(5) 400 400 400 400 Open in a separate windows aIndividual sera from lender voles immunized with the indicated antigens. bIndividual sera from nonimmunized lender voles drawn 3 weeks after experimental contamination with PUUV (strain Kazan). cIndividual sera from lender voles immunized with DHFR control protein. dHomologous GMT are in boldface. The highest GMT for the four groups immunized with rN proteins (409,600, 84,002, 974,198, and 58,813, respectively) were detected against homologous rN protein. The animals in the groups immunized with PUUV rN or infected with wild-type PUUV (strain Kazan) showed the highest degree of cross-reactivity against ANDV rN, while the group with ANDV rN-immunized animals exhibited the highest cross-reactivity, with the same GMT, 144,815, against both PUUV and TOPV rN proteins. Sera from DOBV rN-immunized animals showed the lowest degree of cross-reactivity to heterologous proteins, with GMT ranging between 19,401 and 38,802 (Table ?(Table33). In addition, individual sera from the different immunization groups of animals were titrated against PUUV native N antigen in ELISA. Vipadenant (BIIB-014) The highest GMT, 301,002, was detected in the group immunized with PUUV rN, with titers ranging Vipadenant (BIIB-014) from 102,400 to 409,600, followed by the groups immunized with ANDV rN, TOPV rN, and DOBV rN, with GMT of 144,815 (range, 25,600 to 409,600), 11,593 (range, 1,600 to 409,600), and 2,425 (range, 400 to 25,600), respectively (Fig. ?(Fig.1).1). The GMT in a group of animals infected with PUUV was 29,863 (range, 6,400 to 102,400). Significant differences in mean antibody responses against PUUV native N antigen were seen between the group immunized with PUUV rN and the groups immunized with TOPV (= 0.006) and DOBV rNs (= 0.0002) but not with the group immunized with ANDV rN (= 0.14) when analyzed by the Mann-Whitney U test. In addition, there was a significant difference in mean antibody response between the groups immunized with ANDV and DOBV rNs (= 0.0004) and with ANDV and TOPV rNs (= 0.018) but not between groups immunized with DOBV and TOPV rNs (= 0.08) (Fig. ?(Fig.1).1). Furthermore, there were no significant differences in antibody titers between the Vipadenant (BIIB-014) guarded and unprotected animals in the ANDV and DOBV rN-immunized groups. The geometric mean.