seven days after host immunization , the distribution of donor b cells to lymph node germinal centers ( relative to their distribution to non-germinal center lymph node areas ) was measured by two-color flow cytometry in which ( a ) donor and host b cells were distinguished by their ig kappa chain allotypes , and ( b ) germinal center b cells were distinguished by their lack of labeling with the monoclonal antibody his22 .
C0282491
lymph node germinal centers
C1517532
germinal center b cells