(Responder [R] X nonresponder [NR])F1 mice give indistinguishable primary in vitro plaque-forming cell (PFC) responses to either R or NR parental macrophages (Mphi) pulsed with the Ir-gene controlled antigen L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT). However, such (R X NR)F1 mice, if primed to GAT, retained in vitro responsiveness to GAT-R-Mphi, but no longer responded to GAT-NR-Mphi. Th...

The genetic control of the immune response of inbred strains of mice to certain antigens has been demonstrated to be governed by a set of Ir genes linked to the major histocompatibility complex (H-2) of mice (1,2). Until recently, the control was thought to be governed by single, dominant genes, located within the I region of the H-2 complex. Merryman et al. (3) originally demonstrated that the...

Oilseed rape (Brassica napus) characteristically has high N uptake efficiency and low N utilization efficiency (NUtE, seed yield/shoot N accumulation). Determining the NUtE phenotype of various genotypes in different growth conditions is a way of finding target traits to improve oilseed rape NUtE. The aim of this study was to compare oilseed rape genotypes grown on contrasting N supply rates in...

The in vivo effects of intravenous administration of alloantisera directed to I-J subregion coded determinants were investigated. In confirmation and extension of our previous results, anti-I-Jk [B10.A(3R) anti-B10.A(5R)] and anti-I-Js ([B10.A(3R) X B10.S(9R)]F1 anti-B10.HTT) antisera, when administered in 1 to 10 microliter amounts at the time of immunization, led to twofold increases in the I...

The cellular requirements for immune response (Ir) gene expression in a T cell proliferative response under dual Ir gene control were examined with radiation-induced bone marrow chimeras. The response to poly(Glu55Lys36Phe9)n (GLphi) requires two responder alleles that in the [B10.A X B10.A(18R)]F1 map in I-Ab and I-Ek/Cd. Chimeras in which a mixture of the nonresponder B10.A parental cells (wh...

A monoclonal T cell-derived suppressor factor specific for the terpolymer poly(LGlu'LAla3LTyr'0) produced by the T-cell hybridoma 258 C4.4, was purified to homogeneity. This was accomplished by fractionation of the culture medium by using a combination of affinity chromatography and reversephase and ion-exchange high-performance liquid chromatography. The purified factor is composed of a single...

See related article, pages 993–997. Sixteen years after the results of The National Institute of Neurological Disorders and Stroke rtPA Stroke Study, intravenous alteplase (IV tissue plasminogen activator [tPA]) is still the unique recommended therapy for patients with acute ischemic stroke.1 Since 1995, no other acute stroke therapy has replaced this gold standard, but is IV tPA really a silve...